Artículos de revistas: "Imarad Imaging Systems LTD"

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Mitchell, Gregory S., Ruby K. Gill, David L. Boucher, Changqing Li y Simon R. Cherry. "In vivo Cerenkov luminescence imaging: a new tool for molecular imaging". Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences 369, n.º 1955 (28 de noviembre de 2011): 4605–19. http://dx.doi.org/10.1098/rsta.2011.0271.

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Cerenkov radiation is a phenomenon where optical photons are emitted when a charged particle moves faster than the speed of light for the medium in which it travels. Recently, we and others have discovered that measurable visible light due to the Cerenkov effect is produced in vivo following the administration of β-emitting radionuclides to small animals. Furthermore, the amounts of injected activity required to produce a detectable signal are consistent with small-animal molecular imaging applications. This surprising observation has led to the development of a new hybrid molecular imaging modality known as Cerenkov luminescence imaging (CLI), which allows the spatial distribution of biomolecules labelled with β-emitting radionuclides to be imaged in vivo using sensitive charge-coupled device cameras. We review the physics of Cerenkov radiation as it relates to molecular imaging, present simulation results for light intensity and spatial distribution, and show an example of CLI in a mouse cancer model. CLI allows many common radiotracers to be imaged in widely available in vivo optical imaging systems, and, more importantly, provides a pathway for directly imaging β − -emitting radionuclides that are being developed for therapeutic applications in cancer and that are not readily imaged by existing methods.

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Connolly, Christine. "High‐speed imaging investigations from Pixoft Diagnostic Imaging Ltd". Assembly Automation 26, n.º 3 (julio de 2006): 184–87. http://dx.doi.org/10.1108/01445150610679696.

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Dorney, Timothy D., William W. Symes y Daniel M. Mittleman. "Multistatic Reflection Imaging with Terahertz Pulses". International Journal of High Speed Electronics and Systems 13, n.º 02 (junio de 2003): 677–99. http://dx.doi.org/10.1142/s0129156403001855.

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Recent advances in the technique of terahertz time-domain spectroscopy have led to the development of the first fiber-coupled room-temperature broadband terahertz sources and detectors. The fiber coupling permits the repositioning of the emitter and receiver antennas without loss of temporal calibration or alignment, thus enabling multistatic imaging. We describe a new imaging method which exploits this new capability. This technique emulates the data collection and image processing procedures developed for geophysical prospecting. We use a migration procedure to solve the inverse problem; this permits us to reconstruct the location, shape, and refractive index of targets. We show examples for both metallic and dielectric model targets, and we perform velocity analysis on dielectric targets to estimate the refractive indices of imaged components. These results broaden the capabilities of terahertz imaging systems, and also demonstrate the viability of the THz system as a test bed for the exploration of new seismic processing methods.

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Gilley, Patrik, Ke Zhang, Neman Abdoli, Youkabed Sadri, Laura Adhikari, Kar-Ming Fung y Yuchen Qiu. "Development and Assessment of Multiple Illumination Color Fourier Ptychographic Microscopy for High Throughput Sample Digitization". Sensors 24, n.º 14 (12 de julio de 2024): 4505. http://dx.doi.org/10.3390/s24144505.

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In this study, we proposed a multiplexed color illumination strategy to improve the data acquisition efficiency of Fourier ptychography microscopy (FPM). Instead of sequentially lighting up one single channel LED, our method turns on multiple white light LEDs for each image acquisition via a color camera. Thus, each raw image contains multiplexed spectral information. An FPM prototype was developed, which was equipped with a 4×/0.13 NA objective lens to achieve a spatial resolution equivalent to that of a 20×/0.4 NA objective lens. Both two- and four-LED illumination patterns were designed and applied during the experiments. A USAF 1951 resolution target was first imaged under these illumination conditions, based on which MTF curves were generated to assess the corresponding imaging performance. Next, H&E tissue samples and analyzable metaphase chromosome cells were used to evaluate the clinical utility of our strategy. The results show that the single and multiplexed (two- or four-LED) illumination results achieved comparable imaging performance on all the three channels of the MTF curves. Meanwhile, the reconstructed tissue or cell images successfully retain the definition of cell nuclei and cytoplasm and can better preserve the cell edges as compared to the results from the conventional microscopes. This study initially validates the feasibility of multiplexed color illumination for the future development of high-throughput FPM scanning systems.

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Foroni, R., G. Gambraini, U. Danesi, M. Mauri, E. Pompilio, L. Pirola, A. Nicolato, P. Ferraresi y M. Gerosa. "New dosimetric approach for multidimensional dose evaluation in gamma knife radiosurgery". Journal of Neurosurgery 93, supplement_3 (diciembre de 2000): 239–42. http://dx.doi.org/10.3171/jns.2000.93.supplement_3.0239.

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✓ During the past two decades, the progress in computerized treatment planning systems has led to more accurate imaging and therapy by using the gamma knife, especially with the smallest collimators (4 mm). However, the ionization chambers that have been used to calibrate the gamma knife are not useful with the smallest collimators because the chambers are too big compared with the irradiated volume. Therefore, it is important to develop more suitable dosimeters. This study proposes a new dosimeter method. The FriXyGel method proposed here is based on a phantom dosimeter, an acquisition chain, and dedicated software. This dosimeter uses an agarose gel into which a ferrous sulphate solution (Fricke solution) and a metal ion indicator (xylenol orange) are incorporated. The absorbed dose is detected through measurements of visible light transmission, imaged by means of a charge-coupled device camera provided with a suitable optical filter. Gel layers are imaged before and after irradiation, and the differences in light absorption are related to the absorbed dose. By choosing convenient thickness of gel layers and by building up a phantom with different gel slices, it is possible to obtain a three-dimensional (3D) representation of the absorbed dose. The final 3D representation is reached after several mathematical processes have been applied to the images. The first step identifies and reduces all factors that could alter the original data, such as nonuniformity in illumination. Then, after calibration procedures, it is possible to obtain absorbed dose values and to discover their 3D representation. This goal has been reached by developing appropriate software that performs all the calculations necessary for spatial representation routines and prompt comparison with theoretical calculations.

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Akter, Shirin, Rajada Khatun, S. M. Enamul Kabir, Ashrafun Nahar Monika, Md Fakhar Uddin, Md Mahfuzur Rahman y Mohammad Monjur Ahasan. "Dosimetric Verification of Computed Tomography (CT) Systems Using CTDI Phantom". Bangladesh Journal of Nuclear Medicine 26, n.º 2 (23 de junio de 2024): 172–76. http://dx.doi.org/10.3329/bjnm.v26i2.71488.

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Background: Computed tomography (CT) is a medical imaging modality that contributes widely over the world for the diagnosis of disease and for treatment planning in the radiotherapy department. The purpose of the study is to measure the accuracy of dose of CT System for quality treatment. Materials and Methods: The study was executed in a 16 slice SOMATOM Emotion CT Scanner of Delta Hospital Ltd. with Tube voltage 130 KV and Tube current 25 mA using Computed Tomography Dose Index (CTDI) phantom (CIRS) of MPD, Atomic Energy Centre, Dhaka. IBA pencil ionization chamber was used to measure the dose at different positions inside the CTDI phantom and data were collected using IBA MagicMax Universal software. The CT radiation doses were estimated using formalisms in the AAPM Report 96 and 111. Results: For the Adult Body Phantom Console displayed dose was 16.03 mGy and estimated dose was found as16.40 mGy. For the Adult Head Phantom, console displayed dose was 32.40 mGy and estimated dose was found as 34.60 mGy. Between the estimated and console displayed doses for Adult Body Phantom and Adult Head Phantom a deviation was realized of 2.3% and 6.8% respectively. Conclusion: Hence CTDI of the above mentioned machine comply with reference value within a tolerance of ± 20 % according to Food and Drug Administration (FDA). Bangladesh J. Nuclear Med. 26(2): 172-176, 2023

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Grothusen, John R. "Laser Doppler Imaging: Usefulness in Chronic Pain Medicine". Pain Physician 5;14, n.º 5;9 (14 de septiembre de 2011): 491–98. http://dx.doi.org/10.36076/ppj.2011/14/491.

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Sympathetic nervous system dysfunction is thought to be a factor in neuropathic pain conditions such as Complex Regional Pain Syndrome and in vascular conditions such as Raynaud’s phenomenon. Laser Doppler fluxmetry has been used as a fast non-invasive method to quantify changes in skin capillary blood flow which reflect activation of sympathetically mediated vasoconstriction of the arterioles that supply the capillaries. Studies of dynamic change of skin capillary blood flow with sympathetic activation such as cold or inspiratory gasp have generally used single point laser Doppler systems where the probe is in contact with the skin. The results are a single line tracing representing the capillary flow at a single point on the skin a few millimeters in diameter. Laser Doppler imaging (moorLDI laser Doppler imager, Moor Instruments Ltd.) allows for non-contact recording of skin blood flow of an area as large as 50 centimeters square with a resolution of 256 by 256 pixels and 4 milliseconds per pixel. Most work with laser Doppler imaging has studied changes that occur between successive scans. We have found it useful to look at changes that occur during a scan. In this way we obtain data that is comparable to the time resolution of single point laser Doppler methods, but with the larger spatial information that is available with laser Doppler imaging. We present a small series of case reports in which inspiratory gasp during laser Doppler imaging was able to provide quick, useful and unequivocal clinical information regarding the status of regional bilateral skin capillary response to sympathetic activation. This may be useful for distinguishing sympathetically mediated from sympathetically independent pain. We believe the methods described may provide the basis for future quantitative studies similar to those that use single point laser Doppler methods. Key words: Laser doppler, laser Doppler imaging, sympathetically maintained pain, Raynaud’s phenomen, complex regional pain syndrome

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Pransky, Joanne. "Dr Amit Goffer, co-founder at UPnRIDE, serial inventor and entrepreneur". Industrial Robot: An International Journal 45, n.º 2 (19 de marzo de 2018): 175–80. http://dx.doi.org/10.1108/ir-01-2018-0009.

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Purpose The following article is a “Q&A interview” conducted by Joanne Pransky of Industrial Robot Journal as a method to impart the combined technological, business and personal experience of a prominent industry engineer-turned successful innovator and entrepreneur regarding the development of his inventions and the challenges he faced. This paper aims to discuss these issues. Design/methodology/approach The interviewee is Dr Amit Goffer, Chief Technology Officer and President at UPnRIDE Robotics Ltd., a startup that makes a wheeled robotic device for almost anyone who is unable to physically stand or walk. He served as Chief Executive Officer (until 2012) and President and Chief Technical Officer of ReWalk Robotics, a company he founded in 2001 (previously called Argo Medical Technologies Ltd). Prior to Argo/ReWalk, Dr Goffer served as the Founder at Odin Medical Technologies Ltd. (later acquired by Medtronic), President and Chief Executive Officer. As an accomplished inventor and serial entrepreneur of medical devices, Goffer describes how his education in school and in running his companies combined with his life experiences led to his breakthroughs. Findings Dr Amit Goffer completed BSc from Technion-Israel Institute of Technology, MSc from Tel-Aviv University, Israel, and PhD from Drexel University, Philadelphia, USA, all in electrical and computer engineering. After working for Elscint, a medical imaging company, Goffer started Odin Medical to provide real-time magnetic resonance imaging images for brain surgery. After a tragic accident confined him to a wheelchair, Goffer created ReWalk, a robotic exoskeleton that enables people with lower limb disabilities to stand, walk, ascend/descend stairs and more. He recently founded his latest company, UPnRIDE. Originality/value Dr Amit Goffer is highly regarded as a pioneer of the emerging exoskeleton industry. His invention and development of the ReWalk Robotics wearable exoskeleton has enabled so far hundreds of wheelchair users to walk again, and another estimated 500,000 could benefit from it. Despite Goffer not being able to use the ReWalk himself, as he is a quadriplegic, his greatest passion is to improve the disabled’s self-esteem and quality of life. ReWalk was the first commercially available exoskeleton in the USA. It was named “best invention” by Popular Science and Time magazines. ReWalk Robotics went public in 2014. In 2015, the US Veteran’s Administration announced they would provide ReWalks for all eligible veterans with spinal cord injuries. Goffer recently devised UPnRIDE as a new product, allowing millions of wheelchair users worldwide, including himself, full mobility in the standing position in almost any urban environment.

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Askari, Mohammad Sadegh, Sharon M. O'Rourke y Nicholas M. Holden. "A comparison of point and imaging visible-near infrared spectroscopy for determining soil organic carbon". Journal of Near Infrared Spectroscopy 26, n.º 2 (abril de 2018): 133–46. http://dx.doi.org/10.1177/0967033518766668.

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This study evaluated whether the accuracy of soil organic carbon measurement by laboratory hyperspectral imaging can match that of standard point spectroscopy operating in the visible–near infrared. Hyperspectral imaging allows a greater amount of spectral information to be collected from the soil sample compared to standard spectroscopy, accounting for greater sample representation. A total of 375 representative Irish soils were scanned by two-point spectrometers (a Foss NIR Systems 6500 labelled S-1 and a Varian FT-IR 3100 labelled S-2) and two laboratory hyperspectral imaging systems (two push broom line-scanning hyperspectral imaging systems manufactured by DV optics and Spectral Imaging Ltd, respectively, labelled S-3 and S-4). The objectives were (a) to compare the predictive ability of spectral datasets for soil organic carbon prediction for each instrument evaluated and (b) to assess the impact of imposing a common wavelength range and spectral resolution on soil organic carbon model accuracy. These objectives examined the predictive ability of spectral datasets for soil organic carbon prediction based on optimal settings of each instrument in (a) and introduced a constraint in wavelength range and spectral resolution to achieve common settings for instruments in (b). Based on optimal settings for each instrument, the deviation (root-mean square error of prediction) from the best fit line between laboratory measured and predicted soil organic carbon, ranked the instruments as S-1 (26.3 g kg−1) < S-2 (29.4 g kg−1) < S-3 (34.3 g kg−1) < S-4 (41.1 g kg−1). The S-1 model outperformed in all partial least squares regression performance indicators, and across all spectral ranges, and produced the most favourable outcomes in means testing, variance testing and identification of significant variables. It is assumed that a larger wavelength range produced more accurate soil organic carbon predictions for S-1 and S-2. Under common instrument settings, the prediction accuracy for S-3 that was almost equal to S-1. It is concluded that under standard operating procedures, greater soil sample representation captured by hyperspectral imaging can equal the quality of the spectra from point spectroscopy. This result is important for the development of laboratory hyperspectral imaging for soil image analysis.

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Chiabrando, F. y L. Teppati Losè. "PERFORMANCE EVALUATION OF COTS UAV FOR ARCHITECTURAL HERITAGE DOCUMENTATION. A TEST ON S.GIULIANO CHAPEL IN SAVIGLIANO (CN) – ITALY". ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences XLII-2/W6 (23 de agosto de 2017): 77–84. http://dx.doi.org/10.5194/isprs-archives-xlii-2-w6-77-2017.

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Even more the use of UAV platforms is a standard for images or videos acquisitions from an aerial point of view. According to the enormous growth of requests, we are assisting to an increasing of the production of COTS (Commercial off the Shelf) platforms and systems to answer to the market requirements. In this last years, different platforms have been developed and sell at low-medium cost and nowadays the offer of interesting systems is very large. One of the most important company that produce UAV and other imaging systems is the DJI (Dà-Jiāng Innovations Science and Technology Co., Ltd) founded in 2006 headquartered in Shenzhen – China. The platforms realized by the company range from low cost systems up to professional equipment, tailored for high resolution acquisitions useful for film maker purposes. According to the characteristics of the last developed low cost DJI platforms, the onboard sensors and the performance of the modern photogrammetric software based on Structure from Motion (SfM) algorithms, those systems are nowadays employed for performing 3D surveys starting from the small up to the large scale. The present paper is aimed to test the characteristic in terms of image quality, flight operations, flight planning and accuracy evaluation of the final products of three COTS platforms realized by DJI: the Mavic Pro, the Phantom 4 and the Phantom 4 PRO. The test site chosen was the Chapel of San Giuliano in the municipality of Savigliano (Cuneo-Italy), a small church with two aisles dating back to the early eleventh century.

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Hanuš, J., T. Fabiánek y L. Fajmon. "POTENTIAL OF AIRBORNE IMAGING SPECTROSCOPY AT CZECHGLOBE". ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences XLI-B1 (2 de junio de 2016): 15–17. http://dx.doi.org/10.5194/isprsarchives-xli-b1-15-2016.

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Ecosystems, their services, structures and functions are affected by complex environmental processes, which are both natural and human-induced and globally changing. In order to understand how ecosystems behave in globally changing environment, it is important to monitor the current status of ecosystems and their structural and functional changes in time and space. An essential tool allowing monitoring of ecosystems is remote sensing (RS). Many ecosystems variables are being translated into a spectral response recorded by RS instruments. It is however important to understand the complexity and synergies of the key ecosystem variables influencing the reflected signal. This can be achieved by analysing high resolution RS data from multiple sources acquired simultaneously from the same platform. Such a system has been recently built at CzechGlobe - Global Change Research Institute (The Czech Academy of Sciences). CzechGlobe has been significantly extending its research infrastructure in the last years, which allows advanced monitoring of ecosystem changes at hierarchical levels spanning from molecules to entire ecosystems. One of the CzechGlobe components is a laboratory of imaging spectroscopy. The laboratory is now operating a new platform for advanced remote sensing observations called FLIS (Flying Laboratory of Imaging Spectroscopy). FLIS consists of an airborne carrier equipped with passive RS systems. The core instrument of FLIS is a hyperspectral imaging system provided by Itres Ltd. The hyperspectral system consists of three spectroradiometers (CASI 1500, SASI 600 and TASI 600) that cover the reflective spectral range from 380 to 2450 nm, as well as the thermal range from 8 to 11.5 μm. The airborne platform is prepared for mounting of full-waveform laser scanner Riegl-Q780 as well, however a laser scanner is not a permanent part of FLIS. In 2014 the installation of the hyperspectral scanners was completed and the first flights were carried out with all sensors. The new hyperspectral imaging system required adaptations in the data pre-processing chain. The established pre-processing chain (radiometric, atmospheric and geometric corrections), which was tailored mainly to the AISA Eagle instrument operated at CzechGlobe since 2004, has been now modified to fit the new system and users needs. Continuous development of the processing chain is now focused mainly on establishing pre-processing of thermal data including emissivity estimation and also on joint processing of hyperspectral and laser scanning data.

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Hanuš, J., T. Fabiánek y L. Fajmon. "POTENTIAL OF AIRBORNE IMAGING SPECTROSCOPY AT CZECHGLOBE". ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences XLI-B1 (2 de junio de 2016): 15–17. http://dx.doi.org/10.5194/isprs-archives-xli-b1-15-2016.

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Ecosystems, their services, structures and functions are affected by complex environmental processes, which are both natural and human-induced and globally changing. In order to understand how ecosystems behave in globally changing environment, it is important to monitor the current status of ecosystems and their structural and functional changes in time and space. An essential tool allowing monitoring of ecosystems is remote sensing (RS). Many ecosystems variables are being translated into a spectral response recorded by RS instruments. It is however important to understand the complexity and synergies of the key ecosystem variables influencing the reflected signal. This can be achieved by analysing high resolution RS data from multiple sources acquired simultaneously from the same platform. Such a system has been recently built at CzechGlobe - Global Change Research Institute (The Czech Academy of Sciences). CzechGlobe has been significantly extending its research infrastructure in the last years, which allows advanced monitoring of ecosystem changes at hierarchical levels spanning from molecules to entire ecosystems. One of the CzechGlobe components is a laboratory of imaging spectroscopy. The laboratory is now operating a new platform for advanced remote sensing observations called FLIS (Flying Laboratory of Imaging Spectroscopy). FLIS consists of an airborne carrier equipped with passive RS systems. The core instrument of FLIS is a hyperspectral imaging system provided by Itres Ltd. The hyperspectral system consists of three spectroradiometers (CASI 1500, SASI 600 and TASI 600) that cover the reflective spectral range from 380 to 2450 nm, as well as the thermal range from 8 to 11.5 μm. The airborne platform is prepared for mounting of full-waveform laser scanner Riegl-Q780 as well, however a laser scanner is not a permanent part of FLIS. In 2014 the installation of the hyperspectral scanners was completed and the first flights were carried out with all sensors. The new hyperspectral imaging system required adaptations in the data pre-processing chain. The established pre-processing chain (radiometric, atmospheric and geometric corrections), which was tailored mainly to the AISA Eagle instrument operated at CzechGlobe since 2004, has been now modified to fit the new system and users needs. Continuous development of the processing chain is now focused mainly on establishing pre-processing of thermal data including emissivity estimation and also on joint processing of hyperspectral and laser scanning data.

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Cornu, B., C. Roure, D. Moulin, N. Estre, D. Tisseur, M.-P. Ferroud-Plattet, P. Kinnunen, P. Kotiluoto y A. Revuelta. "Non-Destructive Examination Development for the JHR Material Testing Reactor". EPJ Web of Conferences 225 (2020): 04001. http://dx.doi.org/10.1051/epjconf/202022504001.

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The Jules Horowitz Reactor (JHR) is a European material testing reactor (MTR) under construction at the CEA Cadarache centre. It will be dedicated to material and fuel irradiation tests, as well as to the production of medical isotopes. Gamma and X-Ray benches will be implemented in the reactor pool (RER), the irradiated component storage pool (EPI) and in a shielded hot cell for measuring either the whole underwater test device still containing the experimental sample or just the experimental sample before its extraction in the hot cell. The CEA/Cadarache Nuclear Measurement Laboratory (LMN) has been working in collaboration with VTT (Technical Research Centre in Finland Ltd.) since 2008 under a Finnish in-kind contribution agreement. This agreement focuses on the development of NDE systems implementing gamma-ray spectroscopy and high-energy X-ray imaging of the sample and irradiation device with the highest definition possible (resolution of 100 μm). The CEA-VTT technical specifications led to a European call for tenders launched by VTT. The contract was awarded to the Spanish company IDOM for the design, manufacturing, assembly and commissioning of: - Underwater gamma and X-ray (UGXR) mechanical benches and their associated gamma and X-ray collimation systems for the RER and EPI pools - Hot cell gamma and X-ray (HGXR) bench in the JHR NDE hot cell. The Final Design Reviews (FDR) of the UGXR and HGXR systems were completed in 2016. The design phase has been an iterative process in order to manage interfacing specifications and constraints: - Challenging experimental requirements, mainly to cover the wide diversity of sample shapes, sample activity levels and measurement processes, but also to achieve a level of mechanical accuracy to reach the ambitious geometrical resolution target in X-ray imaging, - Environmental constraints (immersion, radiation, compactness, limited accessibility for maintenance), - Nuclear safety constraints (seism, radiation protection). The whole design process has produced a number of elaborate and innovative mechatronic systems, which is rather unusual in nuclear applications since the resulting solutions have benefited from IDOM’s technological expertise in designing and commissioning large telescopes for the astronomy sector. Once the manufacturing phase and assembly finalised, the site acceptance tests for the UGXR and HGXR mechanical systems will be performed in 2019-2020 in the TOTEM facility at the CEA Cadarache center. The underwater benches will be tested in the CESARINE pool to check their requirements.

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Wada, Kojiro, Hirohiko Arimoto, Hidenori Ohkawa, Toshiki Shirotani, Yohsitaro Matsushita y Takashi Takahara. "Usefulness of Preoperative Three-Dimensional Computed Tomographic Angiography With Two-Dimensional Computed Tomographic Imaging for Rupture Point Detection of Middle Cerebral Artery Aneurysms". Operative Neurosurgery 62, suppl_1 (1 de marzo de 2008): ONS126—ONS133. http://dx.doi.org/10.1227/01.neu.0000317382.45691.1a.

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Abstract Objective: We report the technique of three-dimensional computed tomographic (CT) angiography with a two-dimensional CT image aiding in the early operation of ruptured middle cerebral artery aneurysms. This combined image allows the prediction of the rupture point in the aneurysm and may reduce the risk of rupture during early clipping surgery. Methods: The findings for 14 patients with 14 middle cerebral artery ruptured aneurysms who underwent subsequent early clipping were analyzed. The average aneurysm size was 8.5 mm, and there were two large and one giant aneurysms. CT examinations were performed by means of a multidetector CT scanner (Aquilion M16; Toshiba Medical Systems, Tokyo, Japan) and reconstructed with a workstation (ZIO M900 QUADRA; Amin Co., Ltd., Tokyo, Japan). We constructed an operating view through three-dimensional CT angiography for a lateral transsylvian approach with a two-dimensional CT image (nonshaded volume-rendering image), which was perpendicular to the direction of the surgical approach. Using this combined image, we predicted the rupture point of the aneurysm and successfully performed clipping surgery through a lateral transsylvian approach. Rupture points were confirmed at the time of surgery. Rupture points of 13 out of 14 aneurysms appeared as we expected, but one differed; all aneurysms were successfully clipped. Thirteen of the 14 patients could be clipped without rupture at surgery, but the remaining patient experienced rupture just after craniotomy. Conclusion: The combination of three-dimensional CT angiography and two-dimensional CT images may help improve the surgical outcome by indicating aneurysmal rupture points, leading to the prevention of rupture.

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Takahashi, Miwako, Go Akamatsu, Tomohiro Yamaki, Shinji Onodera y Taiga Yamaya. "RT-4 WORLD'S FIRST HEMISPHERE-SHAPE BRAIN-DEDICATED PET FOR SMALL LESION DETECTION". Neuro-Oncology Advances 4, Supplement_3 (1 de diciembre de 2022): iii13—iii14. http://dx.doi.org/10.1093/noajnl/vdac167.049.

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Abstract Positron emission tomography (PET) is useful to detect malignant tumors by imaging glucose or amino acid metabolism. Whole-body PET with the detector arrangement in a large diameter is currently used for brain imaging, however, the detector arrangement in small diameter is better for brain imaging. Stereotactic radiosurgery (SRS) treats brain tumor with maintaining cognitive function. Therefore, it needs more dedicated PET to identify small lesions and their localization. Then, we developed the world's first brain-dedicated PET with detectors arranged in a hemisphere of 28 cm diameter, attaining 2.2 mm in spatial resolution. This development was performed with ATOX CO., LTD and the brain-dedicated PET has been commercialized as VrainTM. Ten normal volunteers (22 - 45 age male) underwent 18FDG-PET using a whole-body PET (Discovery MI, GE) and the brain-PET for 10-min each, which were started 30-min and 45-min after FDG injection, respectively. A phantom with 10-22 diameter hot spheres and background (radioactivity ratio, 4:1) was also acquired by both PET systems, then estimated the radioactivity ratio in case of 2-mm diameter hot sphere. As a results, the inferior colliculus, substantia nigra, red nucleus, and brain stem raphe nucleus were identified with the brain-PET. The inferior colliculus was identified with the whole-body PET, but other nuclei were not. Based on phantom study, it was estimated that radioactivity in a 2-mm diameter sphere was measured with 1.4 - 2.9 times higher contrast than whole-body PET. The substantia nigra and the red nucleus has 5.0-6.0mm in short diameter on MRI T2WI axial image. The raphe nucleus extends laterally to 2.5mm on postmortem brain specimens. We concluded that our brain-dedicated PET can identify approximately 2.5mm diameter tumor clearly and will be particularly useful in SRS.

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Mitchell, Robert A., Philip Wai, Ruth Colgan, Anna M. Kirby y Ellen M. Donovan. "Improving the efficiency of breast radiotherapy treatment planning using a semi‐automated approach". Journal of Applied Clinical Medical Physics 18, n.º 1 (30 de noviembre de 2016): 18–24. http://dx.doi.org/10.1002/acm2.12006.

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AbstractObjectivesTo reduce treatment planning times while maintaining plan quality through the introduction of semi‐automated planning techniques for breast radiotherapy.MethodsAutomatic critical structure delineation was examined using the Smart Probabilistic Image Contouring Engine (SPICE) commercial autosegmentation software (Philips Radiation Oncology Systems, Fitchburg, WI) for a cohort of ten patients. Semiautomated planning was investigated by employing scripting in the treatment planning system to automate segment creation for breast step‐and‐shoot planning and create objectives for segment weight optimization; considerations were made for three different multileaf collimator (MLC) configurations. Forty patients were retrospectively planned using the script and a planning time comparison performed.ResultsThe SPICE heart and lung outlines agreed closely with clinician‐defined outlines (median Dice Similarity Coefficient > 0.9); median difference in mean heart dose was 0.0 cGy (range −10.8 to 5.4 cGy). Scripted treatment plans demonstrated equivalence with their clinical counterparts. No statistically significant differences were found for target parameters. Minimal ipsilateral lung dose increases were also observed. Statistically significant (P < 0.01) time reductions were achievable for MLCi and Agility MLC (Elekta Ltd, Crawley, UK) plans (median 4.9 and 5.9 min, respectively).ConclusionsThe use of commercial autosegmentation software enables breast plan adjustment based on doses to organs at risk. Semi‐automated techniques for breast radiotherapy planning offer modest reductions in planning times. However, in the context of a typical department's breast radiotherapy workload, minor savings per plan translate into greater efficiencies overall.

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Tufail, Adnan, Venediktos V. Kapetanakis, Sebastian Salas-Vega, Catherine Egan, Caroline Rudisill, Christopher G. Owen, Aaron Lee et al. "An observational study to assess if automated diabetic retinopathy image assessment software can replace one or more steps of manual imaging grading and to determine their cost-effectiveness". Health Technology Assessment 20, n.º 92 (diciembre de 2016): 1–72. http://dx.doi.org/10.3310/hta20920.

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Background Diabetic retinopathy screening in England involves labour-intensive manual grading of retinal images. Automated retinal image analysis systems (ARIASs) may offer an alternative to manual grading. Objectives To determine the screening performance and cost-effectiveness of ARIASs to replace level 1 human graders or pre-screen with ARIASs in the NHS diabetic eye screening programme (DESP). To examine technical issues associated with implementation. Design Observational retrospective measurement comparison study with a real-time evaluation of technical issues and a decision-analytic model to evaluate cost-effectiveness. Setting A NHS DESP. Participants Consecutive diabetic patients who attended a routine annual NHS DESP visit. Interventions Retinal images were manually graded and processed by three ARIASs: iGradingM (version 1.1; originally Medalytix Group Ltd, Manchester, UK, but purchased by Digital Healthcare, Cambridge, UK, at the initiation of the study, purchased in turn by EMIS Health, Leeds, UK, after conclusion of the study), Retmarker (version 0.8.2, Retmarker Ltd, Coimbra, Portugal) and EyeArt (Eyenuk Inc., Woodland Hills, CA, USA). The final manual grade was used as the reference standard. Arbitration on a subset of discrepancies between manual grading and the use of an ARIAS by a reading centre masked to all grading was used to create a reference standard manual grade modified by arbitration. Main outcome measures Screening performance (sensitivity, specificity, false-positive rate and likelihood ratios) and diagnostic accuracy [95% confidence intervals (CIs)] of ARIASs. A secondary analysis explored the influence of camera type and patients’ ethnicity, age and sex on screening performance. Economic analysis estimated the cost per appropriate screening outcome identified. Results A total of 20,258 patients with 102,856 images were entered into the study. The sensitivity point estimates of the ARIASs were as follows: EyeArt 94.7% (95% CI 94.2% to 95.2%) for any retinopathy, 93.8% (95% CI 92.9% to 94.6%) for referable retinopathy and 99.6% (95% CI 97.0% to 99.9%) for proliferative retinopathy; and Retmarker 73.0% (95% CI 72.0% to 74.0%) for any retinopathy, 85.0% (95% CI 83.6% to 86.2%) for referable retinopathy and 97.9% (95% CI 94.9 to 99.1%) for proliferative retinopathy. iGradingM classified all images as either ‘disease’ or ‘ungradable’, limiting further iGradingM analysis. The sensitivity and false-positive rates for EyeArt were not affected by ethnicity, sex or camera type but sensitivity declined marginally with increasing patient age. The screening performance of Retmarker appeared to vary with patient’s age, ethnicity and camera type. Both EyeArt and Retmarker were cost saving relative to manual grading either as a replacement for level 1 human grading or used prior to level 1 human grading, although the latter was less cost-effective. A threshold analysis testing the highest ARIAS cost per patient before which ARIASs became more expensive per appropriate outcome than human grading, when used to replace level 1 grader, was Retmarker £3.82 and EyeArt £2.71 per patient. Limitations The non-randomised study design limited the health economic analysis but the same retinal images were processed by all ARIASs in this measurement comparison study. Conclusions Retmarker and EyeArt achieved acceptable sensitivity for referable retinopathy and false-positive rates (compared with human graders as reference standard) and appear to be cost-effective alternatives to a purely manual grading approach. Future work is required to develop technical specifications to optimise deployment and address potential governance issues. Funding The National Institute for Health Research (NIHR) Health Technology Assessment programme, a Fight for Sight Grant (Hirsch grant award) and the Department of Health’s NIHR Biomedical Research Centre for Ophthalmology at Moorfields Eye Hospital and the University College London Institute of Ophthalmology.

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Elsharkawy, Sonia L., Wafaa E. AbdEl-Aal, Reham S. E. Esmal, Hanan H. M. Ali, Soheir M. Mahfouz y Ahmed El-Habashi. "Preoperative Evaluation of Thyroid Epithelial Lesions by DNA Ploidy and Galectin-3 Expression in FNAC". Open Access Macedonian Journal of Medical Sciences 2, n.º 4 (15 de diciembre de 2014): 585–94. http://dx.doi.org/10.3889/oamjms.2014.105.

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AIM: This study aimed to investigate the value of DNA ploidy and galectins-3 immunostain in the preoperative evaluation of thyroid epithelial lesions.MATERIAL AND METHODS: Sixty patients presenting with thyroid enlargement were included in this study and referred by clinicians for FNA. Routine cytological evaluation was done on PAP stained slides according to the WHO criteria and at least three slides were prepared for routine cytological examinations. The nuclear DNA analysis was performed at the Pathology Department, National Research Center using the Leica Qwin 500 Image Analyzer (LEICA Imaging Systems Ltd, Cambridge, England). Galectin-3 expression was investigated in all tissues using streptavidin-biotin technique.RESULTS: Conventional Fine needle aspiration cytology (FNAC) of 60 cases could diagnose malignancy with a sensitivity of 60%, negative predictive value (NPV) 71.4%, and overall diagnostic accuracy of 80%. The aneuploidy was significantly associated with malignancy, with sensitivity 90.9%, specificity 83.3% and accuracy 88.3%. On using galectin-3 immunocytochemichal stain on cell blocks prepared from FNA the values were improved, sensitivity 93.3% specificity 86.7% and overall accuracy 90% and it was noticed that galectin-3 over expression was significantly associated with malignancy.CONCLUSIONS: From the results of this study we can consider that DNA ploidy and Galectin-3 could refine the FNA results and increase its sensitivity as a screening test from sensitivity(60%) to reach sensitivity (93.3%), thus decreasing the false negative cases. From this study, it is concluded that the application of ancillary techniques as galectin-3 immunocytochemical markers may become a reliable indicator for surgical intervention, DNA ploidy measurements on the other hand may be of value in galectin-3 negative cases to determine the behavior of the lesion in such cases & refine the preoperative assessment by out ruling false negative cases.

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Cysewska-Sobusiak, Anna Romana. "Examples of acquisition and application of biooptical signals". Photonics Letters of Poland 11, n.º 2 (1 de julio de 2019): 25. http://dx.doi.org/10.4302/plp.v11i2.897.

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Scientific activity of Division of Metrology and Optoelectronics with Poznan University of Poland (PUT) includes methods and systems used in modern electronic, optoelectronic, and biomedical metrology. Noninvasive diagnostic methods applied in medical engineering, with special interest in optoelectronic sensor technology and advanced methods of imaging, are considered in the paper. The author who was the Head of the Division presents the short review of some selected former results of studies related to biophotonics. Full Text: PDF ReferencesA. Cysewska-Sobusiak, "Powers and Limitations of Noninvasive Measurements Implemented in Pulse Oximetry", Biocybernetics and Biomedical Engineering 22 (2002). DirectLink J.G. Webster, Design of pulse oximeters (Bristol, IOP Publishing Ltd 1997). CrossRef T. Aoyagi, "Pulse oximetry: its invention, theory, and future", Journal of Anesthesia 17, 4 (2003). CrossRef A.A. Alian and K.H Shelley, "Photoplethysmography", Anesthesiology 28, 4 (2014). CrossRef F.A. Duck, Physical properties of tissue: a comprehensive reference book (San Diego, Academia Press 1990). CrossRef Z. Krawiecki, A. Cysewska-Sobusiak, G. Wiczyński, and A. Odon, "Modeling and measurements of light transmission through human tissues", Bull. Pol. Ac. Tech. 56, 2 (2008). DirectLink A. Cysewska-Sobusiak, "One-dimensional representation of light-tissue interaction for application in noninvasive oximetry", Opt. Eng. 36, 4 (1997). CrossRef D. Prokop, A. Cysewska-Sobusiak, and A. Hulewicz, "Monitoring of the Arterial Blood Waveforms with a Multi-Sensor System", Procedia Eng. 47 (2012). CrossRef A. Cysewska-Sobusiak, P. Skrzywanek, and A. Sowier, "Utilization of Miniprobes in Modern Endoscopic Ultrasonography", IEEE Sensors Journal 6, 5 (2006). CrossRef A. Cysewska-Sobusiak, G. Wiczyński, Z. Krawiecki, and A. Sowier, "Role of optical techniques in combined use of selected methods of medical imaging", Opto-Electron. Rev. 16, 2 (2008). CrossRef A. Cysewska-Sobusiak, M. Bołtrukiewicz, and J. Parzych, "Evaluation of fluorescence images acquired from oligonucleotide libraries", Optica Applicata 38, 2 (2008). DirectLink M. Jukiewicz and A. Cysewska-Sobusiak, "Stimuli design for SSVEP-based brain computer-interface", Intl. Journal of Electronics and Telecommunications 62, 2 (2016). CrossRef G. Wiczyński, "Inaccuracy of Short-Term Light Flicker Pst Indicator Measuring With a Flickermeter", IEEE Trans. on Power Delivery, 27, 2 (2012). CrossRef A. Hulewicz, "A New Approach to Objective Evaluation of Human Visual Acuity", Phot. Lett. Poland 6, 4 (2014). CrossRef A. Zielińska, K. Kiluk, M. Wojtkowski, and K. Komar, "System for psychophysical measurements of two-photon vision", Phot. Lett. Poland 11, 1 (2019). CrossRef

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Hanna, Verina, Jonathan Oakley, Daniel Russakoff y Netan Choudhry. "Effects of subthreshold nanosecond laser therapy in age-related macular degeneration using artificial intelligence (STAR-AI Study)". PLOS ONE 16, n.º 4 (29 de abril de 2021): e0250609. http://dx.doi.org/10.1371/journal.pone.0250609.

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Purpose To investigate changes in retinal thickness, drusen volume, and visual acuity following subthreshold nanosecond laser (SNL) treatment in patients with age-related macular degeneration (ARMD). Design Retrospective chart review. Methods Patients with intermediate ARMD treated with a single session of SNL (2RT®, Ellex R&D Pty Ltd, Adelaide, Australia) were included. Swept-source optical coherence tomography (OCT) imaging (Triton; Topcon Medical Systems, Tokyo, Japan) was performed within 6 months before and after SNL treatment. Retinal layers were segmented using the artificial intelligence-enabled Orion® software (Voxeleron LLC, San Francisco, USA). The macular region was analyzed according to the Early Treatment Diabetic Retinopathy Study map. Mean difference and standard deviation in baseline and post-treatment retinal layer thicknesses are reported. Results 37 eyes from 25 patients were included in this study (mean age 74.7±9.2 years). An average of 51±6 spots were applied around the macula of each study eye, with a mean spot power of 0.33±0.04mJ. Increases in total retinal thickness were observed within the outer temporal and inferior sectors (P<0.05). Within the annulus, there was an increase in thickness of the sub-retinal pigment epithelial (RPE) space [0.88±2.41μm, P = 0.03], defined between the RPE and Bruch’s membrane. An increase in thickness of 1.13±2.55μm (P = 0.01) was also noted in the inferior sector of the photoreceptor complex, defined from the inner and outer segment junction to the RPE. Decreases in thickness were observed within the superior sector of the inner nuclear layer (INL) [-1.08±2.55μm, P = 0.01], and within the annulus of the outer nuclear layer (ONL) [-1.44±3.55μm, P = 0.02]. Conclusions At 6 months post-SNL treatment, there were sectoral increases in OPL, photoreceptor complex, and sub-RPE space thicknesses and sectoral decreases in INL and ONL thicknesses. This pilot study demonstrates the utility of OCT combined with artificial intelligence-enabled software to track retinal changes that occur following SNL treatment in intermediate ARMD.

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Solodyannikova, O., Y. Kmetyuk, V. Danilenko y G. Sukach. "RADIOISOTOPE DIAGNOSTIC ALGORITHM FOR THE RELAPSE AND METASTASES DETECTION IN THE IODINE-NEGATIVE DIFFERENTIATED THYROID CANCER". Проблеми радіаційної медицини та радіобіології = Problems of Radiation Medicine and Radiobiology 25 (2020): 579–91. http://dx.doi.org/10.33145/2304-8336-2020-25-579-591.

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Objective. Developing of algorithm for the post-surgical management of patients with iodine-negative metastases of differentiated thyroid cancer (DTC). Materials and methods. The DTC patients with iodine-negative metastases (n = 115) were enrolled in the study. Of them the whole body scintigraphy (WBS) was performed with technetium-99m-hexakis-2-methoxyisobutylisonitrile (99mTc-MIBI) (n = 30), WBS with technetium-99m dimercaptosuccinic acid (99mTc-DMSA) (n = 30), 18FDG PET (n = 30), and computer tomography (CT-scan) (n = 25). Complex 99mTc-pertechnetate scans including the dynamic and static scintigraphy was performed supplementary to 99mTc-MIBI WBS in 10 patients to obtain the angiographic curves from DTC metastatic foci. The non-radioiodine radiopharmaceutical technologies, namely the labeled 99mTc-MIBI, 99mTc-DMSA, 99mTc-pertechnetate, and 18FDG were applied to detect the iodine-negative DTC metastases. Radioisotopic examinations were performed at the dual-head gamma camera (Mediso Medical Imaging Systems Ltd., Hungary) and single photonemission computed tomography (SPECT) scanner «E.CAM» (Siemens, Germany). PET/CT scans were performed on the «Biograph 64 TruePoint» imaging platform (Siemens, Germany) in accordance with the European Association of Nuclear Medicine (EANM) recommendations for the Siemens imaging devices with 3D-mode data acquisition. Results. The conducted research suggested that it is feasible to use the non-radioiodine (99mTc-MIBI and 99mTc-DMSA) radiopharmaceutical technologies to detect the iodine-negative DTC metastases. 18FDG PET is a highly informative technology for the detection of iodine-negative DTC metastases in case of lung involvement in the process. Compare of the non-radioiodine radiopharmaceuticals, CT scan and 18FDG-PET/CT indicated the highest sensitivity of 18FDG PET/CT (p < 0.05). WBS with 99mTc-MIBI and 99mTc-DMSA featured the highest specificity (100 %, p < 0.05). X-ray CT is marked by the significantly lower either sensitivity, specificity, and accuracy rate (p > 0.05). Developing and application of algorithm for the post-surgical management of patients with iodine-negative forms of DTC will allow for the betimes detection of relapses and metastases with administration of adequate surgical, radiation, and targeted treatment. Conclusions. Obtained results offer the opportunity to optimize the post-surgical management of patients with iodine-negative DTC forms using the options of radionuclide diagnostics with non-radioiodine radiopharmaceuticals. The latter are readily available providing the cost-cutting of diagnostic support in these patients. Place of morphological methods of diagnosis is determined and stage of monitoring of patients with the iodine-negative metastases is established. Possibility of the 18FDG-PET tests for the early diagnosis of iodine-negative metastases in DTC for the first time have been studied and substantiated in Ukraine. A comprehensive radiation algorithm for the long-term monitoring of this category of patients will allow the timely detection of recurrences and metastases of DTC and appropriate surgery, radiation and targeted therapy administration. Data obtained as a result of the study allowed to improve the overall and recurrence-free survival rates in the able-bodied DTC patients and reduce the costs of follow-up of patients with iodine-negative forms of DTC. Key words: differentiated thyroid cancer, radioiodine-negative metastases, non-radioiodine radiopharmaceuticals, 18FDG-PET/CT.

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VerMilyea, M., J. M. M. Hall, S. M. Diakiw, A. Johnston, T. Nguyen, D. Perugini, A. Miller, A. Picou, A. P. Murphy y M. Perugini. "Development of an artificial intelligence-based assessment model for prediction of embryo viability using static images captured by optical light microscopy during IVF". Human Reproduction 35, n.º 4 (abril de 2020): 770–84. http://dx.doi.org/10.1093/humrep/deaa013.

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Abstract STUDY QUESTION Can an artificial intelligence (AI)-based model predict human embryo viability using images captured by optical light microscopy? SUMMARY ANSWER We have combined computer vision image processing methods and deep learning techniques to create the non-invasive Life Whisperer AI model for robust prediction of embryo viability, as measured by clinical pregnancy outcome, using single static images of Day 5 blastocysts obtained from standard optical light microscope systems. WHAT IS KNOWN ALREADY Embryo selection following IVF is a critical factor in determining the success of ensuing pregnancy. Traditional morphokinetic grading by trained embryologists can be subjective and variable, and other complementary techniques, such as time-lapse imaging, require costly equipment and have not reliably demonstrated predictive ability for the endpoint of clinical pregnancy. AI methods are being investigated as a promising means for improving embryo selection and predicting implantation and pregnancy outcomes. STUDY DESIGN, SIZE, DURATION These studies involved analysis of retrospectively collected data including standard optical light microscope images and clinical outcomes of 8886 embryos from 11 different IVF clinics, across three different countries, between 2011 and 2018. PARTICIPANTS/MATERIALS, SETTING, METHODS The AI-based model was trained using static two-dimensional optical light microscope images with known clinical pregnancy outcome as measured by fetal heartbeat to provide a confidence score for prediction of pregnancy. Predictive accuracy was determined by evaluating sensitivity, specificity and overall weighted accuracy, and was visualized using histograms of the distributions of predictions. Comparison to embryologists’ predictive accuracy was performed using a binary classification approach and a 5-band ranking comparison. MAIN RESULTS AND THE ROLE OF CHANCE The Life Whisperer AI model showed a sensitivity of 70.1% for viable embryos while maintaining a specificity of 60.5% for non-viable embryos across three independent blind test sets from different clinics. The weighted overall accuracy in each blind test set was >63%, with a combined accuracy of 64.3% across both viable and non-viable embryos, demonstrating model robustness and generalizability beyond the result expected from chance. Distributions of predictions showed clear separation of correctly and incorrectly classified embryos. Binary comparison of viable/non-viable embryo classification demonstrated an improvement of 24.7% over embryologists’ accuracy (P = 0.047, n = 2, Student’s t test), and 5-band ranking comparison demonstrated an improvement of 42.0% over embryologists (P = 0.028, n = 2, Student’s t test). LIMITATIONS, REASONS FOR CAUTION The AI model developed here is limited to analysis of Day 5 embryos; therefore, further evaluation or modification of the model is needed to incorporate information from different time points. The endpoint described is clinical pregnancy as measured by fetal heartbeat, and this does not indicate the probability of live birth. The current investigation was performed with retrospectively collected data, and hence it will be of importance to collect data prospectively to assess real-world use of the AI model. WIDER IMPLICATIONS OF THE FINDINGS These studies demonstrated an improved predictive ability for evaluation of embryo viability when compared with embryologists’ traditional morphokinetic grading methods. The superior accuracy of the Life Whisperer AI model could lead to improved pregnancy success rates in IVF when used in a clinical setting. It could also potentially assist in standardization of embryo selection methods across multiple clinical environments, while eliminating the need for complex time-lapse imaging equipment. Finally, the cloud-based software application used to apply the Life Whisperer AI model in clinical practice makes it broadly applicable and globally scalable to IVF clinics worldwide. STUDY FUNDING/COMPETING INTEREST(S) Life Whisperer Diagnostics, Pty Ltd is a wholly owned subsidiary of the parent company, Presagen Pty Ltd. Funding for the study was provided by Presagen with grant funding received from the South Australian Government: Research, Commercialisation and Startup Fund (RCSF). ‘In kind’ support and embryology expertise to guide algorithm development were provided by Ovation Fertility. J.M.M.H., D.P. and M.P. are co-owners of Life Whisperer and Presagen. Presagen has filed a provisional patent for the technology described in this manuscript (52985P pending). A.P.M. owns stock in Life Whisperer, and S.M.D., A.J., T.N. and A.P.M. are employees of Life Whisperer.

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Kubassova, O., M. Boesen, C. Pereira Da Costa, J. O’lynn, A. Patterson y D. Kessler. "POS1127 USE OF ARTIFICIAL INTELLIGENCE AND CLOUD-BASED INFRASTRUCTURE TO IMPROVE THE SPEED AND ACCURACY OF ELIGIBILITY READS IN OSTEOARTHRITIS TRIALS." Annals of the Rheumatic Diseases 81, Suppl 1 (23 de mayo de 2022): 892.2–892. http://dx.doi.org/10.1136/annrheumdis-2022-eular.3815.

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BackgroundThe Kellgren-Lawrence grading (KLG) system is used in clinical trials of osteoarthritis (OA) to define the structural severity of the disease as part of patient eligibility assessment. However, the use of KLG system has proven to be challenging due to considerable inter-reader variability[1], [2], which may result in recruitment of sub-optimal patient cohort or delays in patient recruitment.ObjectivesThe objective of this study was to determine the impact of an AI-assisted, cloud-based data management system on the rate of adjudication and the speed of OA patient recruitment.MethodsA total of 3855 bilateral fixed-flexion posteroanterior radiographs of the tibiofemoral joints from global multi-centre trials were included in this study. Two experienced readers performed an initial KLG assessment of both knees; the adjudication was performed by a third experienced reader. A cloud-based imaging data management system was deployed, the readers could access the data simultaneously and adjudication was automatically triggered.We quantified the adjudication rate and the distribution of disagreements in KLG scores provided by the initial readers. Furthermore, the delay in delivery time of the KLG reports to the recruiting site was recorded.Results48% (1836) of the initial reads required adjudication. Approximately 70% of the disagreements affected the conventional KLG 2-3 inclusion range of OA clinical trials. Use of the cloud-based data management allowed 41% of the reports to be delivered within 24 hours, if no adjudication was required vs an average of 5 days as estimated based on the readers’ prior experience.Table 1 provides details on the distribution of disagreements resulting in adjudication reads. Figure 1 shows the delivery time for KLG with and without adjudication.Table 1.Distribution of disagreements of initial reads resulting in an adjudication read being triggered.Disagreement triggering AdjudicationNumber of CasesPercentageKLG 0 – 171327.8%KLG 1 – 282031.9%KLG 2 – 348218.7%KLG 3 – 444617.4%Other1104.3%Total2569100%Figure 1.Time to deliver eligibility reportNehrer et al. showed that assisting the readers with AI generated KLG scoring reports, the agreement rate between readers for KLG assessment increased by 21% [2]. Adding to this, 30% of the adjudications (stemming from KLG 0 –1 disagreements between readers) could be avoided when using AI generated reports.ConclusionWe assess the rate of adjudication and speed of reporting of KLG of data from multi-centre OA clinical trials. Future work is planned to assess the effect of AI-assisted OA grading systems within our cloud-based data management system on reader agreement and recruitment speed in global clinical trials.References[1]D. J. Hunter et al., “OARSI Clinical Trials Recommendations: Knee imaging in clinical trials inosteoarthritis,” Osteoarthritis and Cartilage, vol. 23, no. 5. W.B. Saunders Ltd, pp. 698–715, 2015. doi: 10.1016/j.joca.2015.03.012.[2]S. Nehrer et al., “Automated Knee Osteoarthritis Assessment Increases Physicians’ Agreement Rate and Accuracy: Data from the Osteoarthritis Initiative,” Cartilage, vol. 13, no. 1_suppl, pp. 957S-965S, Dec. 2021, doi: 10.1177/1947603519888793.Disclosure of InterestsOlga Kubassova Grant/research support from: Takeda, Lilly, Abbvie, Pfizer, Mikael Boesen Speakers bureau: Lilly, Novartis, Abbvie, Pfizer, Cristiano Pereira da Costa: None declared, Julia O’Lynn: None declared, Andrew Patterson: None declared, Dimitri Kessler: None declared

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Mesleh Shayeb, Akram, Richard Barnes, Nicolas Gallastegui Crestani, Cris Hanacek, Peter Aguero, Andres Flores, Rebecca Kruse-Jarres et al. "Validity of Quantitative Measurements By the Joint Tissue Examination and Damage Exam (JADE) with Musculoskeletal Ultrasound for the Longitudinal Assessment of Hemophilic Arthropathy". Blood 136, Supplement 1 (5 de noviembre de 2020): 20–21. http://dx.doi.org/10.1182/blood-2020-143133.

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Introduction: Clinical scoring systems, such as the Hemophilia Joint Health Score (HJHS), and imaging modalities (radiographs and magnetic resonance) are important instruments for the evaluation of hemophilic joint health. However, they are semi-quantitative scales, exhibit ceiling effects, and may not capture subtle dynamic changes of intra-articular structures. We developed the Joint tissue Activity and Damage Exam (JADE) protocol to quantitatively evaluate the extent of hemophilic arthropathy at the tissue level, individualize management, and objectively assess the efficacy of novel therapies. JADE is an economical, convenient, and radiation free point-of-care musculoskeletal ultrasound protocol. JADE uses quantitative numerical measurements (1/10th of millimeter) for osteochondral alterations, cartilage thickness and soft tissue expansion in hemophilic joints and is validated per international OMERACT guidelines for pathological tissue recognition with high intra/inter-rater and inter-operator reliability. Furthermore, we previously reported JADE association with clinical and functional joint assessments at baseline for patients with hemophilia. Herein, we examined JADE protocol ability to capture tissue changes over time and their associations with HJHS, a clinical joint assessment. We assumed the regression lines for joint HJHS on each JADE measurement at each time point would lie parallel to each other. Verifying this assumption would enhance JADE protocol validity and provide confidence that it could be used to monitor hemophilic arthropathy progression by quantifying specific tissue abnormalities. Methodology: We recruited adult patients (≥ 18 years) with congenital hemophilia and arthropathy in a prospective study performed at 3 sites in North America. We assessed joint HJHS and JADE parameters for each patient (n=44; 264 joints [bilateral elbows, ankles, and knees]) at study entry (baseline), at ~12-18 months (midpoint), and ~24-36 months (final). JADE measurements included osteochondral alterations, cartilage thickness, and soft tissue expansion at sentinel positions for each joint. The association between joint HJHS and each JADE variable was examined by fitting random intercept models with outcomes transformed to ensure normal residuals. We examined the assumption of parallel regression lines for the three time points by applying a test for homogeneity of slopes. If no difference between slopes was found, then we applied an analysis of covariance to test whether the lines for each joint were coincident. Results: Joint HJHSs deteriorated measurably during the study period, reflecting clinically worsening arthropathy over time. Importantly, clinical assessment of deterioration for the elbows, knees, and ankles was associated with JADE measurements that changed in the expected direction, namely increased length of osteochondral alterations, decreased cartilage thickness, and increased soft tissue expansion. As an example, figure 1 shows the association of deteriorating HJHS and osteochondral alterations for elbows, knees, and ankles at baseline, midpoint, and final visits. In each graph, the regression lines were similar in shape. Lines were parallel for the elbow (midpoint vs baseline: p = 0.185; final vs baseline: p = 0.398), and the ankle (midpoint vs baseline: p = 0.225; final vs baseline: p = 0.293). But, the assumption of parallel lines was rejected for the knee (midpoint vs baseline: p = 0.047; final vs baseline: p = 0.024). Conclusions: This study demonstrates a tight association between JADE direct ultrasonographic measurements and clinical deterioration (HJHSs) during several assessments over 3 years. Importantly, the associations are consistent across time, despite clinical joint health examinations and ultrasound measurements being performed at three different centers by multiple providers, with long intervals between assessments. Altogether, these findings constitute a major milestone for the clinical relevance validity of the JADE protocol as a precise instrument for tissue-specific alterations measurements over time. These findings support the use of the JADE protocol to monitor the progression of hemophilic arthropathy longitudinally, permit prompt identification of potentially reversible osteochondral and/or soft tissue changes, and study early interventions that could curb arthropathic progression. Disclosures Kruse-Jarres: F. Hoffmann-La Roche Ltd: Speakers Bureau; Biomarin, Chugai Pharmaceutical Co., CSL Behring, CRISPR Therapeutics, Genentech, Inc.: Honoraria; CSL Behring, Genentech, Inc., Spark: Research Funding; Biomarin, Chugai Pharmaceutical Co., CSL Behring, CRISPR Therapeutics, Genentech, Inc.: Consultancy. Steiner:Uniqure: Consultancy, Membership on an entity's Board of Directors or advisory committees; Sanofi/Genzyme: Consultancy, Membership on an entity's Board of Directors or advisory committees; Genentech: Consultancy, Membership on an entity's Board of Directors or advisory committees; Roche: Consultancy, Membership on an entity's Board of Directors or advisory committees. Quon:Bayer: Honoraria; Orthopaedic Institute for Children: Current Employment; Biomarin: Honoraria, Speakers Bureau; Novo Nordisk: Honoraria, Speakers Bureau; Bioverativ/Sanofi: Honoraria, Speakers Bureau; Genentech, Inc./F. Hoffmann-La Roche Ltd: Honoraria, Speakers Bureau; Octapharma: Honoraria; Shire/Takeda: Speakers Bureau. von Drygalski:Biomarin: Honoraria; Hematherix LLC: Membership on an entity's Board of Directors or advisory committees, Other: co-founder; Uniqure: Honoraria; Bioverativ/Sanofi: Honoraria, Research Funding; Pfizer: Research Funding; Novo-Nordisk: Honoraria; Takeda: Honoraria.

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Perifanis, Vassilios, Antonia Kondou, Aikaterini Teli, Efthimia Vlachaki, Marina Economou, Giannoula Tsatra, George P. Spanos y Miranda Athanassiou-Metaxa. "Absence of Relationship of Myocardial T2* to Right Ventricular Function In Thalassaemia Major". Blood 116, n.º 21 (19 de noviembre de 2010): 5160. http://dx.doi.org/10.1182/blood.v116.21.5160.5160.

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Abstract Abstract 5160 Iron-induced cardiac dysfunction is a leading cause of death in transfusion-dependent anemia. Myocardial T2* magnetic resonance imaging (MRI) provides a rapid and reproducible measure of cardiac iron loading and is being increasingly used worldwide for monitoring of transfusion-dependent thalassaemia patients. Recent reports associate myocardial siderosis (T2* <20 ms) with impaired left ventricular (LV) function, as well as with right ventricular (RV) function. As RV dysfunction may play a significant role in heart failure associated with myocardial siderosis the aim of this study was to investigate the relationship between cardiac T2* and RV function in patients treated in a single institution. Methods: A retrospective analysis of 190 well chelated patients with beta-thalassaemia major presenting for their first T2*. MRI scan (examination year 2005) was performed (53.7% male, mean age 26,2±8,3 years). The majority of patients were on Desferrioxamine and 30% were on Deferiprone. Patient's mean ferritin, mean T2* and mean RVEF was 1467±1087 ng/ml, 32,5±15,8ms and 67,9±5,25% respectively. Magnetic resonance images were acquired using a single imager (Philips®, Philips Medical Systems Ltd, Eindhoven, The Netherlands) equipped with a 1.5 Tesla magnet. Each scan included the measurement of heart T2* (mid-septum) together with LV and RV volumes, EF, and mass using previously published techniques. Pearson correlation was used to assess the statistical significance between myocardial T2*, ferritin, RV volumes (End Systolic and End Diastolic), and EF. Results: In 156 patients (Group A) with normal myocardial T2* (>20 ms), the RV ejection fraction (EF) was within the normal range (>55%) in all of them. Mean ferritin, mean T2* and mean RVEF for Group A was 1397±1007ng/ml, 39±11ms and 68,6 ±4,8% respectively. No correlation with feritin was found. In the remaining 34 patients (Group B) with myocardial T2* <20ms, mean ferritin, mean T2* and mean RVEF was 1664±1341ng/ml, 10,8±4,2ms and 64,8±7,35% respectively. Although there was a good correlation between T2* and RVEF for the entire group (A+B) (r=0,312, p=0,001) we did not find a correlation between T2* and RVEF for Group B (r=0,074, p=ns). In the contrary there was a strong correlation between T2* and ferritin for Group B (r=0,382, p=0,0034). There was no other significant correlation between T2* and RESV, REDV for both groups. There was a linear relationship between RV and LVEF for the whole group (r=0,454, p=0,001), for Group A (r=0,269, p=0,015) and more significant for Group B (r=0,720, p=0,001). Conclusions: Myocardial iron deposition by MRI seems not to be associated with RV dysfunction, although it is related to ferritin. The decrease in LV function seen with worsening cardiac iron loading does not necessarily predicts right ventricular dysfunction. The only limitation of our study is that in contrast with other reports the percentage of patients with abnormal T2* was smaller (18%). Larger studies are required to determine the relation of right ventricular function and cardiac iron overload. Disclosures: No relevant conflicts of interest to declare.

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26

Clay, E. Leila Jerome, Miranda Bailey, Dan Drozd, Jincy Paulose, Nicholas Ramscar, Kieran Mace y David Wormser. "A Patient-Centric Approach to Improve the Understanding of Sickle Cell Disease Using Real-World Data". Blood 136, Supplement 1 (5 de noviembre de 2020): 27–28. http://dx.doi.org/10.1182/blood-2020-139148.

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Background: Sickle cell disease (SCD) comprises a group of inherited blood disorders, and is a complex, multi-system, disease. SCD is associated with a variety of clinical complications that affect multiple organ systems. These complications are driven primarily by vaso-occlusion and hemolytic anemia, and can result in end-organ damage and early death. Painful vaso-occlusive crises (VOCs) are a characteristic feature of SCD and can require healthcare intervention. Despite recent advances in the screening, management and treatment of SCD, gaps remain in our understanding of the disease in the real-world setting. These include how best to transition from pediatric to adult care and how to manage specific complications. Currently, most real-world evidence (RWE) is generated from information captured in payer databases, which is not as comprehensive as the information recorded in electronic medical records (EMRs). Despite being potentially valuable sources of real-world, clinical information, EMRs for individual patients in the USA are not centralized, often being held by multiple healthcare providers using different EMRs. This fragmented system prevents generation of clear, comprehensive RWE, both in general and for SCD specifically. Furthermore, there is a lack of harmonization between EMR companies/systems in the types of information included and how it's recorded. A separate approach that collates all available data from EMRs into a single, comprehensive record prior to RWE analysis would therefore greatly improve the accessibility of the available information and the quality of subsequent data analysis. Aims: In contrast to existing RWE, this study explores the value of collating EMRs for each patient into a single, consistently structured format, with the aim of developing richer RWE to complement existing data on SCD. It is hypothesized that the resulting longitudinal overview of each patient's care will contribute to an improved understanding of SCD in the real-world setting: firstly, by better capturing how many VOCs patients with SCD experience, with an indication of the proportion of VOCs that are being home-managed; secondly, by gaining deeper insights into the prevalence and progression of end-organ damage and any association with VOCs; and finally, by highlighting the type and site of care of SCD in the real world (eg medications, treating healthcare professional [HCP] specialties and the type of clinic visited). Study design: The study population will comprise 400 patients with SCD from the USA. Patient recruitment occurs directly via social media and indirectly through a variety of partnerships including HCPs and patient advocacy groups. To enroll, patients sign an informed consent form allowing their de-identified medical information to be shared with third-party organizations to advance SCD research. Enrolled patients gain access to their medical records via a dashboard. The key inclusion criteria are: a confirmed SCD diagnosis (irrespective of phenotype); aged ≥16 years at enrollment; and ≥1 inpatient admission for a VOC in the 12 months prior to enrollment. The key exclusion criterion is the absence of medical records. Components of EMRs collected include doctors' notes, laboratory and test results, clinical imaging and treatment records. Human-curated natural language processing and machine learning is used to extract, structure and code data from the structured sections and unstructured narrative text of the EMR. All medical records, from all visits, will be collected where possible and are expected to comprise ≥7 years of retrospective data for each patient. Results: Between 1 December 2019 and 24 June 2020, a total of 46 patients with a mean age of 36 years (SD 9.7) were enrolled. For each patient, a median of 6.8 years of data from a median of 32.5 providers were obtained. Conclusions: The evidence derived from this study aims to advance the understanding of real-world practices in the management of SCD. It may also provide further learnings regarding the prevalence of complications and any association between VOCs and end-organ damage. Generating a single, structured overview of all EMRs for each patient allows for richer insight generation and a more comprehensive analysis of RWE, compared with existing approaches. The insights gained from this RWE may inform future studies and clinical trials in SCD, with the ultimate aim of improving the quality of life of patients. Disclosures Clay: Novartis: Consultancy; GBT: Consultancy. Bailey:Novartis Pharmaceuticals Corporation: Current Employment. Drozd:F. Hoffmann-La Roche Ltd: Other: All authors received support for third party writing assistance, furnished by Scott Battle, PhD, provided by F. Hoffmann-La Roche, Basel, Switzerland.; PicnicHealth: Current Employment, Current equity holder in private company. Paulose:Novartis Pharma AG: Current Employment. Ramscar:Novartis Pharma AG: Current Employment. Mace:Roche/Genentech: Ended employment in the past 24 months; PicnicHealth: Current Employment. Wormser:Novartis Pharma AG: Current Employment, Current equity holder in publicly-traded company.

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27

Liegel, Jessica J., Poorva Bindal, Richard M. Stone, Robert J. Soiffer, Dina Stroopinsky, Giulia Cheloni, Lina Bisharat et al. "Post-Transplant Vaccination with a Personalized Dendritic Cell/AML Fusion Cell Vaccine for Prevention of Relapse". Blood 138, Supplement 1 (5 de noviembre de 2021): 2830. http://dx.doi.org/10.1182/blood-2021-154166.

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Abstract Allogeneic transplantation is uniquely curative for a subset of patients with acute myeloid leukemia (AML) however, post-transplant relapse and graft versus host disease remain significant concerns. We have developed a vaccine in which patient-derived AML cells are fused with donor-derived dendritic cells (DCs), thereby presenting a broad array of antigens. Previous work (Rosenblatt Sci Transl Med) has suggested that such vaccines given in the first complete remission setting after chemotherapy consolidation elicit specific immune responses and can possibly lessen the risk of relapse. We hypothesize that donor-derived DC/AML vaccination post-transplant would elicit the durable expansion of leukemia- specific T cells within the donor T cell repertoire to effectively protect against disease relapse. We report the results of a phase 1 clinical trial (NCT03679650) evaluating the use of DC/AML fusion vaccine in patients with acute myeloid leukemia (AML) following allogeneic transplant. DC/AML fusion vaccine is generated with autologous leukemia blasts, cryopreserved at the time of diagnosis with AML, and donor-derived dendritic cells. DCs are collected via leukapheresis in pts in CR 25-70 days after an allogenic matched related or unrelated donor transplant (cohort A) or a haplo-identical donor (Cohort B). In order to proceed with leukapheresis, patients must demonstrate donor hematopoietic recovery and the absence of ongoing grade 2 or higher GVHD. For DC generation, donor-derived adherent mononuclear cells are cultured with GM-CSF, IL-4 and TNFa. Vaccine is administered subcutaneously starting day 70-100 post-transplant. 2 vaccines are given at 3 week intervals, in conjunction with 100 mcg GMCSF daily at the vaccine site for 4 days. A booster vaccine is given 30-60 days following the taper of immune suppression, in the absence of GVHD. Profiling of the immune microenvironment using single cell RNA sequencing from samples obtained before and after vaccination is being carried out. 17 participants have been enrolled. The median age was 59 years (range 23-74). 15 patients were enrolled to cohort A: 8 were transplanted with a matched unrelated donor and 7 were transplanted with a matched sibling donor. 2 participants were enrolled to cohort B. The median yield of leukemia cells was 207x10 6 (range 80-818x10 6)and mean viability was 96.5%. The median yield of DCs was 133x10 6 (range 29-182x10 6) and mean viability 72%. Fusion vaccine was successfully generated in 14/16 patients. One patient had insufficient DC, one patient relapsed prior to leukapheresis and one vaccine is currently in process. Mean fusion efficiency was 52% with viability of 78.6%. Mean fusion vaccine dose was 4.36 x10 6 cells. 3 patients from whom vaccine was generated did not meet eligibility to initiate vaccination due to ongoing toxicity following transplant or GVHD. 11 participants have initiated vaccine administration and are evaluable for toxicity and response. The most common side effects have been vaccine site reactions (n=10 grade 1, n=2 grade 2). 7 patients developed GVHD that was determined to be possibly related to vaccination, at a median time of 19 days after vaccination (range 5-70 days). 2 of these patients developed grade 2 acute GVHD of the skin, and 5 developed chronic GVHD affecting one to up to four organ systems ranging from mild to severe. There were 5 additional GVHD events with a median time of 115 days post vaccination (range 91-126 days), assessed as unlikely related or unrelated to vaccine based on timing of onset. 10 of 11 evaluable patients remain in a CR at a median time of 21 months post-transplant (range 6-33 months). One patient died of relapsed disease 15 months post transplant and another died of GVHD and infection unrelated to vaccine 21 months post transplant. Vaccination using patient-derived autologous leukemia cells and donor derived DC isolated following engraftment of hematopoietic cells appears safe and feasible. Toxicity of vaccination has included injection site reactions as well as graft versus host disease, primarily mild to moderate severity. Outcomes to date demonstrate that vaccination post-transplant may be a promising strategy to reduce relapse as 10 of 11 vaccinated patients remain relapse free. However this approach is limited to patients who have not had early relapse or early GVHD post-transplant. Immune correlates, including single cell RNA sequencing of the immune milieu, are ongoing. Disclosures Stone: Abbvie: Consultancy; Actinium: Membership on an entity's Board of Directors or advisory committees; Agios: Consultancy, Research Funding; Amgen: Membership on an entity's Board of Directors or advisory committees; Aprea: Consultancy; Arog: Consultancy, Research Funding; Astellas: Membership on an entity's Board of Directors or advisory committees; BerGen Bio: Membership on an entity's Board of Directors or advisory committees; Boston Pharmaceuticals: Consultancy; Bristol Meyers Squibb: Consultancy; Celgene: Consultancy; Elevate Bio: Membership on an entity's Board of Directors or advisory committees; Foghorn Therapeutics: Consultancy; Gemoab: Membership on an entity's Board of Directors or advisory committees; Glaxo Smith Kline: Consultancy; Innate: Consultancy; Janssen: Consultancy; Jazz: Consultancy; Macrogenics: Consultancy; Novartis: Consultancy, Research Funding; OncoNova: Consultancy; Syndax: Membership on an entity's Board of Directors or advisory committees; Syntrix/ACI: Membership on an entity's Board of Directors or advisory committees; Syros: Membership on an entity's Board of Directors or advisory committees; Takeda: Consultancy. Soiffer: Takeda: Consultancy; Jasper: Consultancy; Jazz Pharmaceuticals, USA: Consultancy; Precision Biosciences, USA: Consultancy; Juno Therapeutics, USA: Other: Data Safety Monitoring Board; Kiadis, Netherlands: Membership on an entity's Board of Directors or advisory committees; Rheos Therapeutics, USA: Consultancy; Gilead, USA: Other: Career Development Award Committee; NMPD - Be the Match, USA: Membership on an entity's Board of Directors or advisory committees. Stroopinsky: The Blackstone Group: Consultancy. Romee: Glycostem: Membership on an entity's Board of Directors or advisory committees; Crispr Therapeutics: Research Funding. Neuberg: Madrigal Pharmaceuticals: Other: Stock ownership; Pharmacyclics: Research Funding. Kufe: Canbas: Consultancy; Hillstream BioPharma: Current equity holder in publicly-traded company; Genus Oncology: Current equity holder in publicly-traded company; REATA: Consultancy, Current equity holder in publicly-traded company. Avigan: Chugai: Membership on an entity's Board of Directors or advisory committees; Partner Tx: Membership on an entity's Board of Directors or advisory committees; Karyopharm: Membership on an entity's Board of Directors or advisory committees; Parexcel: Consultancy; Janssen: Consultancy; Legend Biotech: Membership on an entity's Board of Directors or advisory committees; Pharmacyclics: Research Funding; Bristol-Myers Squibb: Membership on an entity's Board of Directors or advisory committees; Kite Pharma: Consultancy, Research Funding; Takeda: Membership on an entity's Board of Directors or advisory committees; Juno: Membership on an entity's Board of Directors or advisory committees; Takeda: Consultancy; Sanofi: Consultancy; Aviv MedTech Ltd: Membership on an entity's Board of Directors or advisory committees; Celgene: Membership on an entity's Board of Directors or advisory committees, Research Funding. Rosenblatt: Wolters Kluwer Health: Consultancy, Patents & Royalties; Parexel: Consultancy; Karyopharm: Membership on an entity's Board of Directors or advisory committees; Imaging Endpoints: Consultancy; Bristol-Myers Squibb: Research Funding; Attivare Therapeutics: Consultancy.

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Patnaik, Mrinal M., Haris Ali, Eunice S. Wang, Abdulraheem Yacoub, Vikas Gupta, Sangmin Lee, Gary J. Schiller et al. "Tagraxofusp (SL-401) in Patients with Chronic Myelomonocytic Leukemia (CMML): Updated Results of an Ongoing Phase 1/2 Trial". Blood 138, Supplement 1 (5 de noviembre de 2021): 538. http://dx.doi.org/10.1182/blood-2021-147827.

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Abstract Introduction CMML is a clonal hematopoietic stem cell disorder with overlapping features of myelodysplastic syndromes (MDS) and myeloproliferative neoplasms (MPN). Current therapeutic options for patients (pts) with CMML are limited, leaving a significant unmet medical need. Pts classified to have the MPN subtype, compared with the MDS subtype, and those with high-risk genetic features tend to have a higher rate of transformation to acute myeloid leukemia (AML) and median survival of 2-3 years. The seminal observation of increased expression of CD123 (interleukin-3Rα) on leukemia stem cells and clonal plasmacytoid dendritic cells led to the clinical investigation of a novel CD123-targeted agent, tagraxofusp (TAG, SL-401), in CD123-positive hematologic malignancies, including blastic plasmacytoid dendritic cell neoplasm (BPDCN), CMML, AML, and myelofibrosis. TAG demonstrated robust clinical activity in pts with BPDCN and is now approved in the US and EU for this indication. Data from an ongoing phase 1/2 study of TAG monotherapy for pts with relapsed/refractory (R/R) CMML (NCT02268253) also demonstrated clinical activity (Patnaik et al. J Clin Oncol 2019;37: abstr 7059). Herein, we present updated safety and efficacy results of this study in first-line (1L) high-risk and R/R pts. Methods A multicenter, multistage, phase 1/2 trial was designed initially to assess the safety and efficacy of TAG monotherapy in adult pts with R/R CMML (Stages 1 and 2), and subsequently expanded to include 1L high-risk and R/R pts (Stage 3A). Clinical responses were initially assessed by the International Working Group/MDS 2006 criteria, and subsequently amended to the MDS/MPN 2015 criteria. Splenomegaly was assessed by palpation in Stages 1 and 2, and by palpation and imaging in Stage 3A. TAG was administered as a daily IV infusion at 7, 9, or 12 mcg/kg on days (d)1-3 every 21 d (cycles [C]1-4), 28 d (C5-7), and 42 d (C8 and beyond) in Stage 1, and at 12 mcg/kg (recommended phase 2 dose defined in Stage 1) every 21 d (C1-4) and 28 d (C5 and beyond) in Stages 2-3A. Results As of July 2021, 36 pts have been enrolled, comprising 20 pts with CMML-1 and 16 with CMML-2; median age is 69 years (range 42-81); 75% are male. Twenty-three (64%) pts had either high- or intermediate-risk genetics based on CPSS, GFM, MMM, or ELN risk-stratification systems. Prior therapies included HMA in 16 (43%) pts, allogeneic stem cell transplantation (allo-SCT) in 3 (8%), and other in 12 (32%); 7 (19%) pts were high-risk and treatment naive. Overall, 16 (44%) pts had baseline palpable splenomegaly, of whom 12 pts' spleen size was ≥5 cm below left costal margin. The most common (in ≥20% of pts, n=34) treatment-related adverse events (TRAEs) were hypoalbuminemia (26%), thrombocytopenia (24%), nausea (24%), and capillary leak syndrome (CLS, 21%; grade 2, n=4; grade 3, n=3). Grade ≥3 TRAEs were thrombocytopenia (21%), CLS (9%), anemia (9%), and nausea (3%). Discontinuation rate due to TRAEs was low (n=1). Overall, 4 of 36 (11%) pts achieved bone marrow morphologic complete responses (BMCRs), of whom 1 pt was bridged to allo-SCT; all 4 pts had splenomegaly at baseline. Noteworthy, 2 of the 4 BMCRs were observed in pts with high-risk genetic features. Fifteen (42%) pts with baseline splenomegaly had spleen responses; 9 (60%) pts had a ≥50% reduction in spleen size, including 5 (42%) with splenomegaly ≥5 cm at baseline. Median follow-up was 11 weeks (range 1-163 weeks). In the Stage 3A cohort, 2 high-risk 1L pts had BM partial remissions, with 1 also having clinical benefit. Three pts had a spleen volume reduction by MRI scans following C1 (range 7%-36%) and 1 pt had a reduction of 57% after C4. While on study, none of the 7 pts (2 transfusion dependent at baseline) have required blood or platelet transfusions. Updated results on Stage 3A, including total symptom scores, will be presented. Conclusions Ongoing results in pts with CMML demonstrate TAG monotherapy has significant clinical activity in 1L pts with high-risk disease as well as those with R/R disease. The responses were particularly notable in those with baseline splenomegaly. As Stage 3A of the trial continues, mutational correlates and BM PDCs are being assessed. TAG treatment is well-tolerated, with a manageable and predictable safety profile. Overall, the data suggest that TAG may offer a novel targeted approach for pts with CMML. Stage 3A of the trial continues. Disclosures Patnaik: Kura Oncology: Research Funding; Stemline Therapeutics: Membership on an entity's Board of Directors or advisory committees; Stemline Therapeutics: Membership on an entity's Board of Directors or advisory committees. Ali: BMS: Speakers Bureau; Incyte: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; CTI BioPharma: Membership on an entity's Board of Directors or advisory committees. Wang: Kite Pharmaceuticals: Consultancy, Honoraria, Other: Advisory Board; Mana Therapeutics: Consultancy, Honoraria; Novartis: Consultancy, Honoraria, Other: Advisory Board; BMS/Celgene: Membership on an entity's Board of Directors or advisory committees; Stemline Therapeutics: Consultancy, Honoraria, Other: Advisory board, Speakers Bureau; Genentech: Membership on an entity's Board of Directors or advisory committees; DAVA Oncology: Consultancy, Speakers Bureau; Takeda: Consultancy, Honoraria, Other: Advisory board; Kura Oncology: Consultancy, Honoraria, Other: Advisory board, steering committee, Speakers Bureau; Pfizer: Consultancy, Honoraria, Other: Advisory Board, Speakers Bureau; Jazz Pharmaceuticals: Consultancy, Honoraria, Other: Advisory Board; GlaxoSmithKline: Consultancy, Honoraria, Other: Advisory Board; Astellas: Consultancy, Membership on an entity's Board of Directors or advisory committees; AbbVie: Consultancy, Membership on an entity's Board of Directors or advisory committees; Rafael Pharmaceuticals: Other: Data safety monitoring committee; Gilead: Consultancy, Honoraria, Other: Advisory board; Daiichi Sankyo: Consultancy, Honoraria, Other: Advisory board; PTC Therapeutics: Consultancy, Honoraria, Other: Advisory board; Genentech: Consultancy; MacroGenics: Consultancy. Yacoub: Incyte: Consultancy, Honoraria, Speakers Bureau; CTI Biopharma: Membership on an entity's Board of Directors or advisory committees; ACCELERON PHARMA: Membership on an entity's Board of Directors or advisory committees; Agios: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Dynavex: Current equity holder in publicly-traded company; Cara: Current equity holder in publicly-traded company; Ardelyx: Current equity holder in publicly-traded company; Seattle Genetics: Honoraria, Speakers Bureau; Novartis: Consultancy, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Hylapharm: Current equity holder in publicly-traded company. Gupta: Pfizer: Consultancy; BMS-Celgene: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees; Novartis: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; AbbVie: Consultancy, Honoraria; Incyte: Honoraria, Research Funding; Sierra Oncology: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees; Constellation Pharma: Consultancy, Honoraria; Roche: Consultancy. Lee: AstraZeneca: Consultancy, Membership on an entity's Board of Directors or advisory committees; BMS: Consultancy, Membership on an entity's Board of Directors or advisory committees; Innate: Consultancy, Membership on an entity's Board of Directors or advisory committees; Pin Therapeutics: Consultancy, Membership on an entity's Board of Directors or advisory committees. Schiller: Kite/Gilead: Honoraria, Research Funding, Speakers Bureau; Agios: Consultancy, Research Funding, Speakers Bureau; FujiFilm: Research Funding; PrECOG: Research Funding; Karyopharm: Research Funding; Actinium Pharmaceuticals, Inc: Research Funding; Sangamo: Research Funding; Tolero: Research Funding; Incyte: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau; Geron: Research Funding; Stemline Therapeutics, Inc.: Honoraria, Research Funding, Speakers Bureau; Takeda: Research Funding; Constellation Pharmaceuticals: Research Funding; Trovagene: Research Funding; Actuate: Research Funding; BMS/Celgene: Consultancy, Current equity holder in publicly-traded company, Research Funding, Speakers Bureau; Amgen: Consultancy, Current equity holder in publicly-traded company, Honoraria, Research Funding, Speakers Bureau; Regimmune: Research Funding; Delta-Fly: Research Funding; Genentech-Roche: Research Funding; Gamida Cell Ltd.: Research Funding; Astellas: Honoraria, Research Funding, Speakers Bureau; Celator: Research Funding; Daiichi-Sankyo: Research Funding; Arog: Research Funding; Forma: Research Funding; Samus: Research Funding; Deciphera: Research Funding; Jazz: Consultancy, Honoraria, Research Funding, Speakers Bureau; Elevate: Research Funding; Bio: Research Funding; Ono-UK: Consultancy, Research Funding; Abbvie: Research Funding; Mateon: Research Funding; Pfizer: Current equity holder in publicly-traded company, Research Funding; Onconova: Research Funding; Novartis: Consultancy, Research Funding; Sanofi: Honoraria, Research Funding, Speakers Bureau; Pharma: Consultancy; Johnson & Johnson: Current equity holder in publicly-traded company; Biomed Valley Discoveries: Research Funding; Eli Lilly: Research Funding; ASH foundation: Other: Chair-unpaid; Sellas: Research Funding; Ono: Consultancy; Incyte: Consultancy; Ariad: Research Funding; AstraZeneca: Consultancy; Kaiser Permanente: Consultancy; Cyclacel: Research Funding; MedImmune: Research Funding; Ambit: Research Funding; Leukemia & Lymphoma Society: Research Funding; Bluebird Bio: Research Funding; Boehringer-Ingleheim: Research Funding; Cellerant: Research Funding; CTI Biopharma: Research Funding; Janssen: Research Funding; Kura Oncology: Research Funding; Pharmacyclics: Honoraria, Speakers Bureau; Millennium: Research Funding; National Marrow Donor Program: Research Funding; NIH: Research Funding; Onyx: Research Funding; Pharmamar: Research Funding; UC Davis: Research Funding; UCSD: Research Funding; Evidera: Consultancy; NCI: Consultancy; Novartis: Speakers Bureau. Foran: takeda: Research Funding; taiho: Honoraria; syros: Honoraria; boehringer ingelheim: Research Funding; trillium: Research Funding; abbvie: Research Funding; aptose: Research Funding; actinium: Research Funding; kura: Research Funding; sanofi aventis: Honoraria; gamida: Honoraria; certara: Honoraria; servier: Honoraria; revolution medicine: Honoraria; bms: Honoraria; pfizer: Honoraria; novartis: Honoraria; OncLive: Honoraria; h3bioscience: Research Funding; aprea: Research Funding; sellas: Research Funding; stemline: Research Funding. Brooks: Stemline Therapeutics: Current Employment. Mughal: Oxford University Press, Informa: Other: financial benefit and/or patents ; Stemline: Current Employment, Current holder of stock options in a privately-held company. Pemmaraju: Cellectis S.A. ADR: Other, Research Funding; Daiichi Sankyo, Inc.: Other, Research Funding; HemOnc Times/Oncology Times: Membership on an entity's Board of Directors or advisory committees; CareDx, Inc.: Consultancy; Aptitude Health: Consultancy; ASH Communications Committee: Membership on an entity's Board of Directors or advisory committees; ASCO Leukemia Advisory Panel: Membership on an entity's Board of Directors or advisory committees; Springer Science + Business Media: Other; Bristol-Myers Squibb Co.: Consultancy; Sager Strong Foundation: Other; Dan's House of Hope: Membership on an entity's Board of Directors or advisory committees; ImmunoGen, Inc: Consultancy; Samus: Other, Research Funding; Plexxicon: Other, Research Funding; Blueprint Medicines: Consultancy; Clearview Healthcare Partners: Consultancy; DAVA Oncology: Consultancy; Roche Diagnostics: Consultancy; MustangBio: Consultancy, Other; Abbvie Pharmaceuticals: Consultancy, Membership on an entity's Board of Directors or advisory committees, Other, Research Funding; Celgene Corporation: Consultancy; Stemline Therapeutics, Inc.: Consultancy, Membership on an entity's Board of Directors or advisory committees, Other, Research Funding; LFB Biotechnologies: Consultancy; Novartis Pharmaceuticals: Consultancy, Other: Research Support, Research Funding; Incyte: Consultancy; Affymetrix: Consultancy, Research Funding; Protagonist Therapeutics, Inc.: Consultancy; Pacylex Pharmaceuticals: Consultancy.

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SIMONSON, DONALD C., MANUEL TASO, COLLEEN MCGRATH, STEPHANIE A. WALDMAN, FOTINI PAPADOPOULOU y DAVID C. ALSOP. "359-OR: Imaging Pancreatic Blood Flow during Stimulation of Insulin Secretion in Humans". Diabetes 71, Supplement_1 (1 de junio de 2022). http://dx.doi.org/10.2337/db22-359-or.

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Non-invasive imaging of endocrine pancreatic function could provide valuable insights into the magnitude and temporal pattern of β-cell dysfunction in diabetes. Islets comprise 1-2% of pancreatic mass, but receive about 10-20% of pancreatic blood flow, which increases further during stimulation of insulin secretion. We examined the relationship between pancreatic blood flow (PBF) and insulin secretory dynamics in 12 healthy volunteers (6M / 6F, age = 29 ± 5 yrs, BMI = 24.0 ± 2.7 kg/m², HbA1c = 5.1 ± 0.3 %, FPG = 88 ± mg/dl, fasting insulin = 3.7 ± 2.3 μU/ml) . PBF was measured by pseudo-continuous arterial spin labeling (ASL) MRI, with the labeling plane positioned 5-6 cm superior to the imaging slice to label blood in the descending aorta. Fasting subjects were placed in a 3T scanner, and PBF was measured during 1) a 15 min basal period, 2) a +100 mg/dl hyperglycemic clamp for 40 min, followed by 3) a 5 gm bolus of arginine to assess maximal acute insulin response (AIRmax) . First phase (0-min) insulin response to hyperglycemia was 181 ± 96 μU/ml · min, and AIRmax after arginine + hyperglycemia (40-50 min) was 1097 ± 629 μU/ml · min. Basal PBF (188 ± 53 ml/100 gm/min) increased during first phase insulin release, peaking at 212 ± 66 at 12 min, subsequently returned to basal levels (176 ± 59) from 10-40 min during sustained hyperglycemia,and peaked again at 2± 62 at 2 min after arginine. Although there were no significant correlations between glucose, insulin or c-peptide levels and PBF, time-series Granger causality analysis demonstrated that the time-derivative of c-peptide and insulin concentrations, reflectingacute changes in insulin secretion, preceded the increase in PBF (p=0.03 for d[c-peptide]/dt, and p = 0.for d[insulin]/dt) . Conclusions: 1) Changes in PBF during stimulation of insulin secretion in humans can be imaged non-invasively by ASL, 2) Insulin secretion precedes changes in PBF, and 3) The rate of change in insulin and c-peptide release predicts subsequent modulation of PBF. Disclosure D.C.Simonson: Stock/Shareholder; GI Windows, Phase V Technologies, Inc. M.Taso: Research Support; GE Healthcare Systems. C.Mcgrath: None. S.A.Waldman: None. F.Papadopoulou: None. D.C.Alsop: Other Relationship; GE Healthcare Systems, Hitachi, Ltd., Philips Healthcare, Siemens, UIH America, Research Support; GE Healthcare Systems.

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Benders, Stefan y Bernhard Blümich. "Applications of magnetic resonance imaging in chemical engineering". Physical Sciences Reviews 4, n.º 10 (9 de mayo de 2019). http://dx.doi.org/10.1515/psr-2018-0177.

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Abstract While there are many techniques to study phenomena that occur in chemical engineering applications, magnetic resonance imaging (MRI) receives increasing scientific interest. Its non-invasive nature and wealth of parameters with the ability to generate functional images and contrast favors the use of MRI for many purposes, in particular investigations of dynamic phenomena, since it is very sensitive to motion. Recent progress in flow-MRI has led to shorter acquisition times and enabled studies of transient phenomena. Reactive systems can easily be imaged if NMR parameters such as relaxation change along the reaction coordinate. Moreover, materials and devices can be examined, such as batteries by mapping the magnetic field around them.

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Kuzio, Olivia R. y Susan P. Farnand. "Comparing Practical Spectral Imaging Methods for Cultural Heritage Studio Photography". Journal on Computing and Cultural Heritage, 25 de julio de 2022. http://dx.doi.org/10.1145/3531019.

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Two practical methods for implementing spectral imaging within the framework of museum studio photography were investigated. Imaging was carried out using a consumer RGB digital camera paired with either 1) colored glass filters and a broadband source or 2) optimized multichannel LED illumination, yielding five or six spectral image bands, respectively. Color targets were used to develop and verify profiles for transforming between the multiband camera signals and final color managed images. The filter-based and LED-based profiles were assessed quantitatively for color accuracy using color difference statistics, and several paintings were imaged and rendered using the profiles as a visual demonstration of the differences. While both were superior to conventional RGB imaging, the LED-based method outperformed the filter-based method for accurate reproduction of independent data. This supplements practicality and cost considerations that are informing the development of accessible spectral imaging strategies for highly color accurate museum studio photography.

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"Adept Technology selects Matrox Electronic Systems Ltd as supplier of imaging hardware". Industrial Robot: An International Journal 26, n.º 5 (julio de 1999). http://dx.doi.org/10.1108/ir.1999.04926eab.008.

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OE, YUKI, TAKAHIRO TAKASE, KYUYONG CHO, KOJI OGAWA, YUMA EBIHARA, AIKA MIYA, HIROSHI NOMOTO et al. "1424-P: Impact of Laparoscopic Sleeve Gastrectomy on Nonalcoholic Fatty Liver Disease in Obese Patients with Type 2 Diabetes: Prospective Observational Study". Diabetes 71, Supplement_1 (1 de junio de 2022). http://dx.doi.org/10.2337/db22-1424-p.

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Background: Bariatric/metabolic surgery is a valid treatment option for patients with obesity, type 2 diabetes (T2DM) and nonalcoholic fatty liver disease (NAFLD) . Although magnetic resonance imaging (MRI) is more accurate, the evaluation of NAFLD is generally limited to ultrasonography and various scoring systems. Here, we show a therapeutic effect of laparoscopic sleeve gastrectomy (LSG) on NAFLD in Japanese patients with T2DM using MRI. Methods: We conducted a prospective observational study of Japanese patients with obesity, T2DM, and NAFLD over 1 year (UMIN000034667) . The participants were 20 surgically (LSG group) and 20 medically (control group) treated patients. We compared various parameters at baseline and 1 year later in the two groups. The primary outcome was the change in the MRI proton density fat fraction and elasticity of the liver. The secondary outcomes were changes in metabolic parameters, including body mass index (BMI) , HbA1c, and diabetic remission rate. Results: To date, 28 patients (LSG 15, control 13) have completed the study. Their baseline BMIs were LSG 39.5 [35.5, 45.1] kg/m2 and control 35.9 [32.6, 43.6] kg/m2 (P=0.12) . One year after surgery, the index of hepatic steatosis, MRI proton density fat fraction (LSG −13.3±8.4%, control −0.8±5.5%, P<0.01) , was significantly lower in the LSG group. A second index, stiffness on MRI elastography (LSG −0.2 [−0.3, 0.1] kPa, control −0.[−0.35, 0.4] kPa, P=0.60) tended to be lower. In addition, BMI (LSG −9.5±3.2 kg/m2, control −0.1±0.6 kg/m2; P<0.01) and HbA1c (LSG −1.4±1.0%, control 0.3±0.8 kg/m2; P<0.01) were significantly lower. The postoperative diabetic remission rate was 86.7%. Conclusion: We have shown that LSG causes marked weight loss and diabetic remission in many patients. NAFLD was also markedly ameliorated, especially hepatic steatosis, although a longer study may be required to detect an improvement in fibrosis. Disclosure Y.Oe: None. T.Atsumi: Consultant; AbbVie Inc., AstraZeneca, MEDICAL & BIOLOGICAL LABORATORIES CO., Nippon Boehringer Ingelheim Co. Ltd., Novartis Pharma K.K., Ono Pharmaceutical Co., Ltd., Pfizer Inc., Research Support; AbbVie Inc., Alexion Pharmaceuticals, Inc., Astellas Pharma Inc., Chugai Pharmaceutical Co., Ltd., Daiichi Sankyo, Mitsubishi Tanabe Pharma Corporation, Nippon Boehringer Ingelheim Co. Ltd., Otsuka Pharmaceutical Co., Ltd., Pfizer Inc., Taiho Pharmaceutical Co. Ltd., Takeda Pharmaceutical Company Limited, Teijin Pharma Limited, Speaker's Bureau; AbbVie Inc., Astellas Pharma Inc., Bristol-Myers Squibb Company, Chugai Pharmaceutical Co., Ltd., Daiichi Sankyo, Eisai Co., Ltd., Eli Lilly and Company, Kyowa Kirin Co., Ltd., Mitsubishi Tanabe Pharma Corporation, Novartis Pharma K.K., Pfizer Inc., Taiho Pharmaceutical Co. Ltd., Takeda Pharmaceutical Company Limited, UCB, Inc. H.Miyoshi: Research Support; Abbott Japan Co., Ltd., Boehringer Ingelheim International GmbH, Daiichi Sankyo, Kowa Company, Ltd., LifeScan, Mitsubishi Tanabe Pharma Corporation, Novo Nordisk, Ono Pharmaceutical Co., Ltd., Sumitomo Dainippon Pharma Co., Ltd., Taisho Pharmaceutical Holdings Co., Ltd., Speaker's Bureau; Astellas Pharma Inc., Boehringer Ingelheim International GmbH, Eli Lilly and Company, Kowa Company, Ltd., Merck & Co., Inc., Mitsubishi Tanabe Pharma Corporation, Novo Nordisk, Ono Pharmaceutical Co., Ltd., Sanofi K.K., Sumitomo Dainippon Pharma Co., Ltd., Taisho Pharmaceutical Holdings Co., Ltd. T.Takase: None. K.Cho: None. K.Ogawa: None. Y.Ebihara: None. A.Miya: None. H.Nomoto: None. H.Kameda: None. A.Nakamura: Research Support; Kissei Pharmaceutical Co., Ltd., MSD, Nippon Boehringer Ingelheim, Taisho Pharmaceutical Holdings Co., Ltd.

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Wolf, Elias V., Chiara Gnasso, U. Joseph Schoepf, Moritz C. Halfmann, Jim O'Doherty, Emese Zsarnoczay, Akos Varga-Szemes, Tilman Emrich y Nicola Fink. "Intra-individual comparison of coronary artery stenosis measurements between energy-integrating detector CT and photon-counting detector CT". Imaging, 25 de julio de 2023. http://dx.doi.org/10.1556/1647.2023.00156.

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AbstractPurposeTo compare intra-individual percentage diameter stenosis (PDS) measurements of coronary artery stenoses between energy-integrating detector computed tomography (EID-CT) and a clinical photon-counting detector computed tomography (PCD-CT) systems using similar acquisition and reconstruction settings.MethodsPatients (n = 23, mean age of 65 ± 12.1 years, out of these 16 (69.6%) male) were imaged on a conventional EID- and a clinical PCD-CT system with a median of 5.5 (3.0–12.5) days apart. Sequential CCTA scans were acquired and reconstructed using similar settings, including a vascular Bv36 kernel, a tube voltage of 110 kVp for EID-CT vs 120 kVp for PCD-CT, a slice thickness of 0.5 for EID-CT vs 0.6 for PCD-CT, and an iterative reconstruction strength of 3 on EID-CT vs a virtual monoenergetic reconstruction at 55 keV and quantum iterative reconstruction level of 3 on PCD-CT. Radiation dose, contrast volume, and injection parameters were matched as similarly as possible between the systems. PDS measurements were performed according to the coronary artery disease reporting and data system (CAD-RADS) by two trained readers and compared between the different modalities using the Wilcoxon rank sum test, Spearman correlation, and Bland-Altman analysis.ResultsPCD-CT measured significantly lower PDS values than EID-CT [PDSEID-CT: 45.1% (35.1%–64.0%) vs. PDSPCD-CT 44.2% (32.4%–61.0%), P < 0.0001]. This difference led to a mean bias of 1.8 (LoA −3.0/6.5) with an excellent ICC (0.99) value among EID- and PCD-CT. The mean intra-individual deviation between the examinations was 1.8% between the scanners. This led to CAD-RADS re-classification in 3/23 cases (13.0%, new-lower class) for the first reader, and in 4/23 cases (13.0%, new-lower and 4.4%, new-higher class) for the second reader. Inter-reader agreement between the two readers for each stenosis was very strong (ICC = 0.98).ConclusionsCoronary artery stenosis measurements from PCD-CT correlate strongly to EID-CT-based measurements, despite the tendency of the measurement from PCD-CT being lower. This difference led to a change in CAD-RADS classification in 17.4% of patients. The effects on clinical decision-making, downstream testing, and prognosis have to be evaluated in future studies.

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"Company News". Asia-Pacific Biotech News 06, n.º 25 (9 de diciembre de 2002): 976–89. http://dx.doi.org/10.1142/s0219030302001994.

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Progen’s Anti-cancer Drug Shows Promising Human Trial Data. Acrux Reports Progress for Treatment of Female Sexual Dysfunction. Clinical Reagent Ready for Agenix’s Blood Clot Imaging Project. Austcancer’s Vaccine Human Trials Show Strong Results. Shanghai Desano to Sell Domestically Produced AIDS Drug. Shanghai Boxing Develops Bio Chip that Identifies GM Plants. Ranbaxy In-licenses New Biological Entity for Brain Cancer. Wockhardt and Daiichi in Collaboration for Hemorrhage Drug. Nicholas Piramal to Merge with Global Drugs. Shionogi in Agreement with Pharmagene for Target and Compound Validation Capabilities. Eisai’s Treatment of H. pylori Infection Approved by US. Tanabe Seiyaku and Altana in Roflumilast Cooperation in Japan. In2Gen Co. Ltd. InBioNET Corp. Agriquality Buys out Melbourne Gene Lab. Singapore Consulting Practice Brings Biomedical Firms to Asia. A-Bio Pharma is Singapore’s First Commercial Scale Biologics Manufacturer. Abbott and MerLion in Drug Discovery Collaboration. Lilly Systems Biology Research Center Established in Singapore.

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Novara, Matteo, Daniel Schanz, Reinhard Geisler, Janos Agocs, Felix Eich, Matthew Bross, Christian Kähler y Andreas Schröder. "Investigation of turbulent boundary layer flows with adverse pressure gradient by means of 3D Lagrangian particle tracking with Shake-The-Box". 14th International Symposium on Particle Image Velocimetry 1, n.º 1 (1 de agosto de 2021). http://dx.doi.org/10.18409/ispiv.v1i1.70.

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A large-scale 3D Lagrangian particle tracking (LPT) investigation of a turbulent boundary layer (TBL) flow developing across different pressure gradient regions is presented in this study. Three high-speed multi-camera imaging systems, LED illumination and helium-filled soap bubbles (HFSB) tracers have been adopted to produce time-resolved sequences of particle images over a large volume encompassing approximately 3 m in the streamwise direction, 0:8 m in the spanwise direction and 0:25 m in the wall-normal direction. Individual tracers have been reconstructed and tracked within the imaged volume by means of the Shake-The-Box algorithm (STB, Schanz et al. (2016)); the FlowFit data assimilation algorithm (Gesemann et al. (2016)) has been used to evaluate the spatial velocity gradients and to interpolate the scattered LPT results onto a regular grid. Thanks to the large size of the investigated volume and to the time-resolved nature of the recorded images, the entire spatial extent of the large-scale coherent motions within the logarithmic region of the TBL (i.e. superstructures) could be captured and their dynamics investigated during their development over several boundary layer thickness in the streamwise direction, from the zero pressure gradient region (ZPG) to the adverse pressure gradient region (APG). Two free-stream velocities were investigated, namely 7 and 14m=s, corresponding to Ret ~ 3,000 and 5,000 respectively. The results confirm the location and scale of the elongated high- and low-momentum structures in the logarithmic region, as well as their meandering in the spanwise direction. Two-point correlation statistics show that the width and spacing of the superstructures are not affected by the transition from the ZPG to the APG region. The analysis of the instantaneous flow realizations from both a Lagrangian and Eulerian perspective indicates the presence of significant fluid particle elements exchange across the interfaces of the large-scale structures.

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van Sluis, Joyce, Johannes H. van Snick, Adrienne H. Brouwers, Walter Noordzij, Rudi A. J. O. Dierckx, Ronald J. H. Borra, Riemer H. J. A. Slart et al. "EARL compliance and imaging optimisation on the Biograph Vision Quadra PET/CT using phantom and clinical data". European Journal of Nuclear Medicine and Molecular Imaging, 25 de julio de 2022. http://dx.doi.org/10.1007/s00259-022-05919-1.

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Abstract Purpose Current European Association of Nuclear Medicine (EANM) Research Ltd. (EARL) guidelines for the standardisation of PET imaging developed for conventional systems have not yet been adjusted for long axial field-of-view (LAFOV) systems. In order to use the LAFOV Siemens Biograph Vision Quadra PET/CT (Siemens Healthineers, Knoxville, TN, USA) in multicentre research and harmonised clinical use, compliance to EARL specifications for 18F-FDG tumour imaging was explored in the current study. Additional tests at various locations throughout the LAFOV and the use of shorter scan durations were included. Furthermore, clinical data were collected to further explore and validate the effects of reducing scan duration on semi-quantitative PET image biomarker accuracy and precision when using EARL-compliant reconstruction settings. Methods EARL compliance phantom measurements were performed using the NEMA image quality phantom both in the centre and at various locations throughout the LAFOV. PET data (maximum ring difference (MRD) = 85) were reconstructed using various reconstruction parameters and reprocessed to obtain images at shorter scan durations. Maximum, mean and peak activity concentration recovery coefficients (RC) were obtained for each sphere and compared to EARL standards specifications. Additionally, PET data (MRD = 85) of 10 oncological patients were acquired and reconstructed using various reconstruction settings and reprocessed from 10 min listmode acquisition into shorter scan durations. Per dataset, SUVs were derived from tumour lesions and healthy tissues. ANOVA repeated measures were performed to explore differences in lesion SUVmax and SUVpeak. Wilcoxon signed-rank tests were performed to evaluate differences in background SUVpeak and SUVmean between scan durations. The coefficient of variation (COV) was calculated to characterise noise. Results Phantom measurements showed EARL compliance for all positions throughout the LAFOV for all scan durations. Regarding patient data, EARL-compliant images showed no clinically meaningful significant differences in lesion SUVmax and SUVpeak or background SUVmean and SUVpeak between scan durations. Here, COV only varied slightly. Conclusion Images obtained using the Vision Quadra PET/CT comply with EARL specifications. Scan duration and/or activity administration can be reduced up to a factor tenfold without the interference of increased noise.

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Laforest, Richard, Mehdi Khalighi, Yutaka Natsuaki, Abhejit Rajagopal, Dharshan Chandramohan, Darrin Byrd, Hongyu An et al. "Harmonization of PET image reconstruction parameters in simultaneous PET/MRI". EJNMMI Physics 8, n.º 1 (5 de noviembre de 2021). http://dx.doi.org/10.1186/s40658-021-00416-0.

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Abstract Objective Simultaneous PET/MRIs vary in their quantitative PET performance due to inherent differences in the physical systems and differences in the image reconstruction implementation. This variability in quantitative accuracy confounds the ability to meaningfully combine and compare data across scanners. In this work, we define image reconstruction parameters that lead to comparable contrast recovery curves across simultaneous PET/MRI systems. Method The NEMA NU-2 image quality phantom was imaged on one GE Signa and on one Siemens mMR PET/MRI scanner. The phantom was imaged at 9.7:1 contrast with standard spheres (diameter 10, 13, 17, 22, 28, 37 mm) and with custom spheres (diameter: 8.5, 11.5, 15, 25, 32.5, 44 mm) using a standardized methodology. Analysis was performed on a 30 min listmode data acquisition and on 6 realizations of 5 min from the listmode data. Images were reconstructed with the manufacturer provided iterative image reconstruction algorithms with and without point spread function (PSF) modeling. For both scanners, a post-reconstruction Gaussian filter of 3–7 mm in steps of 1 mm was applied. Attenuation correction was provided from a scaled computed tomography (CT) image of the phantom registered to the MR-based attenuation images and verified to align on the non-attenuation corrected PET images. For each of these image reconstruction parameter sets, contrast recovery coefficients (CRCs) were determined for the SUVmean, SUVmax and SUVpeak for each sphere. A hybrid metric combining the root-mean-squared discrepancy (RMSD) and the absolute CRC values was used to simultaneously optimize for best match in CRC between the two scanners while simultaneously weighting toward higher resolution reconstructions. The image reconstruction parameter set was identified as the best candidate reconstruction for each vendor for harmonized PET image reconstruction. Results The range of clinically relevant image reconstruction parameters demonstrated widely different quantitative performance across cameras. The best match of CRC curves was obtained at the lowest RMSD values with: for CRCmean, 2 iterations-7 mm filter on the GE Signa and 4 iterations-6 mm filter on the Siemens mMR, for CRCmax, 4 iterations-6 mm filter on the GE Signa, 4 iterations-5 mm filter on the Siemens mMR and for CRCpeak, 4 iterations-7 mm filter with PSF on the GE Signa and 4 iterations-7 mm filter on the Siemens mMR. Over all reconstructions, the RMSD between CRCs was 1.8%, 3.6% and 2.9% for CRC mean, max and peak, respectively. The solution of 2 iterations-3 mm on the GE Signa and 4 iterations-3 mm on Siemens mMR, both with PSF, led to simultaneous harmonization and with high CRC and low RMSD for CRC mean, max and peak with RMSD values of 2.8%, 5.8% and 3.2%, respectively. Conclusions For two commercially available PET/MRI scanners, user-selectable parameters that control iterative updates, image smoothing and PSF modeling provide a range of contrast recovery curves that allow harmonization in harmonization strategies of optimal match in CRC or high CRC values. This work demonstrates that nearly identical CRC curves can be obtained on different commercially available scanners by selecting appropriate image reconstruction parameters.

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Wang, Zhaorui, Xiaowei Yang, Jingjing Wang, Peng Liu, Yubo Pan, Chunguang Han y Jing Pei. "Real-Time In Situ Navigation System With Indocyanine Green Fluorescence for Sentinel Lymph Node Biopsy in Patients With Breast Cancer". Frontiers in Oncology 11 (5 de mayo de 2021). http://dx.doi.org/10.3389/fonc.2021.621914.

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BackgroundThe naked-eye invisibility of indocyanine green fluorescence limits the application of near-infrared fluorescence imaging (NIR) systems for real-time navigation during sentinel lymph node biopsy (SLNB) in patients with breast cancer undergoing surgery. This study aims to evaluate the effectiveness and safety of a novel NIR system in visualizing indocyanine green fluorescence images in the surgical field and the application value of combined methylene blue (MB) and the novel NIR system in SLNB.MethodsSixty patients with clinical node-negative breast cancer received indocyanine green (ICG) and MB as tracers. Two NIR system instruments, namely, lymphatic fluorescence imaging system (LFIS) designed by the University of Science and Technology of China and vascular imager by Langfang Mingde Medical Biotechnology Co., Ltd. (Langfang vascular imager), were used as navigation assistance to locate sentinel lymph nodes (SLNs). Excising the lymph nodes developed by both MB and ICG by two NIR systems or palpably suspicious as SLNs and undergoing rapid pathological examination.ResultsBoth instruments exhibited 95% (57/60) success for real-time lymphatic fluorescent images. A total of 186 SLNs were identified, of which two were pathologically confirmed as lacking any lymph node tissue. SLN identification rate was 100% (184/184) for MB plus LFIS and 86.96% (160/184) for MB alone. The median number of SLNs identified by LFIS combined with MB was 3 (range of 1–8), which was significantly higher than that by MB alone at 2 (range 1–7) (P<0.05).ConclusionLFIS effectively detects SLNs in breast cancer, projects the fluorescence signals during surgery, and provides a continuous surgical navigation system without the need for a remote monitor. The ICG method navigated by combined LFIS and MB may be a promising alternative tracer for radioisotope in SLN mapping.Clinical Trial RegistrationThis clinical trial was registered with the China Clinical Trial Center, registration number ChiCTR2000039542.

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Humphries, Matthew P., Danny Kaye, Gaby Stankeviciute, Jacob Halliwell, Alexander I. Wright, Daljeet Bansal, David Brettle y Darren Treanor. "Development of a multi‐scanner facility for data acquisition for digital pathology artificial intelligence". Journal of Pathology, 10 de julio de 2024. http://dx.doi.org/10.1002/path.6326.

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AbstractWhole slide imaging (WSI) of pathology glass slides using high‐resolution scanners has enabled the large‐scale application of artificial intelligence (AI) in pathology, to support the detection and diagnosis of disease, potentially increasing efficiency and accuracy in tissue diagnosis. Despite the promise of AI, it has limitations. ‘Brittleness’ or sensitivity to variation in inputs necessitates that large amounts of data are used for training. AI is often trained on data from different scanners but not usually by replicating the same slide across scanners. The utilisation of multiple WSI instruments to produce digital replicas of the same slides will make more comprehensive datasets and may improve the robustness and generalisability of AI algorithms as well as reduce the overall data requirements of AI training. To this end, the National Pathology Imaging Cooperative (NPIC) has built the AI FORGE (Facilitating Opportunities for Robust Generalisable data Emulation), a unique multi‐scanner facility embedded in a clinical site in the NHS to (1) compare scanner performance, (2) replicate digital pathology image datasets across WSI systems, and (3) support the evaluation of clinical AI algorithms. The NPIC AI FORGE currently comprises 15 scanners from nine manufacturers. It can generate approximately 4,000 WSI images per day (approximately 7 TB of image data). This paper describes the process followed to plan and build such a facility. © 2024 The Author(s). The Journal of Pathology published by John Wiley & Sons Ltd on behalf of The Pathological Society of Great Britain and Ireland.

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Thiele, Felix, Franziska Schau, Julian M. M. Rogasch, Christoph Wetz, Stephanie Bluemel, Winfried Brenner, Holger Amthauer, Catharina Lange y Imke Schatka. "Same same but different: dopamine transporter SPECT on scanners with CZT vs. NaI detectors". EJNMMI Research 13, n.º 1 (22 de marzo de 2023). http://dx.doi.org/10.1186/s13550-023-00973-8.

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Abstract Background The aims of this study were to establish a normal database (NDB) for semiquantification of dopamine transporter (DAT) single-photon emission computed tomography (SPECT) with [123I]FP-CIT on a cadmium zinc telluride (CZT) camera, test the preexisting NaI-derived NDB for use in CZT scans, and compare the diagnostic findings in subjects imaged with a CZT scanner with either the preexisting NaI-based NDB or our newly defined CZT NDB. Methods The sample comprised 73 subjects with clinically uncertain parkinsonian syndrome (PS) who prospectively underwent [123I]FP-CIT SPECT on a CZT camera according to standard guidelines with identical acquisition and reconstruction protocols (DaTQUANT). Two experienced readers visually assessed the images and binarized the subjects into “non-neurodegenerative PS” and “neurodegenerative PS”. Twenty-five subjects from the “non-neurodegenerative PS” subgroup were randomly selected to establish a CZT NDB. The remaining 48 subjects were defined as “test group”. DaTQUANT was used to determine the specific binding ratio (SBR). For the test group, SBR values were transformed to z-scores for the putamen utilizing both the CZT NDB and the manufacturer-provided NaI-based NDB (GE NDB). A predefined fixed cut-off of -2 was used for dichotomization of z-scores to classify neurodegenerative and non-neurodegenerative PS. Performance of semiquantification using the two NDB to identify subjects with neurodegenerative PS was assessed in comparison with the visual rating. Furthermore, a randomized head-to-head comparison of both detector systems was performed semiquantitatively in a subset of 32 out of all 73 subjects. Results Compared to the visual rating as reference, semiquantification based on the dedicated CZT NDB led to fewer discordant ratings than the GE NDB in CZT scans (3 vs. 8 out of 48 subjects). This can be attributed to the putaminal z-scores being consistently higher with the GE NDB on a CZT camera (median absolute difference of 1.68), suggesting an optimal cut-off of -0.5 for the GE NDB instead of -2.0. Average binding ratios and z-scores were significantly lower in CZT compared to NaI data. Conclusions Use of a dedicated, CZT-derived NDB is recommended in [123I]FP-CIT SPECT with a CZT camera since it improves agreement between semiquantification and visual assessment.

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Schindler, Maximilian, Florian Siegerist, Tim Lange, Sophia-Marie Bach, Marianne Klawitter, Jochen Gehrig, Bernhard Ellinger, Sheraz Gul y Nicole Endlich. "FC076: Development of a High-Throughput in Vivo Drug Screening Assay Using a FSGS-Like Zebrafish Model". Nephrology Dialysis Transplantation 37, Supplement_3 (mayo de 2022). http://dx.doi.org/10.1093/ndt/gfac113.004.

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Abstract BACKGROUND AND AIMS Focal segmental sclerosis (FSGS) is a severe histopathological condition which often results in end-stage renal disease. Loss of podocytes and severe changes of podocyte foot process morphology accompanied by proteinuria are the hallmarks of FSGS. Since no therapeutic agents are available until now, further efforts must be made to identify new drugs to treat this disease. The zebrafish larva is a widely used kidney research model as the morphology and function of zebrafish and mammalian glomeruli are very similar. Since our group has already established a FSGS-like zebrafish injury model based on the nitroreductase-metronidazole cell ablation system, we have developed a high-throughput based in vivo drug screening assay. METHOD We used a zebrafish screening strain that expresses mCherry and the bacterial enzyme nitroreductase in podocytes. Additionally, a circulating vitamin-D-binding eGFP fusion protein with a size of 78 kDa is expressed and serves as a read-out for proteinuria. Incubation with 80 µM metronidazole for 24 h at 4 days post-fertilization (dpf) induces an FSGS-like phenotype in these larvae. A library of 138 epigenetic drugs were screened and the results are presented herein. Groups of 12 larvae received injury induction as well as drug treatment and were transferred individually into 96-well plates prepared with custom agarose molds. Larvae were oriented laterally and imaged with a high-content screening microscope (Acquifer Imaging Machine). The eGFP signal in the caudal vasculature as well as the glomerular mCherry signal served as readout systems. At 6 dpf, the same larvae and regions were imaged again. Custom written FIJI codes automatically segmented and measured the fluorescence intensities of both readouts and timepoints. For each larva, intensity ratios were determined and the ratios of each treatment group served as the input for statistical analysis. RESULTS Treatment for 24 hours with 80 µM metronidazole resulted in a measurable decline of the eGFP signal in the vasculature and of the podocyte mCherry signal compared to the vehicle (DMSO) group. Simultaneous treatment of metronidazole with the 138 drugs in the epigenetics library resulted in beneficial outcomes in varying degrees (9 drugs were positive, 36 compounds were lethal). CONCLUSION This new in vivo semi-automated high-throughput compatible drug screening assay allows rapid identification of FSGS protective drugs. Here we screened 138 epigenetic drugs, which led to the identification of 9 potential drugs which have had a beneficial effect on podocytes and/or the glomerular filtration barrier.

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Hosokawa, Keisuke, Yasunobu Ogawa y Satoshi Taguchi. "Imaging of polar cap patches with a low-cost airglow camera: pilot observations in Svalbard, Norway". Earth, Planets and Space 71, n.º 1 (7 de noviembre de 2019). http://dx.doi.org/10.1186/s40623-019-1094-7.

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Abstract We evaluate the capability of a low-cost all-sky imager (ASI), which has been operative in Longyearbyen (78.1° N, 15.5° E), Norway, to detect 630.0 nm airglow signatures of polar cap patches. The ASI is composed of a small camera, with a charge-coupled device (CCD), manufactured by Watec Co. Ltd., a fish-eye lens, and an optical filter whose central wavelength is 632.0 nm and full-width half maximum (FWHM) is 10 nm. In Longyearbyen, another ASI equipped with a cooled electron-multiplying charge-coupled device (EMCCD) camera has been operative for observations of polar cap patches. We compare the images from the two systems and investigate the performance of the low-cost ASI. On the night of December 4, 2013, a series of polar cap patches were observed by the EMCCD ASI. The low-cost ASI also detected regions of enhanced 630.0 nm airglow passing through the fields-of-view. The quality of the raw images from the low-cost ASI obtained every 4 s were visibly much worse than that of the EMCCD ASI. However, an integration of 7–15 consecutive images made it possible to capture the temporal evolution and spatial structure of the patches, for example, their anti-sunward propagation and finger-like structures along the trailing edge. The estimated values of the absolute optical intensity from the low-cost ASI were found to be consistent with those from the EMCCD ASI, whereby the offset was < 100 R. This offset can be explained by the contribution of the background continuum emission to the low-cost ASI images, because the band width of the optical filter used for the low-cost ASI is ~ 3 times wider than that used for the EMCCD ASI. The results indicate that the airglow measurement with the low-cost ASI is feasible even for quantitative studies of F-region phenomena such as the dynamics of polar cap patches.

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Bormann, C., M. Kanakasabapathy, P. Thirumalaraju, I. Dimitriadis, I. Souter, K. Hammer y H. Shafiee. "O-125 Development of an artificial intelligence embryo witnessing system to accurately track and identify patient specific embryos in a human IVF laboratory". Human Reproduction 36, Supplement_1 (1 de julio de 2021). http://dx.doi.org/10.1093/humrep/deab126.050.

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Abstract Study question Can convolutional neural networks (CNN) be used as a witnessing system to accurately track and identify patient specific embryos at the cleavage stage of development? Summary answer We developed the first artificial intelligence driven witnessing system to accurately track cleavage and blastocyst stage embryos in a human ART laboratory. What is known already There are reports of human errors in embryo tracking that have led to the births of children with different genetic makeup than their birth parents. Clinical practices rely on manual identification, barcodes or radio-frequency identification technology to track embryos. These systems are designed to track culture dishes but are unable to monitor developing embryos within the dish to help ensure an error-free patient match. Previously, we developed an AI witnessing system to track blastocysts with 100% accuracy. The goal of this study was to determine whether an AI witnessing system could be developed that accurately tracks cleavage stage embryos. Study design, size, duration A pre-developed deep neural network technology was first trained and tested on 4944 embryos images. The algorithm processed embryo images for each patient and produced a unique key that was associated with the patient ID at 60 hpi, which formed our library. When the algorithm evaluated embryos at 64 hpi it generated another key that was matched with the patient’s unique key available in the library. Participants/materials, setting, methods A total of 3068 embryos from 412 patients were examined by the CNN at both 60 hpi and 64 hpi. These timepoints were chosen as they reflect the time our laboratory evaluates Day 3 embryos (60 hpi) and the time we move them to another dish and prepare them for transfer (64 hpi). The patient cohorts ranged from 3-12 embryos per patient. Main results and the role of chance The accuracy of the CNN in correctly matching the patient identification with the patient embryo cohort was 100% (CI: 99.1% to 100.0%, n = 412). Limitations, reasons for caution Limitations of this study include that all embryos were imaged under identical conditions and within the same EmbryoScope. Additionally, this study only examined fresh Day 3 embryos cultured over a span of 4 hours. Future studies should include images of fresh and frozen/thawed embryos captured using different imaging systems. Wider implications of the findings This study describes the first artificial intelligence-based approach for cleavage stage embryo tracking and patient specimen identification in the IVF laboratory. This technology offers a robust witnessing step based on unique morphological features that are specific to each individual embryo. Trial registration number This work was partially supported by the Brigham Precision Medicine Developmental Award (Brigham Precision Medicine Program, Brigham and Women’s Hospital), Partners Innovation Discovery Grant (Partners Healthcare), and R01AI118502, and R01AI138800.

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Hoppe, Ulrich, Goetz Brademann, Timo Stöver, Angel Ramos de Miguel, Robert Cowan, Manuel Manrique, Juan Carlos Falcón-González et al. "Evaluation of a Transimpedance Matrix Algorithm to Detect Anomalous Cochlear Implant Electrode Position". Audiology and Neurotology, 18 de marzo de 2022, 1–9. http://dx.doi.org/10.1159/000523784.

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Introduction: Transimpedance measurements from cochlear implant electrodes have the potential to identify anomalous electrode array placement, such as tip fold-over (TFO) or fold-back, basal electrode kinking, or buckling. Analysing transimpedance may thus replace intraoperative or post-operative radiological imaging to detect any potential misplacements. A transimpedance algorithm was previously developed to detect deviations from a normal electrode position with the aim of intraoperatively detecting TFO. The algorithm had been calibrated on 35 forced, tip folded electrode arrays in six temporal bones to determine the threshold criterion required to achieve a sensitivity of 100%. Our primary objective here was to estimate the specificity of this TFO algorithm in patients, in a prospective study, for a series of electrode arrays shown to be normally inserted by post-operative imaging. Methods: Intracochlear voltages were intraoperatively recorded for 157 ears, using Cochlear’s Custom Sound™ EP 5 electrophysiological software (Cochlear Ltd., Sydney, NSW, Australia), for both Nucleus® CI512 and CI532 electrode arrays. The algorithm analysed the recorded 22 × 22 transimpedance matrix (TIM) and results were displayed as a heatmap intraoperatively, only visible to the technician in the operating theatre. After all clinical data were collected, the algorithm was evaluated on the bench. The algorithm measures the transimpedance gradients and corresponding phase angles (θ) throughout the TIM and calculates the gradient phase range. If this was greater than the predetermined threshold, the algorithm classified the electrode array insertion as having a TFO. Results: Five ears had no intraoperative TIM and four anomalous matrices were identified from heatmaps and removed from the specificity analysis. Using the 148 remaining data sets (n = 103 CI532 and n = 45 CI512), the algorithm had an average specificity of 98.6% (95.80%–99.75%). Conclusion: The algorithm was found to be an effective screening tool for the identification of TFOs. Its specificity was within acceptable levels and resulted in a positive predictive value of 76%, with an estimated incidence of fold-over of 4% in perimodiolar arrays. This would mean 3 out of 4 cases flagged as a fold-over would be correctly identified by the algorithm, with the other being a false positive. The measurements were applied easily in theatre allowing it to be used as a routine clinical tool for confirming correct electrode placement.

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Carles, Montserrat, Tobias Fechter, Luis Martí-Bonmatí, Dimos Baltas y Michael Mix. "Experimental phantom evaluation to identify robust positron emission tomography (PET) radiomic features". EJNMMI Physics 8, n.º 1 (12 de junio de 2021). http://dx.doi.org/10.1186/s40658-021-00390-7.

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Abstract Background Radiomics analysis usually involves, especially in multicenter and large hospital studies, different imaging protocols for acquisition, reconstruction, and processing of data. Differences in protocols can lead to differences in the quantification of the biomarker distribution, leading to radiomic feature variability. The aim of our study was to identify those radiomic features robust to the different degrading factors in positron emission tomography (PET) studies. We proposed the use of the standardized measurements of the European Association Research Ltd. (EARL) accreditation to retrospectively identify the radiomic features having low variability to the different systems and reconstruction protocols. In addition, we presented a reproducible procedure to identify PET radiomic features robust to PET/CT imaging metal artifacts. In 27 heterogeneous homemade phantoms for which ground truth was accurately defined by CT segmentation, we evaluated the segmentation accuracy and radiomic feature reliability given by the contrast-oriented algorithm (COA) and the 40% threshold PET segmentation. In the comparison of two data sets, robustness was defined by Wilcoxon rank tests, bias was quantified by Bland–Altman (BA) plot analysis, and strong correlations were identified by Spearman correlation test (r > 0.8 and p satisfied multiple test Bonferroni correction). Results Forty-eight radiomic features were robust to system, 22 to resolution, 102 to metal artifacts, and 42 to different PET segmentation tools. Overall, only 4 radiomic features were simultaneously robust to all degrading factors. Although both segmentation approaches significantly underestimated the volume with respect to the ground truth, with relative deviations of −62 ± 36% for COA and −50 ± 44% for 40%, radiomic features derived from the ground truth were strongly correlated and/or robust to 98 radiomic features derived from COA and to 102 from 40%. Conclusion In multicenter studies, we recommend the analysis of EARL accreditation measurements in order to retrospectively identify the robust PET radiomic features. Furthermore, 4 radiomic features (area under the curve of the cumulative SUV volume histogram, skewness, kurtosis, and gray-level variance derived from GLRLM after application of an equal probability quantization algorithm on the voxels within lesion) were robust to all degrading factors. In addition, the feasibility of 40% and COA segmentations for their use in radiomics analysis has been demonstrated.

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Krokos, Georgios, Lucy C. Pike, Gary J. R. Cook y Paul K. Marsden. "Standardisation of conventional and advanced iterative reconstruction methods for Gallium-68 multi-centre PET-CT trials". EJNMMI Physics 8, n.º 1 (17 de julio de 2021). http://dx.doi.org/10.1186/s40658-021-00400-8.

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Abstract Purpose To assess the applicability of the Fluorine-18 performance specifications defined by EANM Research Ltd (EARL), in Gallium-68 multi-centre PET-CT trials using conventional (ordered subset expectation maximisation, OSEM) and advanced iterative reconstructions which include the systems’ point spread function (PSF) and a Bayesian penalised likelihood algorithm (BPL) commercially known as Q.CLEAR. The possibility of standardising the two advanced reconstruction methods was examined. Methods The NEMA image quality phantom was filled with Gallium-68 and scanned on a GE PET-CT system. PSF and BPL with varying post-reconstruction Gaussian filter width (2–6.4 mm) and penalisation factor (200–1200), respectively, were applied. The average peak-to-valley ratio from six profiles across each sphere was estimated to inspect any edge artefacts. Image noise was assessed using background variability and image roughness. Six GE and Siemens PET-CT scanners provided Gallium-68 images of the NEMA phantom using both conventional and advanced reconstructions from which the maximum, mean and peak recoveries were drawn. Fourteen patients underwent 68Ga-PSMA PET-CT imaging. BPL (200-1200) reconstructions of the data were compared against PSF smoothed with a 6.4-mm Gaussian filter. Results A Gaussian filter width of approximately 6 mm for PSF and a penalisation factor of 800 for BPL were needed to suppress the edge artefacts. In addition, those reconstructions provided the closest agreement between the two advanced iterative reconstructions and low noise levels with the background variability and the image roughness being lower than 7.5% and 11.5%, respectively. The recoveries for all methods generally performed at the lower limits of the EARL specifications, especially for the 13- and 10-mm spheres for which up to 27% (conventional) and 41% (advanced reconstructions) lower limits are suggested. The lesion standardised uptake values from the clinical data were significantly different between BPL and PSF smoothed with a Gaussian filter of 6.4 mm wide for all penalisation factors except for 800 and 1000. Conclusion It is possible to standardise the advanced reconstruction methods with the reconstruction parameters being also sufficient for minimising the edge artefacts and noise in the images. For both conventional and advanced reconstructions, Gallium-68 specific recovery coefficient limits were required, especially for the smallest phantom spheres.

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