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Poulsen, Carsten. "Development of a positioning system for 3D ultrasound." Link to electronic thesis, 2005. http://www.wpi.edu/Pubs/ETD/Available/etd-101805-180813/.
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Ross, Erin. "Freehand three dimensional ultrasound for imaging components of the musculoskeletal system." Thesis, University of Edinburgh, 2010. http://hdl.handle.net/1842/4500.
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There have been reports on the use of Ultrasound (US) for monitoring fracture repair and for measuring muscle volume. Change in muscle mass is a useful bio-marker for monitoring the use and disuse of muscle, and the affects of age, disease and injury. The main modality for imaging bone is X-ray and for muscle volume Magnetic Resonance (MR). Previous studies have shown US to have advantages over X-ray and MR. US can image all stages of the fracture repair process and can detect signs of healing 4-6 weeks before X-ray allowing earlier detection of possible complications. Compared to MR, US is less resource intensive, easier to access and also has fewer exclusion criteria for patients. Despite these advantages, the limited field of view that US can provide results in high operator dependency for scan interpretation and also for length and volume measurements. Three-dimensional Ultrasound (3D US) has been developed to overcome these limitations and has been used to provide extended field of view images of the foetus and the heart and to obtain accurate volume measurements for organs. In this thesis it is hypothesized that 3D US can provide a more comprehensive method of imaging fracture repair than X-ray and is also a viable alternative to MR for determining muscle volumes in vivo. Initially, an electromagnetically (EM) tracked 3D US system was evaluated for clinical use using phantom-based experiments. It was found that the presence of metal objects in or near the EM field caused distortion and resulted in errors in the volume measurements of phantoms of up to ±20%. An optically tracked system was also evaluated and it was found that length measurements of a phantom could be made to within ±1.3%. Fracture repair was monitored in five patients with lower limb fractures. Signs of healing were visible earlier on 3D US with a notable, although variable, lag between callus development on X-ray compared to 3D US. 3D US provided a clearer view of callus formation and the changes in density of the callus as it matured. Additional information gained by applying image processing methods to the 3D US data was used to develop a measure of callus density and to identify the frequency dependent appearance of the callus. Volume measurements of the rectus femoris quadricep muscle were obtained using 3DUS from eleven healthy volunteers and were validated against volume measurements derived using MR. The mean difference between muscle volume measurements obtained using 3D US and MR was 0.53 cm3 with a standard deviation of 1.09 cm3 and 95% confidence intervals of 0.20 - 1.27 cm3 In conclusion, 3D US demonstrates great potential as a tool for imaging components of the musculoskeletal system and as means of measuring callus density.
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Goldsmith, Abraham Myron. "An inertial-optical tracking system for quantitative, freehand, 3D ultrasound." Worcester, Mass. Worcester Polytechnic Institute, 2008. http://www.wpi.edu/Pubs/ETD/Available/etd-011609-133509/.
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Sherebrin, Shi. "A freehand three-dimensional ultrasound system, application to imaging the carotid arteries." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk2/tape16/PQDD_0010/MQ28660.pdf.
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Jong, Jing-Ming. "Organ volume estimation from magnetic sensor based 3D ultrasound data : application in gastric emptying /." Thesis, Connect to this title online; UW restricted, 1997. http://hdl.handle.net/1773/6003.
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Edwards, Warren S. "A low-cost high-performance three-dimensional ultrasound system and its clinical application in obstetrics /." Thesis, Connect to this title online; UW restricted, 1999. http://hdl.handle.net/1773/5906.
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Goldsmith, Abraham Myron. "An Inertial-Optical Tracking System for Quantitative, Freehand, 3D Ultrasound." Digital WPI, 2009. https://digitalcommons.wpi.edu/etd-theses/107.
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Three dimensional (3D) ultrasound has become an increasingly popular medical imaging tool over the last decade. It offers significant advantages over Two Dimensional (2D) ultrasound, such as improved accuracy, the ability to display image planes that are physically impossible with 2D ultrasound, and reduced dependence on the skill of the sonographer. Among 3D medical imaging techniques, ultrasound is the only one portable enough to be used by first responders, on the battlefield, and in rural areas. There are three basic methods of acquiring 3D ultrasound images. In the first method, a 2D array transducer is used to capture a 3D volume directly, using electronic beam steering. This method is mainly used for echocardiography. In the second method, a linear array transducer is mechanically actuated, giving a slower and less expensive alternative to the 2D array. The third method uses a linear array transducer that is moved by hand. This method is known as freehand 3D ultrasound. Whether using a 2D array or a mechanically actuated linear array transducer, the position and orientation of each image is known ahead of time. This is not the case for freehand scanning. To reconstruct a 3D volume from a series of 2D ultrasound images, assumptions must be made about the position and orientation of each image, or a mechanism for detecting the position and orientation of each image must be employed. The most widely used method for freehand 3D imaging relies on the assumption that the probe moves along a straight path with constant orientation and speed. This method requires considerable skill on the part of the sonographer. Another technique uses features within the images themselves to form an estimate of each image's relative location. However, these techniques are not well accepted for diagnostic use because they are not always reliable. The final method for acquiring position and orientation information is to use a six Degree-of-Freedom (6 DoF) tracking system. Commercially available 6 DoF tracking systems use magnetic fields, ultrasonic ranging, or optical tracking to measure the position and orientation of a target. Although accurate, all of these systems have fundamental limitations in that they are relatively expensive and they all require sensors or transmitters to be placed in fixed locations to provide a fixed frame of reference. The goal of the work presented here is to create a probe tracking system for freehand 3D ultrasound that does not rely on any fixed frame of reference. This system tracks the ultrasound probe using only sensors integrated into the probe itself. The advantages of such a system are that it requires no setup before it can be used, it is more portable because no extra equipment is required, it is immune from environmental interference, and it is less expensive than external tracking systems. An ideal tracking system for freehand 3D ultrasound would track in all 6 DoF. However, current sensor technology limits this system to five. Linear transducer motion along the skin surface is tracked optically and transducer orientation is tracked using MEMS gyroscopes. An optical tracking system was developed around an optical mouse sensor to provide linear position information by tracking the skin surface. Two versions were evaluated. One included an optical fiber bundle and the other did not. The purpose of the optical fiber is to allow the system to integrate more easily into existing probes by allowing the sensor and electronics to be mounted away from the scanning end of the probe. Each version was optimized to track features on the skin surface while providing adequate Depth Of Field (DOF) to accept variation in the height of the skin surface. Orientation information is acquired using a 3 axis MEMS gyroscope. The sensor was thoroughly characterized to quantify performance in terms of accuracy and drift. This data provided a basis for estimating the achievable 3D reconstruction accuracy of the complete system. Electrical and mechanical components were designed to attach the sensor to the ultrasound probe in such a way as to simulate its being embedded in the probe itself. An embedded system was developed to perform the processing necessary to translate the sensor data into probe position and orientation estimates in real time. The system utilizes a Microblaze soft core microprocessor and a set of peripheral devices implemented in a Xilinx Spartan 3E field programmable gate array. The Xilinx Microkernel real time operating system performs essential system management tasks and provides a stable software platform for implementation of the inertial tracking algorithm. Stradwin 3D ultrasound software was used to provide a user interface and perform the actual 3D volume reconstruction. Stradwin retrieves 2D ultrasound images from the Terason t3000 portable ultrasound system and communicates with the tracking system to gather position and orientation data. The 3D reconstruction is generated and displayed on the screen of the PC in real time. Stradwin also provides essential system features such as storage and retrieval of data, 3D data interaction, reslicing, manual 3D segmentation, and volume calculation for segmented regions. The 3D reconstruction performance of the system was evaluated by freehand scanning a cylindrical inclusion in a CIRS model 044 ultrasound phantom. Five different motion profiles were used and each profile was repeated 10 times. This entire test regimen was performed twice, once with the optical tracking system using the optical fiber bundle, and once with the optical tracking system without the optical fiber bundle. 3D reconstructions were performed with and without the position and orientation data to provide a basis for comparison. Volume error and surface error were used as the performance metrics. Volume error ranged from 1.3% to 5.3% with tracking information versus 15.6% to 21.9% without for the version of the system without the optical fiber bundle. Volume error ranged from 3.7% to 7.6% with tracking information versus 8.7% to 13.7% without for the version of the system with the optical fiber bundle. Surface error ranged from 0.319 mm RMS to 0.462 mm RMS with tracking information versus 0.678 mm RMS to 1.261 mm RMS without for the version of the system without the optical fiber bundle. Surface error ranged from 0.326 mm RMS to 0.774 mm RMS with tracking information versus 0.538 mm RMS to 1.657 mm RMS without for the version of the system with the optical fiber bundle. The prototype tracking system successfully demonstrated that accurate 3D ultrasound volumes can be generated from 2D freehand data using only sensors integrated into the ultrasound probe. One serious shortcoming of this system is that it only tracks 5 of the 6 degrees of freedom required to perform complete 3D reconstructions. The optical system provides information about linear movement but because it tracks a surface, it cannot measure vertical displacement. Overcoming this limitation is the most obvious candidate for future research using this system. The overall tracking platform, meaning the embedded tracking computer and the PC software, developed and integrated in this work, is ready to take advantage of vertical displacement data, should a method be developed for sensing it.
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Pagoulatos, Nikolaos. "Algorithms and systems for registration of two-dimensional and three-dimensional ultrasound images /." Thesis, Connect to this title online; UW restricted, 2002. http://hdl.handle.net/1773/6035.
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Inglis, Scott. "Development of a freehand three-dimensional radial endoscopic ultrasonography system." Thesis, University of Edinburgh, 2009. http://hdl.handle.net/1842/4287.
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Oesophageal cancer is an aggressive malignancy with an overall five-year survival of 5-10% and two-thirds of patients have irresectable disease at diagnosis. Accurate staging of oesophageal cancer is important as survival closely correlates with the stage of the tumour, nodal involvement and presence of metastases (TNM staging). Endoscopic ultrasonography (EUS) is currently the most reliable modality for providing accurate T and N staging. Depending on findings of the staging, various treatment options including endoscopic, oncological, and surgical treatments may be performed. It was theorised that the development of three-dimensional radial endoscopic ultrasonography would reduce the operator dependence of EUS and provide accurate dimensional and volume measurements to aid planning and monitoring of treatment. This thesis investigates the development of a three dimensional endoscopic ultrasound technique that can be used with the radial echoendoscopes. Various agar-based tissue mimicking material (TMM) recipes were characterised using a scanning acoustic macroscope to obtain the acoustic properties of attenuation, backscatter and speed of sound. Using these results, a number of endoscopic ultrasound phantoms were developed for the in-vitro investigation and evaluation of 3D-EUS techniques. To increase my understanding of EUS equipment, the imaging and acoustic properties of the EUS endoscopes were characterised using a pipe phantom and a hydrophone. The dual ‘single element’ mechanical and ‘multi-element’ electronic echoendoscopes were investigated. Measured imaging properties included dead space, low contrast penetration, and pipe length. The measured acoustic properties included transmitted beam plots, active working frequency and peak pressures. Three-dimensional ultrasound techniques were developed for specific application to EUS. This included the study of positional monitoring systems, reconstruction algorithms and measurement techniques. A 3D-EUS system was developed using a Microscribe positional arm and frame grabber card, to acquire the 3D dataset. A Matlab 3D-EUS toolbox was written to reconstruct and analyse the volumes. The 3D-EUS systems were evaluated on the EUS phantom and in clinical cases. The usefulness of the 3D-EUS systems was evaluated in a cohort of patients, who were routinely investigated by conventional EUS for a variety of upper gastrointestinal pathology. 3D-EUS accurately staged early tumours and provided the necessary anatomical information to facilitate treatment. With regards to more advanced tumours, 3D-EUS was more accurate than EUS in T and N staging. 3D-EUS gave useful anatomical details in a variety of benign conditions such as varicies and GISTs.
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John, Babbin S. "Validation of three-dimensional ultrasound in the imaging of the renal pelvi-calyceal system and investigation of the use of four- dimensional ultrasound in renal percutaneous intervention." Thesis, St George's, University of London, 2016. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.703120.
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Standard two-dimensional (20) ultrasound is widely utilised in diagnosis and intervention in urinary tract stone disease. 20 ultrasound as an interventional tool is limited to the well dilated renal pelvi-calyceal system. Three-dimensional (3~) and real-time (four-dimensional, 40) ultrasound has had minimal utility so far in the imaging of the renal pelvi-calyceal system and percutaneous intervention. The use of ultrasound technology also needs to be expanded to minimise radiation exposure to patients. The aim of this thesis is to explore the radiation exposure to patients in a stone episode and the application of three-dimensional ultrasound in the imaging of the renal pelvi-calyceal system (PCS). It also looks at the utility of 40 ultrasound for access in to less-dilated pelvi-calyceal systems, with the help of a dedicated model. Cumulative radiation exposure to patients undergoing stone investigation and treatment was assessed. We utilised an anthropomorphic renal model to perform measurements of the renal PCS using 20 and 3D ultrasound in order to validate 3D ultrasound use in the complex anatomy of the kidney. 40 ultrasound was investigated as a guidance tool in renal percutaneous intervention by building a dedicated interventional model and assessing accuracy of 40 ultrasound guided punctures with the help of fluoroscopy. Patients undergoing urinary tract stone diagnosis and treatment were exposed an average of 5.3 miliiSieverts (mSv) of radiation but could be as high 14.4 mSv. 30 ultrasound was found to be more accurate in assessing the renal PCS compared to 20 ultrasound. 40 ultrasound punctures were accurate and helped better placement of guidewires but overall accuracy was equivalent to 20 and some limitations were also seen. Radiation exposure to stone patients is a significant problem and imaging modalities like ultrasound need to be utilised more. 30 ultrasound proved accurate in the assessment of the complex anatomy of the PCS and showed promise as a guidance tool in intervention. However, some limitations were seen and technology advancements are awaited.
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Tierney, Rebecca Louise. "3D ultrasound imaging to quantify kidney motion due to respiration." Thesis, Queensland University of Technology, 2000.
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Hacihaliloglu, Ilker. "Towards a novel minimally invasive three dimensional ultrasound imaging based computer assisted orthopaedic surgery system for bone fracture reduction." Thesis, University of British Columbia, 2010. http://hdl.handle.net/2429/24463.
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Current practice in orthopaedic surgery relies on intra-operative two dimensional (2D) fluoroscopy as the main imaging modality for localization and visualization of bone tissue, fractures, implants, and surgical tool positions. However, with such projection imaging, surgeons typically face considerable difficulties in accurately localizing bone fragments in three dimensional (3D) space and assessing the adequacy and accuracy of reduced fractures. Furthermore, fluoroscopy involves significant radiation exposure. Ultrasound (US) has recently emerged as a potential non-ionizing imaging alternative that promises safer operation while remaining relatively cheap and widely available. US image data, however, is typically characterized by high levels of speckle noise, reverberation, anisotropy and signal dropout which introduce significant difficulties in interpretation of captured data, automatic detection and segmentation of image features and accurate localization of imaged bone surfaces.
In this thesis we propose a novel technique for automatic bone surface and surgical tool localization in US that employs local phase image information to derive symmetry-based features corresponding to tissue/bone or tissue/surgical tool interfaces through the use of 2D Log-Gabor filters. We extend the proposed method to 3D in order to take advantage of correlations between adjacent images. We validate the performance of the proposed approach quantitatively using realistic phantom and in-vitro experiments as well as qualitatively on in-vivo and ex-vivo data. Furthermore, we evaluate the ability of the proposed method in detecting gaps between fractured bone fragments. The current study is therefore the first to show that bone surfaces, surgical tools and fractures can be accurately localized using local phase features computed directly from 3D ultrasound image volumes.
Log-Gabor filters have a strong dependence on the chosen filter parameters, the values of which significantly affect the outcome of the features being extracted. We present a novel method for contextual parameter selection that is autonomously adaptive to image content. Finally, we investigate the hypothesis that 3D US can be used to detect fractures reliably in the emergency room with three clinical studies. We believe that the results presented in this work will be invaluable for all future imaging studies with US in orthopaedics.
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Icenogle, David A. "Development of virtual mitral valve leaflet models from three-dimensional echocardiography." Thesis, Georgia Institute of Technology, 2012. http://hdl.handle.net/1853/48994.
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Mitral valve (MV) disease is responsible for approximately 2,581 deaths and 41,000 hospital discharges each year in the US. Mitral regurgitation (MR), retrograde blood from through the MV, is often an indicator of MV disease. Surgical repair of MVs is preferred over replacement, as it is correlated with better patient quality of life. However, replacement rates are still near 40% because MV surgical repair expertise is not spread across all hospitals. In addition, 15-80% of surgical repair patients have recurrent MR within 10 years. Quantitative patient-specific models could aid these issues by providing less experienced surgeons with additional information before surgery and a quantitative map of patient valve changes after surgery. Real-time 3D echocardiography (RT3DE) can provide high quality 3D images of MVs and has been used to generate quantitative models previously. However, there is not currently an efficient, dynamic, and validated method that is fast enough to use in common practice. To fill this need, a tool to generate quantitative 3D models of mitral valve leaflets from RT3DE in an efficient manner was created. Then an in vitro echocardiography correction scheme was devised and a dynamic, in vitro validation of the tool was performed. The tool demonstrated that it could generate dynamic, complex MV geometry accurately and more efficiently than current methods available. In addition, the ability for mesh interpolation techniques to reduce segmentation time was demonstrated. The tool generated by this study provides a method to quickly and accurately generate MV geometry that could be applied to dynamic patient specific geometry to aid surgical decisions and track patient geometry changes after surgery.
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Abeysekera, Jeffrey Michael. "Three dimensional ultrasound elasticity imaging." Thesis, University of British Columbia, 2016. http://hdl.handle.net/2429/57462.
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Changes in tissue elasticity are correlated with certain pathological changes, such as localized stiffening of malignant tumours or diffuse stiffening of liver fibrosis or placenta dysfunction. Elastography is a field of medical imaging that characterizes the mechanical properties of tissue, such as elasticity and viscosity. The elastography process involves deforming the tissue, measuring the tissue motion using an imaging technique such as ultrasound or magnetic resonance imaging (MRI), and solving the equations of motion. Ultrasound is well suited for elastography, however, it presents challenges such as anisotropic measurement accuracy and providing two dimensional (2D) measurements rather than three dimensional (3D). This thesis focuses on overcoming some of these limitations by improving upon methods of imaging absolute elasticity using 3D ultrasound. In this thesis, techniques are developed for 3D ultrasound acquired from transducers fitted with a motor to sweep the image plane, however many of the techniques can be applied to other forms of 3D acquisition such as matrix arrays. First, a flexible framework for 3D ultrasound elastography system is developed. The system allows for comparison and in depth analysis of errors in current state of the art 3D ultrasound shear wave absolute vibro-elastography (SWAVE). The SWAVE system is then used to measure the viscoelastic properties of placentas, which could be clinically valuable in diagnosing preeclampsia and fetal growth restriction. A novel 3D ultrasound calibration technique is developed which estimates the transducer motor parameters for accurate determination of location and orientation of every data sample, as well as for enabling position tracking of a 3D ultrasound transducer so multiple volumes can be combined. Another calibration technique using assumed motor parameters is developed, and an improvement to an existing N-wire method is presented. The SWAVE research system is extended to measure shear wave motion vectors with a new acquisition scheme to create synchronous volumes of ultrasound data. Regularization based on tissue incompressibility is used to reduce noise in the motion measurements. Lastly, multiple ultrasound volumes from different angles are combined for measurement of the full motion vector, and demonstrating accurate reconstructions of elasticity are feasible using the techniques developed in this thesis.Applied Science, Faculty of
Mechanical Engineering, Department of
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Hsu, P. W. "Freehand three- dimensional ultrasound calibration." Thesis, University of Cambridge, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.604687.
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In this thesis, we investigate how to achieve an accurate reliable and rapid probe calibration. Our first step is to improve the reliability of an accurate calibration technique from the literature. The Cambridge phantom, a variant of plane-based calibration, has been shown to be one of the most accurate calibration techniques. Unfortunately, calibrations performed using plane-based techniques are often unreliable. We show how it is possible to provide feedback on the reliability of the calibration. This allows the user to rectify an unreliable calibration. Having achieved an accurate and reliable calibration, we now search for a fast and easy calibration technique. We study a class of two-dimensional alignment phantoms – the Z-fiducial phantom. Probe calibration using such a phantom only requires a single image of the phantom. However, calibration speed using this phantom is impeded by the necessity of segmenting isolated points on the phantom reliably, which requires human intervention. We solve this problem by mounting a thin rubber membrane on top of the phantom. The membrane is segmented automatically and the phantom features can be easily located. This enables us to segment isolated points automatically at the full PAL frame rate of 25Hz, enabling calibration to be completed in a few seconds. In addition, to improve the existing calibration techniques, we present two novel phantoms – the cone phantom and the Cambridge stylus. They are both simple in design, easy to use and produce accurate calibrations. The cone phantom produces calibrations with accuracies matching the Cambridge phantom. The Cambridge stylus is small in size and can be carried around conveniently. These phantoms offer alternatives to the Cambridge phantom and the Z-phantom, ensuring calibration reliability and simplicity, while producing accurate calibrations.
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Gomersall, William Henry. "Deconvolution of three-dimensional medical ultrasound." Thesis, University of Cambridge, 2011. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.609431.
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Tong, Shidong. "Three-dimensional ultrasound imaging of the prostate." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp04/nq28526.pdf.
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Syn, Michael Hsien-Min. "Model-based three-dimensional freehand ultrasound imaging." Thesis, University of Cambridge, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.627596.
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Al-Mejrad, Ali Saleh Khalid. "Medical ultrasound : a study of real-time three dimensional ultrasound imaging." Thesis, University of Edinburgh, 1996. http://hdl.handle.net/1842/21190.
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Ultrasonic techniques are very widely applied in medicine. Real-time two dimensional imaging is a technology which is extremely well-suited to medical applications since it enables moving structures to be observed and rapid searching through tissue structures to be performed. Three-dimensional (3D) ultrasonic imaging techniques have been developed but to date there has been very limited success in the development of real-time versions. The aim of this thesis is to study the feasibility of real-time 3D ultrasonic imaging to see if ways can be found to overcome the fundamental problem of sparcity of echo line data when a volume is scanned in real-time. The fundamental problem arises because conventional ultrasonic scanners have an upper limit of rate of generation of scan lines of around 10 KHz. The number of scan lines in each scanned volume is therefore low e.g. 2000 for a volume scan rate of 5 volumes per second. The aim of this thesis is to investigate whether or not modern electronic and image processing techniques can overcome this fundamental problem. During the first phase of our study, a microcomputer based C-scan test-rig system including hardware and software has been constructed to investigate the effectiveness of real-time image processing in compensating for the fundamental sparcity of echo data. This was investigated initially since C-scans suffer from the same sparcity of echo data as 3D scans. After the promising results obtained from this system using a number of image processing techniques, a hand-held 3D ultrasound system including hardware and software based on one of the commercial scanners (Dynamic Imaging C2000) has been constructed to extend our study to 3D. A number of test objects in addition to volunteers were scanned to investigate the feasibility of real-time 3D ultrasound imaging. Finally, a specification for real-time ultrasound imaging is discussed.
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Roelfsema, Nanette Marianne. "Three-dimensional ultrasound study of fetal craniofacial anatomy." [S.l.] : Rotterdam : [The Author] ; Erasmus University [Host], 2007. http://hdl.handle.net/1765/10625.
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Hughes, Stephen William. "Measurement of organ volume using three dimensional ultrasound." Thesis, Imperial College London, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.484233.
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Hughes, Stephen W. "Measurement of organ volume using three dimensional ultrasound." Thesis, King's College London, 1997. https://eprints.qut.edu.au/16892/1/16892.pdf.
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A system has been developed for calculating volume from a sequence of multiplanar two dimensional ultrasound images. Ultrasound image capture is via a video digitising card installed in a personal computer. Regions of interest are transformed from 2D image space to 3D space using position and orientation data obtained from an electromagnetic device (Fastrak, Polhemus Inc, VT) attached to the ultrasound probe. The accuracy of the system was assessed by scanning 10 water filled balloons (13 - 141 ml), 10 kidneys (147 - 200 ml) and 16 fetal livers (8 - 37 ml) immersed in water using an Acuson 128XP/10 (5 MHz curvilinear probe). Volume was calculated using the ellipsoid and planimetry methods, two tetrahedral methods, and two integral methods - a ray tracing algorithm and one based on Gauss’ theorem. Actual volume was estimated by weighing (balloons) and water displacement (kidneys and livers). The mean percentage error (± one standard deviation) for the ray tracing algorithm was 0.9 ± 2.4%, 2.7 ± 2.3%, 6.6 ± 5.4% for balloons, kidneys and livers respectively. Four sets of 10 kidneys were scanned using three scan techniques on four different ultrasound machines of varying image quality. There was no significant difference between scan techniques or machines. Twelve of the 16 fetal livers were scanned by computed tomography and magnetic resonance. The mean percentage errors were 5.3 ± 4.7%, -3.1 ± 9.6%, -0.03 ± 9.7 for ultrasound (radial scans, ray volumes), magnetic resonance and X-ray computed tomography (voxel counting) respectively. Tests carried out on the Fastrak showed that it is suitable for use in a clinical environment if care is exercised. These in vitro studies suggest that the system has the potential to be a useful tool in measuring organ volume in vivo.
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Barratt, Dean Colin. "Quantification of carotid artery disease using three dimensional ultrasound imaging." Thesis, Imperial College London, 2002. http://hdl.handle.net/10044/1/8563.
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Lowe, Christopher. "Three-dimensional ultrasound in the management of abdominal aortic aneurysm." Thesis, University of Manchester, 2016. https://www.research.manchester.ac.uk/portal/en/theses/threedimensional-ultrasound-in-themanagement-of-abdominal-aorticaneurysm(b8950db7-847b-4d11-a6a5-2a06b3bb66d0).html.
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Objectives: Clinical implementation of 3D ultrasound (3D-US) in vascular surgery is in its infancy. The aim of this thesis was to develop novel clinical applications for 3D-US in the diagnosis and management of abdominal aortic aneurysm (AAA). Methods: Four principle clinical applications were investigated. 1) Intraoperative imaging – The ability of 3D-US to detect and classify endoleaks was compared with digital subtraction angiography in patients undergoing EVAR. 2) Detection and classification of endoleaks following endovascular aneurysm repair (EVAR) – The abilityof 3D-US to accurately detect and classify endoleaks following EVAR was compared to CTA and the final multi-disciplinary team decision. 3) AAA volume measurement – measurements using magnetic and optically-tracked 3D-US were compared to CTA. 4) Biomechanical analysis – the challenges of using 3D-US to generate surface models for biomechanical simulation was explored by development of an interactive segmentation technique and comparison of paired CT and 3D-US datasets. Optimal results were used in finite element analysis (FEA) and computational fluid dynamic(CFD) simulations. Results: 3D-US out-performed uniplanar angiography for the detection of endoleaks during EVAR. This approach allowed contrast-free EVAR to be performed in patients with poor renal function. 3D contrast-enhanced ultrasound was superior to CTA for endoleak detection and classification when compared with the final decision of the multi-disciplinary team. Optimal results for AAA volume measurements were gained using an optically tracked 3D-US system in EVAR surveillance. However, there remained a significant mean difference of 13.6ml between CT and 3D-US. Complete technical success of generating geometries for use in biomechanical analysis using 3D-US was only 5%. When the optimal results were used, a comparable CFD analysis under the conditions of steady, laminar and Newtonian flow was achieved. Using basic modelling assumptions in FEA, peak von Mises and principle wall stress was found to be at the same anatomical location on both the CT and 3D-US models but the 3D-US model overestimated the wall stress values by 41% and 51% respectively. Conclusions: 3D-US could be clinically implemented for intra-operative imaging and EVAR surveillance in specific cases. 3D-US volume measurement is feasible but future work should aim to improve accuracy and inter-observer reliability. Although the results of biomechanical analysis using the optimal results was encouraging and provided a proof-of-principal, there are a number of technical developments required to make this approach feasible in a larger number of patients.
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Hazard, Christopher R. "Real-time three-dimensional ultrasound imaging using synthetic aperture beamforming." The Ohio State University, 2001. http://rave.ohiolink.edu/etdc/view?acc_num=osu1486399160107451.
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Jayaram, Vijay. "The potential of three-dimensional ultrasound angiography in improving tumour diagnosis." Thesis, Imperial College London, 2002. http://hdl.handle.net/10044/1/8017.
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Luthy, Thierry. "Three-dimensional permeability measurements based on direct current and ultrasound monitoring techniques /." Zürich, 2003. http://e-collection.ethbib.ethz.ch/show?type=diss&nr=15050.
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Yeung, Tin-wai, and 楊天慧. "Use of three-dimensional ultrasound in the prediction of homozygous alpha0-thalassemia." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2008. http://hub.hku.hk/bib/B41290616.
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Cheong, Kah-bik, and 張嘉碧. "The use of volumetry by three-dimensional ultrasound in the first trimester." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2009. http://hub.hku.hk/bib/B43572339.
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Yeung, Tin-wai. "Use of three-dimensional ultrasound in the prediction of homozygous alpha0-thalassemia." Click to view the E-thesis via HKUTO, 2008. http://sunzi.lib.hku.hk/hkuto/record/B41290616.
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Cheong, Kah-bik. "The use of volumetry by three-dimensional ultrasound in the first trimester." Click to view the E-thesis via HKUTO, 2009. http://sunzi.lib.hku.hk/hkuto/record/B43572339.
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Fox, Timothy Stephen. "A three dimensional object rendering system." Virtual Press, 1991. http://liblink.bsu.edu/uhtbin/catkey/834152.
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This Creative Project has investigated current methods being used to produce computer animation. This investigation has resulted in the creation of a computer rendering program capable of generating animation. In order for the program to be able to execute though, a model of the object to be viewed must first be specified. This is done by assembling together a series of graphic primitives that when viewed collectively, form the desired model. Next, the rendering software is told where to point an imaginary camera in space. This camera is used to focus the image found in the viewfinder onto the computer monitor. Lastly, the imaginary camera is provided with a three dimensional path to follow as it tracks its way through space. By combining this data with the rendering software, a person viewing the resulting computer animation is able to interact with the computer model.Department of Computer Science
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Quartararo, John David. "Semi-automated segmentation of 3D medical ultrasound images." Worcester, Mass. : Worcester Polytechnic Institute, 2008. http://www.wpi.edu/Pubs/ETD/Available/etd-020509-161314/.
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Thesis (M.S.)--Worcester Polytechnic Institute.Keywords: 3d ultrasound; ultrasound; image processing; image segmentation; 3d image segmentation; medical imaging Includes bibliographical references (p.142-148).
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Dutton, Andrew William 1963. "A three-dimensional geometrical patient treatment planning program for scanned focussed ultrasound hyperthermia." Thesis, The University of Arizona, 1990. http://hdl.handle.net/10150/277295.
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A computer graphics workstation was developed to geometrically plan scanned focussed ultrasound hyperthermia treatments, and is currently in clinical use at the Arizona Health Sciences Center. The workstation allows the user to base the treatment plan on any set of hard copy images of the patient's treatment anatomy by using a frame grabber to import these images into the workstation. Anatomical structures are outlined by the user, and a three dimensional image is reconstructed using these outlines. A geometric outline of the ultrasound power deposition field is then inserted into the reconstructed patient anatomy, along with thermocouple junction locations. The use of a custom foam mold and fiducial marker system enables the location of the anatomical features to be determined in the treatment system's coordinates. A scan size and orientation that sufficiently sonicates the treatment volume can then be determined in an interactive three dimensional environment.
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Tung, D.-K. "A knowledge-based three-dimensional modelling system." Thesis, Swansea University, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.639269.
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As manufacturers strive towards high-quality production, automated industrial inspection is a potent resource in the design of cost-effective systems which can ensure that products meet all their design specifications. However, in reality, only in well-controlled applications are economically usable systems being taken into daily use. Where such systems are being used, they are seen to be primarily addressing 2-dimensional inspection problems. This is not surprising, given the highly complex problems which must be dealt with in practical, real-world environments. However, there is an urgent need to move towards acceptable machine-vision systems which not only can operate in industrial environments, but also offer the benefits of 3-dimensional visual representation - so vital in any real inspection situation. A fundamental aspect of any inspection system is the development of inspection models - to be used in subsequent inspection procedures. The generation of these models is a non-trivial task, and one which is increasingly being seen to be best done using operator assistance - as shown, for example, in the work of Chen [34]. However, most current work in such model generation has been tackled in the 2-D arena. This thesis addresses the problem of providing high-quality, visually meaningful, representations of 3-dimensional bodies, drawing information from 2 simple, but industrially-rugged, 2-dimensional images, and using operator assistance to determine the final models. When combined, the resulting 3-dimensional representation provides a valuable reference to an object's total physical structure. The models themselves allow for accurate inspection of the objects' physical parameters.
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Seely, Richard D. "On a three-dimensional gait recognition system." Thesis, University of Southampton, 2010. https://eprints.soton.ac.uk/159881/.
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The University of Southampton Multi-Biometric Tunnel is a high performance data-capture and recognition system; designed with airports and other busy public areas in mind. It is able to acquire a variety of non-contact biometrics in a non-intrusive manner, requiring minimal subject cooperation. The system uses twelve cameras to record gait and perform three-dimensional reconstruction; the use of volumetric data avoids the problems caused by viewpoint dependence - a serious problem for many gait analysis approaches. The early prototype by Middleton et al. was used as the basis for creating a new and improved system, designed for the collection of a new large dataset, containing gait, face and ear. Extensive modifications were made, including new software for managing the data collection experiment and processing the dataset. Rigorous procedures were implemented to protect the privacy of participants and ensure consistency between capture sessions. Collection of the new multi-biometric dataset spanned almost one year; resulting in over 200 subjects and 2000 samples. Experiments performed on the newly collected dataset resulted in excellent recognition performance, with all samples correctly classified and a 1.58% equal error rate; the matching of subjects against previous samples was also found to be reasonably accurate. The fusion of gait with a simple facial analysis technique found the addition of gait to be beneficial -- especially at a distance. Further experiments investigated the effect of static and dynamic features, camera misalignment, average silhouette resolution, camera layout, and the matching of outdoor video footage against data from the Biometric Tunnel. The results in this thesis prove significant due to the unprecedented size of the new dataset and the excellent recognition performance achieved; providing a significant body of evidence to support the argument that an individual's gait is unique. L. Middleton, D. K. Wagg, A. I. Bazin, J. N. Carter and M. S. Nixon. A smart environment for biometric capture. Automation Science and Engineering, Proceedings of IEEE International Conference on, 57-62, 2006.
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Barreto, Rosilma Gorete Lima. "Dynamic two-dimensional anorretal ultrasound in the diagnosis of Anismus in adult women - comparative study to the anal manometria and dynamic three-dimensional anorretal ultrasound." Universidade Federal do CearÃ, 2007. http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=1171.
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CoordenaÃÃo de AperfeiÃoamento de Pessoal de NÃvel SuperiorAnismus is one of the most frequent disease in carrying patients of obstructed defecation and it is being present in about 50.0% of the constipated patients. The aim of this study is to demonstrate the use of the bi-dimensional anorectal ultrasound (2-D USD) for the diagnosis of anismus and comparing the results with the anus manometry and the three-dimensional anorectal ultrasound (3-D USD). Sixty adult women with obstructed defecation symptoms were evaluated in this prospective and comparative study, coming from Colorectal Unit of the Hospital UniversitÃrio Walter CantÃdio of the Universidade Federal do CearÃ, between September 2006 to March 2007. All the patients were initially submitted to anus manometry (BAD) and then divided in two groups with 30 patients each. Group I was formed by patients without anismus at the mean age of 48,63 (24 the 69) years, while group II with carrying patients with anismus at the mean age of 51,20 (27 the 78) years. After that, patients of both groups were submitted to the 3-D and 2-D USD by an examiner who was unaware of the results of the manometries. The average size of the gotten angle with the 3-D USD at rest position of group I was 87.28Â Â 0.80Â (76,5Â-96,2Â) and of 87.87Â Â 0.99Â (78,5Â-109,4Â) in group II. (p=0,3220). The average size of the angle during the evacuatory effort of group I was of 93.25Â Â 1.49Â (74,9Â-106,9Â) and of 85.27Â Â 1.35Â (72,0Â- 101,8Â) in group II, (p=0.007). The average size of the gotten angle with the USD 2-D at rest positions of group I was 62.61Â Â 1.15Â (50,9Â-75,0Â) and of 65.51Â Â 0.89Â (50,8Â-73,0Â) in group II (p=0,0257). The average size of the angle during the evacuating effort of group I was of 59.75Â Â 1.42Â (44,0Â-73,0Â) and of 69.40Â Â 1.06Â (52,6Â-79,5Â) in group II, (p< 0,001). Comparing the differences of the angles size at rest position and during evacuatory effort of the patients of group I with group II, using 2-D and 3-D USD, there was statistically significant difference (p< 0,0001). Comparing the results between the 2-D USD with the manometry, there was agreement in 86,67% and 83,33% of the patients of group I and group II respectivelly. Comparing the results between the 2-D and 3-D USD, there was agreement of 93,33% in the evaluation of the patients of group I and of 90,0% of the patients of group II. The agreement among the three methods was 86,67% as positive predictive value and 83.33% as negative predictive value. It is concluded that the use the 2-D USD was considered efficient in the diagnosis of anismus by the high indication of agreement among the three used methods
Anismus à uma das afecÃÃes mais freqÃentes em pacientes portadores de evacuaÃÃo obstruÃda, estando presente em cerca de 50.0% dos pacientes constipados. O objetivo deste trabalho à avaliar se o USD 2-D faz o diagnÃstico de anismus, quando comparado a manometria anal e ao USD 3-D. Foram avaliadas neste estudo prospectivo e comparativo 60 mulheres adultas com sintomas de evacuaÃÃo obstruÃda, provenientes do ServiÃo de Coloproctologia do Hospital UniversitÃrio Walter CantÃdio da Universidade Federal do CearÃ, no perÃodo entre setembro de 2006 a marÃo de 2007. Todas as pacientes foram inicialmente submetidas à manometria anal (MA) e, distribuidas em dois grupos com 30 pacientes cada. O grupo I foi constituÃdo por pacientes sem anismus e com mÃdia de idade 48,63 (24 a 69) anos, enquanto o grupo II com pacientes portadoras de anismus e com mÃdia de idade 51,20 (27 a 78) anos. Em seguida, as pacientes de ambos os grupos foram submetidas à USD 3-D E 2-D por um examinador que desconhecia o resultado da manometria. O tamanho mÃdio do Ãngulo obtido com o USD 3-D no repouso do grupo I foi 87.28  0.80 (76,5Â-96,2Â) e de 87.87  0.99 (78,5Â-109,4Â) no grupo II. (p=0,3220). O tamanho mÃdio do Ãngulo no esforÃo evacuatÃrio do grupo I foi de 93.25  1.49Â(74,9Â-106,9Â) e de 85.27  1.35Â(72,0Â-101,8Â) no grupo II, (p=0.007). O tamanho mÃdio do Ãngulo obtido com a USD 2-D no repouso do grupo I foi 62.61  1.15Â(50,9Â-75,0Â) e de 65.51  0.89Â(50,8Â-73,0Â) no grupo II (p=0,0257). O tamanho mÃdio do Ãngulo no esforÃo evacuatÃrio do grupo I foi de 59.75  1.42Â(44,0Â-73,0Â) e de 69.40  1.06Â(52,6Â-79,5Â) no grupo II, (p<0.001). Comparando a diferenÃa do tamanho dos Ãngulos no repouso e no esforÃo evacuatÃrio dos pacientes do grupo I com o grupo II, ao USD 2-D e 3-D, foi observado diferenÃa estatisticamente significante (p< 0,0001). Comparando os resultados obtidos ao USD 2-D com a manometria, houve concordÃncia em 86,67% das pacientes de ambos os grupos. Comparando os resultados obtidos entre o USD 2-D com o 3-D, houve concordÃncia de 93,33% na avaliaÃÃo das pacientes do grupo I e de 90,0% das pacientes do grupo II.A concordÃncia entre os trÃs mÃtodos foi de 86,67% como valor preditivo positivo e 83,33% como valor preditivo negativo. Conclui-se que a o USD 2-D foi eficaz em averiguar o diagnÃstico do anismus pelo elevado Ãndice de concordÃncia entre os trÃs mÃtodos utilizados
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Chen, Yong. "Daily three-dimensional ultrasound imaging for Monte Carlo based adaptive radiotherapy of prostate cancer." Thesis, McGill University, 2009. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=66928.
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This thesis retrospectively analyzes prostate's daily motion provided by three-dimensional US localization and investigates its dosimetric impacts based on XVMC calculation which takes into account patient geometry, heterogeneity and prostate motion correction. The retrospective analysis on 32 prostate patients shows that the mean SD displacements of prostate in the AP, SI, and RL directions are -3.3 7.9 mm, -1.1 6.4 mm, -0.2 5.6 mm, respectively. The largest rotation occurs about lateral axis with mean SD of -0.9 4.6, ranging between -6.7 and 8.0 from a preliminary study including three patients. To assess the dosimetric impacts of prostate motion, five motion scenarios including with and without prostate translation and correction, with translation and rotation but no correction or only having translation correction are simulated. Analysis based on dose-volume histograms and isodose curves shows that prostate motion (translation and rotation) will deteriorate the dose delivered to patient target and OARs. With translation correction method, the degraded patient dose could be recovered nearly completely. For the scenarios with both translation and rotation, translation correction method could dramatically improve the degraded patient dose, but could not completely eliminate the dosimetric impact of prostate motion. Besides, the dosimetric impact of metal prosthesis in three patients has been analysed as well. Up to 5% discrepancies in their D90%, D95%, V90%, and D95% for PTV have been observed.Le mouvement de la prostate est un problème critique dans le traitement conforme du cancer de la prostate, le plus commun cancer parmi les hommes au Canada. La radiothérapie guidée par l'image (IGRT) utilisant les images ultrasons (US) quotidiennes est une technique largement utilisée pour régler ce problème. Une nouvelle technique de localisation ultrasons en trois dimensions, basée sur une méthode de vérification intra modalités, a été testée à l'Hôpital General de Montreal en 2005. L'objectif principal de cette thèse a été de mieux quantifier l'amplitude du mouvement de la prostate à travers une analyse rétrospective de 32 patients et d'évaluer son impacte dans la dosimétrie des traitements de la prostate avec et sans localisation US. L'analyse rétrospective a montré que la moyenne écart-type des mouvements de la prostate dans les directions AP, SI et DG est de -3.3 7.9 mm, -1.1 6.4 mm et -0.2 5.6 mm, respectivement. La plus grande rotation survient autour de l'axe latérale, avec une moyenne écart-type de -0.9 4.6, s'échelonnant entre -6.7 et 8.0. Pour estimer l'impacte dosimétrique du mouvement rigide de la prostate, la dose a été calculée en utilisant la méthode XVMC, qui prend en considération la géométrie du patient, les hétérogénéités et les corrections pour le mouvement. Une déviation moyenne de la D95% de jusqu'à -11.9% a été observe pour le PTV, -5.1% pour le CTV et -4.2% pour le GTV. Le V95% du PTV a été réduit par un facteur de -22.2% lorsque la translation quotidienne de la prostate était présente mais aucune correction n'a été appliquée. La dégradation de la dose à la cible a pu être corrige presque complètement en appliquant une correction du mouvement de translation, cependant lorsque la rotation a été prise en compte, le recouvrement de la dose a été moins adéquat. L'effet des prothèses m
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Apostolopoulos, Vasileios. "Real time intraoperative three dimensional ultrasound in biopsy and resection of intrinsic brain tumours." Thesis, Imperial College London, 2013. http://hdl.handle.net/10044/1/24922.
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There is growing evidence that maximal surgical resection of malignant gliomas is beneficial, both by increasing the progression free survival (Stummer, Pichlmeier et al. 2006) and also by facilitating postoperative chemotherapy and radiotherapy (Stupp, Mason et al. 2005). In this context there has been an increased need for real time intraoperative imaging in brain tumour surgery. The complex theatre arrangements, prohibitive cost and prolonged theatre time has restricted the wide application of intraoperative MRI (iMRI). Modern intraoperative ultrasound, which in the past has been relatively underused in oncological neurosurgery, is affordable, and easy to use (Unsgaard, Ommedal et al. 2002), but has not been robustly validated. This study attempts to histologically validate the accuracy of the intraoperative US and to explore its potential as an intraoperative navigation tool, which can accurately guide biopsies and resections of intrinsic brain tumours. The digital data extracted from US images obtained during ultrasound guided biopsies was correlated with the histology of the relevant specimens. Image analysis of selected regions of interest (ROI) was employed to extract quantitative parameters from the digital ultrasound images. The mean pixel brightness (MPB) and the standard deviation (SD) were correlated with histological parameters. The pattern of histograms from the selected ROIs was observed and correlated with the histological findings. A close correlation was observed between mean pixel brightness (MPB), an objective measure of echogenicity, and cellularity and an equally close correlation between the standard deviation (SD) and the intrinsic cellular diversity of the analysed areas. These two together, despite not being specific, can indirectly suggest the nature of the tumour and also reflect the sensitivity of intraoperative US to detect the presence and the extent of intrinsic brain tumours. Our findings could have translational potential as an intraoperative guidance tool.
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Mavrelos, Dimitrios. "The role of three-dimensional ultrasound in the diagnosis and treatment of uterine pathology." Thesis, King's College London (University of London), 2012. https://kclpure.kcl.ac.uk/portal/en/theses/the-role-of-threedimensional-ultrasound-in-the-diagnosis-and-treatment-of-uterine-pathology(36cb7b0f-9020-44de-b8e9-f5d93904e3b4).html.
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This thesis investigated the role of three – dimensional transvaginal ultrasound in the identification, classification and management of uterine pathology. We performed serial measurements of fibroids over a period of time to examine their natural history. We found that fibroids tend to grow at a relatively fast average rate in pre-menopausal women, which is influenced by the initial fibroid volume and patients’ demographic characteristics. Our findings could help to rationalise the follow up and plan better the treatment of women with fibroids. Our results also provided novel insights into the possible pathogenesis of fibroids. 3D – SIS has been previously demonstrated to be equivalent to hysteroscopy to measure the degree of submucous fibroids protrusion into the endometrial cavity. However compared to hysteroscopy, 3D – SIS provides additional information including objective measurement of fibroid size and position. We evaluated these additional ultrasonic variables and identified diameter and size of the intramural portion as predictive of complete resection at a single TCRF. GnRH analogues have been given to women with submucous fibroids before transcervical resection to improve the chance of complete resection. However evidence for this practice is limited and the treatment is associated with significant side effects. We carried out a double - blind , placebo – controlled, randomized trial which did not demonstrate a benefit in the preoperative administration of GnRH analogues in women scheduled for TCRF. This thesis also investigated the role of 3D ultrasound in the diagnosis and treatment of endometrial cancer. Currently women with postmenopausal bleeding are investigated by transvaginal ultrasound to measure endometrial thickness. This results in a substantial 22 number of women needing endometrial biopsy to confirm benignity. We evaluated the ability of three 3D - PDA with objective quantification of vascularity indices to differentiate between benign and malignant lesions in women at high risk of endometrial cancer. We found that this shows promise but does not eliminate the need for biopsy. Currently women diagnosed with cancer undergo surgical staging that increases surgical morbidity. We investigated the usefulness of endometrial volume measurement in such patients to predict cancer stage which may be used in preoperative planning.
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Wygant, Ira Oaktree. "Three-dimensional ultrasound imaging using custom integrated electronics combined with capacitive micromachined ultrasonic transducers /." May be available electronically:, 2008. http://proquest.umi.com/login?COPT=REJTPTU1MTUmSU5UPTAmVkVSPTI=&clientId=12498.
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Gunter, Derrick. "Objectif, a three-dimensional graphics system in motif." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp04/mq23803.pdf.
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Liu, Mengfei, and 刘梦菲. "Epithelial morphogenesis in three-dimensional cell culture system." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2014. http://hdl.handle.net/10722/208611.
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In human body, the most common structures formed by epithelial cells are hollow cysts or tubules. The key feature of the cysts and tubules is the central lumen, which is lined by epithelial cell sheets. The central lumen allows material exchange, thus it is indispensable for the proper function of the epithelial tissue.
In order to understand the way that the epithelial cells form highly specialized structure, an in vitro three-dimensional (3D) culture system was established. The Caco-2 cells were embedded in reconstituted basement membrane termed matrigel, whose biochemical constitution and physical properties were similar with the in vivo environment. The Caco-2 cells in matrigel spontaneously formed spherical multi-cell cysts, which could continuously expand. The confocal imaging and reconstruction technique helped understand the cyst structure and its formation process. The cysts developed central lumen surrounded by a layer of polarized cells. The apical domain of the cells faced the lumen, while the basal domain attached to the extracellular matrix.
In the mature cysts, fluid was secreted by the cells around the lumen at the apical domain, and accumulated in the central lumen. The laser burning experiment showed that the intraluminal pressure was higher than the outer environment. The intact cell sheet was required to keep the engorged morphology of the cysts. The tension of the cell layer balanced with the intraluminal pressure.
To investigate the effect of pressure on cyst development, the cysts were treated with cholera toxin, which could increase intraluminal pressure through promoting apical secretion. The time-lapse images showed that under cholera toxin treatment, the expansion of the cysts was accelerated. The high intraluminal pressure led to shape change of thecells, followed by increase in cell proliferation rate. Cholera toxin itself could not promote cell growth. In the3D cultured cysts, it was the increased intraluminal pressure that directly induced the acceleration of cell proliferation. It indicated that not only biochemical signals, but also mechanical force, contributed to epithelial morphogenesis.
The mechanical stimulation could be converted into biochemical signals, further affect cell behavior. In response to mechanical stimulation, the focal adhesion kinase was activated in the cells around the cyst lumen. Furthermore, the microarray analysis suggested that multiple signaling pathways were altered under intraluminal pressure stimulation, including the pathways related to cytoskeleton organization, cell cycle and cell adhesion.
Taken together, comparing with the conventional two-dimensional cell culture on rigid surface, the three-dimensional culture system provided the cells a more physiological environment. The 3D culture system allows the epithelial cells to form well-organized hollow structure. It is a convenient model for investigating the process and mechanism of epithelial morphogenesis.published_or_final_version
Biochemistry
Doctoral
Doctor of Philosophy
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Bero, Mamdouh A. "Development of a three-dimensional radiation dosimetry system." Thesis, University of Surrey, 2001. http://epubs.surrey.ac.uk/719/.
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Rowe, Robert Kjell. "A system for three-dimensional SPECT without motion." Diss., The University of Arizona, 1991. http://hdl.handle.net/10150/185409.
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This dissertation presents the results of an investigation into the performance characteristics of a unique hemispherical SPECT (single-photon emission computed tomography) imaging system capable of producing three-dimensional (3D) tomographic images of the human brain. The system is completely stationary and collects all necessary views of the patient simultaneously, with no system motion. The imager consists of twenty small (10cm x 10cm crystal area), digital gamma cameras arranged in a hemispherical pattern around the patient's head and a hemispherical lead aperture. The hemispherical aperture is positioned between the cameras and the head and contains a large number of pinholes; in this way each camera sees a number of overlapping pinhole projections of the radioactive distribution within the patient's brain. The initial investigation of the performance characteristics of a 3D SPECT system of this design were carried out using a computer simulation in which effects due to radiometry, finite pinhole size, finite detector resolution, photon noise, and object attenuation were included. We used a digital 3D brain phantom as the test object and an iterative search algorithm to perform the reconstructions. The simulations were used to compare the performance of a variety of system configurations. Based upon the results of the simulation study, we constructed a laboratory prototype of the 3D SPECT system, which we used to further characterize the expected performance of a clinical imaging system of the same design. Prior to collecting SPECT data we calibrated the imaging system, which required that we efficiently measure and store the spatially variant system response function. These calibration data were then included in the reconstructions of the SPECT phantoms that we imaged. A number of different SPECT phantoms were imaged to demonstrate the system performance. We measured a reconstructed spatial resolution of 4.8mm full-width at half-maximum and a full-system sensitivity of 36cps/μCi, where both values were measured for a point source in air located at the center of the field of view. We also describe an analysis that we performed to determine the equivalent, non-multiplexed system sensitivity; using this method, we found that the equivalent sensitivity was 79% of the measured value for the system configuration and the particular task that we investigated.
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Alharbi, A. A. H. "Utilising a three-dimensional system to understand nephrogenesis." Thesis, University College London (University of London), 2018. http://discovery.ucl.ac.uk/10050316/.
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Monolayer culture of kidney cells and ex vivo and in vitro experiments using model organisms are commonly used in studies of renal development, yet it is unclear how these correlate with human kidney development in vivo. Recent research aimed at engineering new kidneys from dissociated renal cells demonstrates that it is feasible to generate multiple nephron segments, resulting in a three-dimensional, miniature kidney like structure, albeit with poor overall structural organisation than a normal kidney. This has been done predominantly using cells obtained directly from mouse embryos within the first two days of kidney formation, and it is not thought to be possible to use older murine organs. In theory, it should also be possible to generate neo-kidneys using human renal progenitor cells from fetal kidneys; however, these can never be obtained early enough to correspond to the mouse stages that are normally used. Here, I not only show that dissociated renal cells from older embryonic mice are able to generate multiple nephron segments, but also that human fetal kidney cells are able to produce typical nephron elements. Dissociated renal cells from older embryonic mice not only generate structural elements resembling normal kidney tubules and glomeruli but they also have anion uptake capacity as might be seen in vivo, illustrating functional capacity. Human fetal kidney cells generated from gestational ages between 10 and 16 weeks were additionally able to produce apparently typical nephron elements. Some inter-species differences were observed in the morphology of the ureteric buds, with fewer branches found in the human compared to the mouse, along with an obvious difference in the expression pattern of CALB1+ cells. However, the human cell-derived neo-kidneys expressed functional anion and cation transporters. This thesis demonstrates that organotypic renal structures with functional ion transporters can be generated from human fetal kidney cells. This provides us with a novel approach to understand and examine nephrogenesis and, essentially, to model kidney disease from a human perspective.
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Sidney, Daniel Alan 1966. "Three-dimensional ultrasound power deposition modeling, thermal field visualzation, and clinical integration for hyperthermia therapy." Thesis, Massachusetts Institute of Technology, 1997. http://hdl.handle.net/1721.1/43464.
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Thesis (Ph. D.)--Massachusetts Institute of Technology, Whitaker College of Health Sciences and Technology, 1997.Vita.
Includes bibliographical references (p. 257-264).
by Daniel Alan Sidney.
Ph.D.
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Shekhar, Raj. "Fusion of intravascular ultrasound and biplane angiography for accurate three-dimensional reconstruction of coronary arteries /." The Ohio State University, 1997. http://rave.ohiolink.edu/etdc/view?acc_num=osu148794532075916.
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Liu, Hang. "Studies of the Nuclear Three-Body System with Three Dimensional Faddeev Calculations." Ohio University / OhioLINK, 2005. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1127332785.
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Zhang, Jinlei. "Camera calibration for a three-dimensional range finding system." Virtual Press, 1995. http://liblink.bsu.edu/uhtbin/catkey/958780.
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The purpose of this project is to develop the procedures to perform the camera calibration in a three dimension range finding system. The goal is to have a system that will provide reasonably accurate range data which can be used in further three-dimensional computer vision research such as edge detection, surface recovery and object recognition. In this project, an active lighting, optical, triangulation based range finding system has been developed. The software system is designed in object oriented technology and implemented using the C++ programming language. The overall performance of the system is investigated and the system has achieved 0.5 mm (or 4%) accuracy. A review of three range data acquisition techniques is given. Based on the analysis to the current system, suggestions to future improvement are also provided.Department of Physics and Astronomy