Articles de revues : « Arm scanner »

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Rossi, Cesare, et Sergio Savino. « A Robotic System to Scan and Reproduce Object ». Journal of Robotics 2011 (2011) : 1–11. http://dx.doi.org/10.1155/2011/168481.

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An application of a robotic system integrated with a vision system is presented. The robot is a 3-axis revolute prototype, while the vision system essentially consists in a laser scanner made up of a camera and a linear laser projector. Both the robotic and the video system were designed and built at DIME (Department of Mechanical Engineering for Energetics), University of Naples Federico II. The presented application essentially consists of a laser scanner that is installed on the robot arm; the scanner scans a 3D surface, and the data are converted in a cloud of points in the robot’s workspace. Then, starting from those points, the end-effector trajectories adopted to replicate the scanned surface are calculated; so, the same robot, by using a tool, can reproduce the scanned object. The software was developed also at the DIME. The adopted tool was a high-speed drill, installed on the last link of the robot arm, with a spherical milling cutter in order to obtain enough accurate surfaces by the data represented by the cloud of points. An algorithm to interpolate the paths and to plan the trajectories was also developed and successfully tested.

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Rehany, N., A. Barsi et T. Lovas. « CAPTURING FINE DETAILS INVOLVING LOW-COST SENSORS –A COMPARATIVE STUDY ». ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences XLII-2/W8 (14 novembre 2017) : 213–20. http://dx.doi.org/10.5194/isprs-archives-xlii-2-w8-213-2017.

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Capturing the fine details on the surface of small objects is a real challenge to many conventional surveying methods. Our paper discusses the investigation of several data acquisition technologies, such as arm scanner, structured light scanner, terrestrial laser scanner, object line-scanner, DSLR camera, and mobile phone camera. A palm-sized embossed sculpture reproduction was used as a test object; it has been surveyed by all the instruments. The result point clouds and meshes were then analyzed, using the arm scanner’s dataset as reference. In addition to general statistics, the results have been evaluated based both on 3D deviation maps and 2D deviation graphs; the latter allows even more accurate analysis of the characteristics of the different data acquisition approaches. Additionally, own-developed local minimum maps were created that nicely visualize the potential level of detail provided by the applied technologies. Besides the usual geometric assessment, the paper discusses the different resource needs (cost, time, expertise) of the discussed techniques. Our results proved that even amateur sensors operated by amateur users can provide high quality datasets that enable engineering analysis. Based on the results, the paper contains an outlook to potential future investigations in this field.

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Svahn, Tony M., Lovre Peric et Jennifer C. Ast. « Influence of Different Arm Positions in the Localizer Radiograph(s) on Patient Dose during Exposure-Controlled CT Examinations of the Neck to Pelvis ». Tomography 7, n^o 3 (29 juillet 2021) : 313–22. http://dx.doi.org/10.3390/tomography7030028.

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Our aim was to examine the impact of different arm positions during imaging of the localizer radiograph(s) on effective dose for exposure-controlled computed tomography (CT) (Siemens/Canon) scans of the neck to pelvis. An anthropomorphic whole-body phantom was scanned from the neck to pelvis with the arms positioned in three different ways during the acquisition of the localizer radiograph: (i) above the head, (ii) alongside the trunk, and (iii) along the trunk with the hands placed on the abdomen. In accordance with clinical routines, the arms were not included in the subsequent helical scans. Effective doses were computed to a standard-sized patient (male/female) using a dedicated system-specific Monte Carlo-based software. Effective doses for the Canon CT scanner for the different alternatives (male/female) were (a) 5.3/6.62 mSv, (b) 5.62/7.15 mSv and (c) 5.92/7.44 mSv. For the Siemens CT scanner, effective doses were (a) 4.47/5.59 mSv, (b) 5.4/6.69 mSv and (c) 5.7/6.99 mSv. Arms placed above the head during localizer radiograph imaging in the current CT procedures substantially reduced the total effective dose to the patient.

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Aodai, Toshiyuki, et Shigeki Toyama. « Development of MRI Compatible Manipulandum for Hand and Arm Movement ». Journal of Robotics and Mechatronics 21, n^o 1 (20 février 2009) : 20–27. http://dx.doi.org/10.20965/jrm.2009.p0020.

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The paper subscribes development of Magnetic Resonance Imaging (MRI) compatible using an ultrasonic motor, to work within the limits of MRI scanner workspace and environment, dimensions involving upper-limbs biomechanics. The manipulandum consists of hand mechanism and an arm-reaching mechanism having a two-degree-freedom (2DOF) haptic interface enabling human subject to conduct reaching movement comfortably within MRI workspace. The kinematics structure of the manipulandum is optimized for MRI space and movement. We have confirmed the manipulandum's MRI compatibility in experiments.

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Messer, Dolores, Michelle S. Svendsen, Anders Galatius, Morten T. Olsen, Vedrana A. Dahl, Knut Conradsen et Anders B. Dahl. « Measurement error using a SeeMaLab structured light 3D scanner against a Microscribe 3D digitizer ». PeerJ 9 (20 août 2021) : e11804. http://dx.doi.org/10.7717/peerj.11804.

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Background Geometric morphometrics is a powerful approach to capture and quantify morphological shape variation. Both 3D digitizer arms and structured light surface scanners are portable, easy to use, and relatively cheap, which makes these two capturing devices obvious choices for geometric morphometrics. While digitizer arms have been the “gold standard”, benefits of having full 3D models are manifold. We assessed the measurement error and investigate bias associated with the use of an open-source, high-resolution structured light scanner called SeeMaLab against the popular Microscribe 3D digitizer arm. Methodology The analyses were based on 22 grey seal (Halichoerus grypus) skulls. 31 fixed anatomical landmarks were annotated both directly using a Microscribe 3D digitizer and on reconstructed 3D digital models created from structured light surface scans. Each skull was scanned twice. Two operators annotated the landmarks, each twice on all the skulls and 3D models, allowing for the investigation of multiple sources of measurement error. We performed multiple Procrustes ANOVAs to compare the two devices in terms of within- and between-operator error, to quantify the measurement error induced by device, to compare between-device error with other sources of variation, and to assess the level of scanning-related error. We investigated the presence of general shape bias due to device and operator. Results Similar precision was obtained with both devices. If landmarks that were identified as less clearly defined and thus harder to place were omitted, the scanner pipeline would achieve higher precision than the digitizer. Between-operator error was biased and seemed to be smaller when using the scanner pipeline. There were systematic differences between devices, which was mainly driven by landmarks less clearly defined. The factors device, operator and landmark replica were all statistically significant and of similar size, but were minor sources of total shape variation, compared to the biological variation among grey seal skulls. The scanning-related error was small compared to all other error sources. Conclusions As the scanner showed precision similar to the digitizer, a scanner should be used if the advantages of obtaining detailed 3D models of a specimen are desired. To obtain high precision, a pre-study should be conducted to identify difficult landmarks. Due to the observed bias, data from different devices and/or operators should not be combined when the expected biological variation is small, without testing the landmarks for repeatability across platforms and operators. For any study necessitating the combination of landmark measurements from different operators, the scanner pipeline will be better suited. The small scanning-related error indicates that by following the same scanning protocol, different operators can be involved in the scanning process without introducing significant error.

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Nonent, M. « Comparaison ed-scanner-ARM pour l’evaluation des stenoses de l’artere carotide (etude carmedas) ». Journal de Radiologie 86, n^o 10 (octobre 2005) : 1311. http://dx.doi.org/10.1016/s0221-0363(05)75396-8.

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Koch, B., R. Leblebici, A. Martell, S. Jörissen, K. Schilling et A. Nüchter. « EVALUATING CONTINUOUS-TIME SLAM USING A PREDEFINED TRAJECTORY PROVIDED BY A ROBOTIC ARM ». ISPRS Annals of Photogrammetry, Remote Sensing and Spatial Information Sciences IV-2/W4 (13 septembre 2017) : 91–98. http://dx.doi.org/10.5194/isprs-annals-iv-2-w4-91-2017.

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Recently published approaches to SLAM algorithms process laser sensor measurements and output a map as a point cloud of the environment. Often the actual precision of the map remains unclear, since SLAMalgorithms apply local improvements to the resulting map. Unfortunately, it is not trivial to compare the performance of SLAMalgorithms objectively, especially without an accurate ground truth. This paper presents a novel benchmarking technique that allows to compare a precise map generated with an accurate ground truth trajectory to a map with a manipulated trajectory which was distorted by different forms of noise. The accurate ground truth is acquired by mounting a laser scanner on an industrial robotic arm. The robotic arm is moved on a predefined path while the position and orientation of the end-effector tool are monitored. During this process the 2D profile measurements of the laser scanner are recorded in six degrees of freedom and afterwards used to generate a precise point cloud of the test environment. For benchmarking, an offline continuous-time SLAM algorithm is subsequently applied to remove the inserted distortions. Finally, it is shown that the manipulated point cloud is reversible to its previous state and is slightly improved compared to the original version, since small errors that came into account by imprecise assumptions, sensor noise and calibration errors are removed as well.

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Cuesta, E., B. J. Alvarez, S. Martinez-Pellitero, J. Barreiro et H. Patiño. « Metrological evaluation of laser scanner integrated with measuring arm using optical feature-based gauge ». Optics and Lasers in Engineering 121 (octobre 2019) : 120–32. http://dx.doi.org/10.1016/j.optlaseng.2019.04.007.

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Rotar, Raul Nicolae, Anca Jivanescu, Codruta Ille, Angela Codruta Podariu, Daniela Elisabeta Jumanca, Ana-Maria Matichescu, Octavia Balean et Laura Cristina Rusu. « Trueness and Precision of Two Intraoral Scanners : A Comparative In Vitro Study ». Scanning 2019 (21 octobre 2019) : 1–6. http://dx.doi.org/10.1155/2019/1289570.

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The aim of this study was to evaluate the accuracy of two intraoral scanners used in the dental office. A molar fixed in a typodont was prepared for a ceramic onlay. The preparation was scanned using a high-resolution scanner (reference scanner) and saved as stereolithography (STL) format. The prepared resin molar was scanned again using the intraoral scanners, and all the scans were saved as well in STL format. All STL files were compared using metrology software (Geomagic Control X). Overlapping the meshes allowed the assessment of the scans in terms of trueness and precision. Based on the results of this study, the differences of trueness and precision between the intraoral scanners were minimal.

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Zhou, Song, Wen Yang, Yimin Wang, Zhong Chen et Tianran Yuan. « Handheld optical coherence tomography scanner using a common-path probing arm with long working distance ». Optics Communications 499 (novembre 2021) : 127254. http://dx.doi.org/10.1016/j.optcom.2021.127254.

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Zhang, Zhaohua, Jun Ni et Ying Zhou. « The Effect of Arm Postures and Garment Style on Local Mobility and Thermal Insulation ». AATCC Journal of Research 9, n^o 1 (janvier 2022) : 12–22. http://dx.doi.org/10.1177/23305517211060813.

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Heat transfer in clothing can be influenced by posture change of the human body and garment pattern design. In this study, the volume of the air gaps and the contact area were investigated for different arm postures of a thermal manikin using a three-dimensional body scanner, and the effect of garment pattern design was analyzed. Furthermore, the local thermal insulation of different body parts of the thermal manikin was tested for six kinds of arm postures when the manikin was dressed in various experimental garments. Both arm postures and garment styles had a strong effect on the local air gap distributions. The air gap volume decreased, and the contact area increased with the growth of protraction angles of arms. The human tests also indicated that the range of arm motion was improved, and better flexibility was perceived compared with the original style. A significant positive correlation between thermal insulation and air gap volume ( r = 0.753, p < 0.001) was found.

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Burde, Alexandru Victor, Marius Manole, Radu-Septimiu Campian, Cosmin Sinescu et Sorana Baciu. « In vitro Comparison of Accuracy of Two Scanners Used in Dental Medicine ». Revista de Chimie 70, n^o 7 (15 août 2019) : 2344–46. http://dx.doi.org/10.37358/rc.19.7.7336.

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This experimental study aims to highlight and compare the resolution and accuracy (trueness and fidelity) of an intraoral scanner and a laboratory scanner. In order to achieve the aim of this study, an experimental model consisting of a die with a standard preparation for a porcelain-fused to metal crown was manufactured from a physiognomic polymethylmethacrylate resin. The experimental model was scanned with an industrial CT to obtain the virtual reference model. Then, the die was scanned 15 times with each scanner. In order to asses trueness, comparisons were made with the virtual reference model, and for fidelity, the first scan in the series was compared with the following scans. In regards to the trueness of the scanners, the average deviation for the laboratory scanner is 4.31 and 17.34 mm for the intraoral scanner. When comparing the serial scannings� of the same die, the lowest recorded deviation is 6.4 mm for the laboratory scanner and 21.57mm for the intraoral scanner. For both fidelity and trueness, the F test demonstrates that there is a statistically significant difference between the scanners and the applied T-tests confirm the lower degree of error-rate generation by the laboratory scanner. The dimensional limitations imposed for the intraoral scanners have a direct consequence on their trueness and fidelity when compared to their laboratory counterparts.

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Bilinauskaite, Milda, Vishveshwar R. Mantha, Abel I. Rouboa, Pranas Ziliukas et António J. Silva. « A Computational Fluid Dynamics Study of Propulsion Due to the Orientation Effects of Swimmer’s Hand ». Journal of Applied Biomechanics 29, n^o 6 (décembre 2013) : 817–23. http://dx.doi.org/10.1123/jab.29.6.817.

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The aim of the article is to determine the hydrodynamic characteristics of a swimmer’s scanned hand model for various possible combinations of both the angle of attack and the sweepback angle, simulating separate underwater arm stroke phases of front crawl swimming. An actual swimmer’s hand with thumb adducted was scanned using an Artec L 3D scanner. ANSYS Fluent code was applied for carrying out steady-state computational fluid dynamics (CFD) analysis. The hand model was positioned in nine different positions corresponding to the swimmer’s hand orientations (angle of attack and sweepback angle) and velocities observed during the underwater hand stroke of front crawl. Hydrodynamic forces and coefficients were calculated. Results showed significantly higher drag coefficient values in the pull phase, when compared with previous studies under a steady-state flow condition. The mean value of the ratio of drag and lift coefficients was 2.67 ± 2.3 in underwater phases. The mean value of the ratio of drag and lift forces was 2.73 ± 2.4 in underwater phases. Moreover, hydrodynamic coefficients were not almost constant throughout different flow velocities, and variation was observed for different hand positions corresponding to different stroke phases. The current study suggests that the realistic variation of both the orientation angles influenced higher values of drag, lift and resultant coefficients and forces.

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Idrobo-Pizo, Gerardo Antonio, José Maurício S. T. Motta et Renato Coral Sampaio. « A Calibration Method for a Laser Triangulation Scanner Mounted on a Robot Arm for Surface Mapping ». Sensors 19, n^o 8 (14 avril 2019) : 1783. http://dx.doi.org/10.3390/s19081783.

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This paper presents and discusses a method to calibrate a specially built laser triangulation sensor to scan and map the surface of hydraulic turbine blades and to assign 3D coordinates to a dedicated robot to repair, by welding in layers, the damage on blades eroded by cavitation pitting and/or cracks produced by cyclic loading. Due to the large nonlinearities present in a camera and laser diodes, large range distances become difficult to measure with high precision. Aiming to improve the precision and accuracy of the range measurement sensor based on laser triangulation, a calibration model is proposed that involves the parameters of the camera, lens, laser positions, and sensor position on the robot arm related to the robot base to find the best accuracy in the distance range of the application. The developed sensor is composed of a CMOS camera and two laser diodes that project light lines onto the blade surface and needs image processing to find the 3D coordinates. The distances vary from 250 to 650 mm and the accuracy obtained within the distance range is below 1 mm. The calibration process needs a previous camera calibration and special calibration boards to calculate the correct distance between the laser diodes and the camera. The sensor position fixed on the robot arm is found by moving the robot to selected positions. The experimental procedures show the success of the calibration scheme.

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Sullivan, Jaron P., Brian A. Warme et Brian R. Wolf. « Use of an O-arm intraoperative computed tomography scanner for closed reduction of posterior sternoclavicular dislocations ». Journal of Shoulder and Elbow Surgery 21, n^o 3 (mars 2012) : e17-e20. http://dx.doi.org/10.1016/j.jse.2011.07.015.

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Baron, Jana, Simon Hazubski et Andreas Otte. « 3D Multi-Material Printing of an Anthropomorphic, Personalized Replacement Hand for Use in Neuroprosthetics Using 3D Scanning and Computer-Aided Design : First Proof-of-Technical-Concept Study ». Prosthesis 2, n^o 4 (18 décembre 2020) : 362–70. http://dx.doi.org/10.3390/prosthesis2040034.

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Background: This paper presents a novel approach for a hand prosthesis consisting of a flexible, anthropomorphic, 3D-printed replacement hand combined with a commercially available motorized orthosis that allows gripping. Methods: A 3D light scanner was used to produce a personalized replacement hand. The wrist of the replacement hand was printed of rigid material; the rest of the hand was printed of flexible material. A standard arm liner was used to enable the user’s arm stump to be connected to the replacement hand. With computer-aided design, two different concepts were developed for the scanned hand model: In the first concept, the replacement hand was attached to the arm liner with a screw. The second concept involved attaching with a commercially available fastening system; furthermore, a skeleton was designed that was located within the flexible part of the replacement hand. Results: 3D-multi-material printing of the two different hands was unproblematic and inexpensive. The printed hands had approximately the weight of the real hand. When testing the replacement hands with the orthosis it was possible to prove a convincing everyday functionality. For example, it was possible to grip and lift a 1-L water bottle. In addition, a pen could be held, making writing possible. Conclusions: This first proof-of-concept study encourages further testing with users.

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Hardy, W., J. Jasko et R. Bogan. « 0689 Use Of An Automated Scanning System To Select A Patient Interface ». Sleep 43, Supplement_1 (avril 2020) : A263. http://dx.doi.org/10.1093/sleep/zsaa056.685.

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Abstract Introduction There is no universal process for selecting mask style, size, and fit, and there is considerable variance in clinician and patient mask preference and patient anatomy. Poor mask fit may negatively affect adherence. A three-dimensional (3D) facial scanner and proprietary analytical software were developed to bring efficiencies to mask selection. This study explored the impact of that system on initial mask success compared to standard practice. Methods This was an open-label, randomized-controlled study. Participants provided written informed consent. 3D Scanner Arm (3DA): Participants answered questions about sleeping habits then had 3D facial images taken. Proprietary software recommended a hierarchy of up to four Philips Respironics masks and sizes. Traditional Fitting Arm (TFA): A designated clinician selected and fit masks using their standard methods. Mask selection was assessed by applying therapy and soliciting patient and clinician feedback. Mask refits and adherence were tracked through 90 days. Five sleep centers recruited 115 participants into the 3DA (61 males, 51.1±13.4 years, BMI 35.2±7.0, diagnostic AHI 26.2±21.9) and 123 into the TFA (79 males, 51.1±11.9 years, BMI 35±7.9, diagnostic AHI 26.9±22.6). Results A significantly higher percentage of 3DA patients required only one mask fitting (with no refits) compared to TFA during the initial setup (89.6% vs. 54.5%, p<0.001) and through 90 days (62.6% vs 37.4%, p<0.001). 3DA subjectively rated confidence in and satisfaction with the scanner-selected mask significantly higher than TFA. Mask leak was lower in the 3DA compared to TFA (29.4±10.6 vs 32.3±11.4 L/M, p= 0.043). The CMS adherence rate tended to favor 3DA vs. TFA (66.7% vs. 55.3, p=0.083). There were no significant differences in AHI or other adherence metrics. Conclusion The 3D scanner system was successful in mask selection with lower mask leak and greater patient satisfaction and confidence. This tool may bring about operational efficiencies to the mask selection process. Support This study was sponsored by Philips Respironics

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Coste, C., Y. Asloum, P. S. Marcheix, P. Dijoux, J. L. Charissoux et C. Mabit. « Vissage iliosacré percutané des lésions instables de l’anneau pelvien : intérêt de la navigation sous scanner (O-ARM) ». Revue de Chirurgie Orthopédique et Traumatologique 99, n^o 4 (juin 2013) : S151—S157. http://dx.doi.org/10.1016/j.rcot.2013.03.003.

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Unger, Michael, Johann Berger, Bjoern Gerold et Andreas Melzer. « Robot-assisted Ultrasound-guided Tracking of Anatomical Structures for the Application of Focused Ultrasound ». Current Directions in Biomedical Engineering 6, n^o 3 (1 septembre 2020) : 123–26. http://dx.doi.org/10.1515/cdbme-2020-3032.

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AbstractHigh intensity focused ultrasound is used as a surgical tool to treat completely non-invasively several diseases. Examples of clinical applications are uterine fibroids, prostate cancer, thyroid nodules, and varicose veins. Precise targeting is key for improving the treatment outcome. A method for an automated, robot-assisted tracking system was developed and evaluated. A wireless ultrasound scanner was used to acquire images of the target, in this case, a blood vessel. The active contour approach by Chan and Vese was used to segment and track while moving the scanner along the target structure with a collaborative robotic arm. The performance was assessed using a custom made Agar phantom. The mean tracking error, which is defined as the remaining distance of the lesion to the images’ centre line, was 0.27 mm ± 0.18 mm.

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Choksi, Ankur, Benjamin Press, Cayce Nawaf, Shannon Longyear, Marc Ferrante et Thomas V. Martin. « The Intraoperative Use of a Portable Cone-Beam Computed Tomography System for the Diagnosis of Intraperitoneal Bladder Perforation ». Case Reports in Urology 2021 (23 septembre 2021) : 1–4. http://dx.doi.org/10.1155/2021/2060572.

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Background. Intraoperative imaging for endourologic procedures is generally limited to single-plane fluoroscopic X-ray. The O-arm™ is a mobile cone-bean CT scanner that may have applications in urologic surgeries. Case Presentation. We present a case of an 85-year-old male with radiation cystitis and recurrent gross hematuria who was identified to have a bladder perforation on cystoscopy during emergent clot evacuation. Single-view fluoroscopic evaluation was inconclusive as to whether an intraperitoneal bladder perforation occurred. A portable cone-beam CT scan was used to acquire a 3-D CT cystogram, which demonstrated intraperitoneal contrast extravasation, confirming the diagnosis of an intraperitoneal bladder perforation. Conclusion. We report the first use of a portable cone-beam CT scanner to perform an intraoperative CT cystogram to diagnose an intraperitoneal bladder perforation and guide surgical management.

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Pfaff, Johannes, Christian Herweh, Mirko Pham, Silvia Schönenberger, Julian Bösel, Peter A. Ringleb, Sabine Heiland, Martin Bendszus et Markus Möhlenbruch. « Mechanical thrombectomy using a combined CT/C-arm X-ray system ». Journal of NeuroInterventional Surgery 8, n^o 6 (2 mai 2015) : 621–25. http://dx.doi.org/10.1136/neurintsurg-2015-011744.

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BackgroundMechanical thrombectomy (MT) using stent-retrievers has been proven to be a safe and effective treatment in acute ischemic stroke (AIS), particularly in large vessel occlusion. Other than patient characteristics, time to recanalization is the most important factor linked to outcome. MT is usually performed in a dedicated angiography suite using a floor- and/or ceiling-mounted biplane angiographic system. Here we report our first experience of MT with a new combined CT and mobile C-arm X-ray device setup.MethodsPatients with AIS underwent stroke imaging (non-contrast enhanced CT, CT perfusion, and CT angiography) using a commercially available 64-slice CT scanner which was modified for combined use with a C-arm system. In patients with large vessel occlusion, MT was conducted without further patient transfer within the CT imaging suite using a mobile C-arm X-ray device equipped with a 30×30 cm (12×12 inch), 1.5×1.5 k full-view flat detector which was positioned between the gantry and patient table. The safety and feasibility of this new system was assessed in preliminary patients.ResultsAngiographic imaging quality of the mobile C-arm was feasible and satisfactory for diagnostic angiography and MT. Using this setup, time between stroke imaging and groin puncture (picture-to-puncture time) was reduced by up to 35 min (including time for preparation of the patient such as intubation).ConclusionsMT using a combined CT/C-arm system is safe and feasible. The potential advantages, particularly time saving and ensuing improvement in patient outcome, need to be assessed in a larger study.

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Helal, Eman, Ahmed M. Esmat et Sherihan M. Eissa. « AMOUNT OF BONE LOSS AND DIGITAL OCCLUSAL ANALYSIS OF DIFFERENT ATTACHMENT DESIGNS IN BILATERAL DISTAL EXTENSION PARTIAL DENTURE CASES ». International Journal of Advanced Research 8, n^o 12 (31 décembre 2020) : 431–38. http://dx.doi.org/10.21474/ijar01/12166.

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Background: OT unilateral extra-coronal attachmentconsidered as one of the best choices for distal extension partially edentulous cases. Aim: Comparing OT unilateral extra-coronal attachment with modified OT unilateral extra-coronal attachment RPDs with bracing arm regardingamount of bone loss and occlusal load (using T-scan system). Methods: Ten patients have missing bilateral mandibular molars teeth were treated according to split-mouth design using protocol A (OT unilateral extra-coronal attachment) and protocol B (modified OT unilateral extra-coronal attachment with a bracing arm). Amount of bone loss was evaluated radiographically at time of denture insertion, 3months, 6month, 9months, 12month and 18 months after denture delivery to measure the bone height changes. Also, occlusal load was evaluated using T-scanner (Digital occlusal analysis). Results: Regarding bone loss: Protocol B was significantly lower than protocol A after 6 and 12 months, while in occlusal load analysis Protocol B was insignificantly lower than protocol A. Conclusion: Less vertical bone height resorption and less occlusal forces in bracing side (OT unilateral extra-coronal attachment RPDs with a bracing arm) when compared with the non-bracing side.

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Whitman, John, Matthew P. Fronheiser, Nikolas M. Ivancevich et Stephen W. Smith. « Autonomous Surgical Robotics Using 3-D Ultrasound Guidance : Feasibility Study ». Ultrasonic Imaging 29, n^o 4 (octobre 2007) : 213–19. http://dx.doi.org/10.1177/016173460702900402.

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The goal of this study was to test the feasibility of using a real-time 3D (RT3D) ultrasound scanner with a transthoracic matrix array transducer probe to guide an autonomous surgical robot. Employing a fiducial alignment mark on the transducer to orient the robot's frame of reference and using simple thresholding algorithms to segment the 3D images, we tested the accuracy of using the scanner to automatically direct a robot arm that touched two needle tips together within a water tank. RMS measurement error was 3.8% or 1.58 mm for an average path length of 41 mm. Using these same techniques, the autonomous robot also performed simulated needle biopsies of a cyst-like lesion in a tissue phantom. This feasibility study shows the potential for 3D ultrasound guidance of an autonomous surgical robot for simple interventional tasks, including lesion biopsy and foreign body removal.

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Pujeri, Prabhakar, et Sanket S. Naik Dessai. « Customization of GPRS, and Wi-Fi device drivers for PXA270 of Linux OS based barcode scanner ». International Journal of Reconfigurable and Embedded Systems (IJRES) 11, n^o 1 (1 mars 2022) : 84. http://dx.doi.org/10.11591/ijres.v11.i1.pp84-92.

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To access any device, it is necessary to have an access point. A device driver is an entry point to access a device. This project is aimed to customize the Wi-Fi and general packet radio service (GPRS) device drivers in Linux OS for PXA270 (Intel Xscale ARM processor). Customizing a device driver is a special way of designing software that can be more easily ported from one architecture to another without rewriting it from scratch. The paper is discussing about the customisation of Wi-Fi and GPRS device driver in Linux OS for PXA270 (Intel Xscale ARM processor). To develop a device driver, it is necessary to understand the processor architecture and Linux kernel internals and other design constraints. Since dynamically loaded driver module is attached to the existing kernel, and any error in the driver will crash the entire system. Resource allocation and implementation for a device is one of the main concerns for device driver developers. The device resources are input/output, memory, IRQs and ports. The required toolchain to build the cross-complier for the Intel Xscale ARM processor was built on Linux platform. The customised device drivers of Wi-Fi, and GPRS was customised, and the customised images are made to port for PXA270 processor architecture on EMX-270 board. With all the supporting parameters the kernel images with drivers are build and ported efficiently. Also, a successful verification and testing had been performed for their functionalities.

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Favero, Riccardo, Andrea Volpato, Maurizio De Francesco, Adolfo Di Fiore, Riccardo Guazzo et Lorenzo Favero. « Accuracy of 3D digital modeling of dental arches ». Dental Press Journal of Orthodontics 24, n^o 1 (février 2019) : 038e1–037e7. http://dx.doi.org/10.1590/2177-6709.24.1.38.e1-7.onl.

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ABSTRACT Objective: The aim of the study was to verify and compare the accuracy of full-arch digital impressions obtained using two intraoral scanners and three scanning methodologies. Methods: A resin model created with dental 3-D printing was scanned by a reference scanner (Zfx Evolution - Zimmer Biomet, Palm Beach Gardens, FL) in order to obtain a 3D reference; the same resin model was then scanned with two different intraoral scanners (Zfx IntraScan and Carestream 3600 - CS 3600®, Carestream, Rochester, NY, USA) using: Technique A (from tooth #27 up to tooth #17); Technique B (from tooth #11 up to tooth #17 and then from tooth #21 up to tooth #27) and Technique C (from tooth #22 up to tooth #17, and then from tooth #12 up to tooth #27 - the MeshLab software v. 1.3.3 was then used to match the two scans). The scans obtained were superimposed over the reference scan by means of a software, and the volumetric discrepancies were calculated. Results: The mean results for the Zfx Intrascan scanner were: Technique A = 302.47 ± 37.42 µm; Technique B = 180.45 ± 29.86 µm; Technique C = 147.34 ± 28.23 µm. The mean results for the Carestream 3600 scanner were: Technique A = 303.59 ± 40.20 µm; Technique B = 181.53 ± 29.61 µm; Technique C = 142.28 ± 35.33 µm. Technique C, used by both scanners, produced less volumetric discrepancies compared to the other techniques. Conclusions: The scanning technique had a statistically significant effect on the quality of the scan (p< 0.0001), whereas the scanner did not present any significant influence (p= 0.91).

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Thomas, Hywel R. « Peter Neil Temple Wells CBE. 19 May 1936—22 April 2017 ». Biographical Memoirs of Fellows of the Royal Society 66 (13 février 2019) : 463–77. http://dx.doi.org/10.1098/rsbm.2018.0022.

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Peter Wells will be remembered internationally for his many outstanding contributions in the field of medical ultrasound. He pioneered the development of non-invasive imaging techniques in the development of ultrasonics as a diagnostic and surgical tool. He was the originator and developer of instruments for ultrasonic surgery and ultrasonic power measurement, as well as the two-dimensional, articulated-arm ultrasonic general purpose scanner and the water-immersion ultrasonic breast scanner. He demonstrated ultrasonic-pulsed Doppler range-gating, and was the discoverer of the ultrasonic Doppler signal characteristic of malignant tumour neovascularization. He investigated ultrasonic bioeffects and formulated ultrasonic safety guidelines and conditions for prudent use of ultrasonic diagnosis. His outstanding and sustained achievements in the medical applications of ultrasound extend continuously from the 1960s until a few days before his death at the age of 80. Anyone who has ever benefited from an ultrasound procedure owes a debt of gratitude to Peter Wells.

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Sufianov, A. A., V. I. Manashchuk, D. N. Nabiev, A. G. Shapkin, M. K. Zaytsev, G. E. Tebloev, A. A. X Al Zahrani, R. S. Talybov et H. L. Abril Arenas. « Surgical treatment of patients with primary and metastatic spinal tumor with use of the O-Arm intraoperative portable computed tomography scanner ». Russian journal of neurosurgery 21, n^o 4 (21 décembre 2019) : 39–49. http://dx.doi.org/10.17650/1683-3295-2019-21-4-39-49.

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The study objective is to demonstrate our experience of employment of O-Arm intraoperative portable сomputed tomography scanner combined with navigation system Stealth Station Treon Plus (Medtronic Navigation) during decompressive-stabilizing surgeries for patients with primary and metastatic spinal tumors.Materials and methods. We have reviewed results of surgical treatment of 44 patients (24 males and 20 females, average age is 54.3 ± 1.8), who were hospitalized and operated in the department of spinal neurosurgery in Federal Centre of Neurosurgery (Tyumen). All surgeries were performed by one surgical team in the period of April 2011 to June 2017. All patients underwent full clinical examination according to diagnostic algorithm, including assessment of general condition, degree of bone and visceral dissemination, neurological status, quality of life, pain syndrome intensity. The most common cause of vertebral lesions was plasma cell myeloma (15 patients, 34.1 %), metastatic spinal lesions (12 patients, 27.3 %). Patients were subjected to posterior decompression and stabilization with total and subtotal excision of mass lesions. Assessment of degree of decompression and transpedicular fixation were carried out visually using O-Arm combined with navigation station.Results. In 6 to 12 months after surgery 79.5 % of patients demonstrated significant improvement of neurological status, specifically a decrease of conduction and sensory disorders. Degree of pain syndrome was reduced by 3.6 times. Using O-Arm combined with navigation station we placed screws adequately in 99.6 % of the cases. The main technical problem that occurred during the surgery was the failure of navigation system caused by: defect of reflective spheres, distant installation and shift of referential frame, aging of Jamshidi needle, malfunction of navigation camera, failure of data transfer from navigation station.Conclusion. The use of O-Arm combined with navigation station for decompressive and stabilizing surgeries in patients with spine and spinal cord tumors let us perform surgeries with 3D control and navigation, conduct surgeries in areas where it is hard to determine surgical landmarks, ensure precision of transpedicular screw implantation, accomplish total resection of mass lesions with minimal blood loss and less aggressive surgical intervention and properly decompress the spinal canal which, eventually, result in positive anatomical and functional characteristics, and contribute to good general outcome of surgical intervention.Conflict of interest. The authors declare no conflict of interest.Informed consent. All patients gave written informed consent to participate in the study and to the publication of their data.

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Cau, Nicola, Manuela Galli, Veronica Cimolin, Marta Aranci, Augusto Caraceni et Augusta Balzarini. « Comparative study between circumferential method and laser scanner 3D method for the evaluation of arm volume in healthy subjects ». Journal of Vascular Surgery : Venous and Lymphatic Disorders 4, n^o 1 (janvier 2016) : 64–72. http://dx.doi.org/10.1016/j.jvsv.2015.05.005.

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Park, Sang Wook, Hee Young Maeng et Ju Wook Park. « Optimal Design and Structural Precision Analysis for a Spherical Coordinate System 3D Scanner Guiding Device ». Applied Mechanics and Materials 705 (décembre 2014) : 164–68. http://dx.doi.org/10.4028/www.scientific.net/amm.705.164.

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Recently, automatic 3D scanning devices are commonly researched and developed for better productivity of the reverse engineering fields. In this paper, a 3D scanner utilizing a spherical coordinate system was designed and analyzed using FEM analysis. The system was designed for optimal performance, high precision, minimal deflection, and speed of data collection. FEM analysis allowed us to properly design the system to achieve these goals, with focus on the deflection of the cantilever arm. Results of the FEM analysis and figures showing the apparatus design are provided. Successive prototypes are shown to increase in overall performance and reliability through improved design and analysis.

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Přibil, Jiří, Anna Přibilová et Ivan Frollo. « Comparison of Three Prototypes of PPG Sensors for Continual Real-Time Measurement in Weak Magnetic Field ». Sensors 22, n^o 10 (16 mai 2022) : 3769. http://dx.doi.org/10.3390/s22103769.

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This paper is focused on investigation of three developed prototypes of sensors based on the photoplethysmography (PPG) principle for continual measurement of the PPG signal in the magnetic field environment with the inherent radiofrequency and electromagnetic disturbance. The tested prototypes differ in the used optical part of the PPG sensor and their working mode, control unit, power supply, and applied Bluetooth (BT) communication methods. The main aim of the current work was motivated by finding suitable and universal parameter settings for PPG signal real-time recording in different working mode conditions. Comparative measurements in laboratory conditions by certified commercial pulse oximeter and blood pressure monitor (BPM) devices show good stability and proper accuracy of finally determined heart rate values. The supplementary investigation certifies the necessity of the placement of the pressure cuff of the BPM device on the opposite arm than the tested PPG sensor. Measurement experiments inside the scanning area of the running weak field magnetic resonance scanner verify proper function and practical usability of sensed PPG signals for further processing and analysis in all three prototype cases. Additional testing shows that the BT transmission in the scanning area has no visible influence on the quality of the finally obtained scanner images.

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Arreeras, Tosporn, Mikiharu Arimura, Takumi Asada et Saharat Arreeras. « Association Rule Mining Tourist-Attractive Destinations for the Sustainable Development of a Large Tourism Area in Hokkaido Using Wi-Fi Tracking Data ». Sustainability 11, n^o 14 (22 juillet 2019) : 3967. http://dx.doi.org/10.3390/su11143967.

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The rise of radiofrequency scanner technology has led to its potential application in the observation of people’s movements. This study used a Wi-Fi scanner device to track tourists’ traveling behavior in Hokkaido’s tourism area, which occupies a large region that features a unique natural landscape. Inbound tourists have significantly increased in recent years; thus, tourism’s sustainability is considered to be important for maintaining the tourism atmosphere in the long term. Using internet-enabled technology to conduct extensive area surveys can overcome the limitations imposed by conventional methods. This study aims to use digital footprint data to describe and understand traveler mobility in a large tourism area in Hokkaido. Association rule mining (ARM)—a machine learning methodology—was performed on a large dataset of transactions to identify the rules that link destinations visited by tourists. This process resulted in the discovery of traveling patterns that revealed the association rules between destinations, and the attractiveness of the destinations was scored on the basis of visiting frequency, with both inbound and outbound movements considered. A visualization method was used to illustrate the relationships between destinations and simplify the mathematical descriptions of traveler mobility in an attractive tourism area. Hence, mining the attractiveness of destinations in a large tourism area using an ARM method integrated with a Wi-Fi mobility tracking approach can provide accurate information that forms a basis for developing sustainable destination management and tourism policies.

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Tumino, Davide, Tommaso Ingrassia, Vincenzo Nigrelli et Giovan Battista Trinca. « Redesign of a Reverse Shoulder Prosthesis : Kinematic and Mechanical Study ». Applied Mechanics and Materials 670-671 (octobre 2014) : 847–51. http://dx.doi.org/10.4028/www.scientific.net/amm.670-671.847.

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In this work a commercial reverse shoulder prosthesis has been redesigned to improve performances in terms of range of movements of the implant and stability to dislocation. A kinematic and mechanic study has been performed using a realistic solid model of the prothesised shoulder: in particular, all the components of the prosthesis have been acquired via a 3D laser scanner and inserted in a virtual humerus-glenoid system by reproducing the common surgical procedure. The final model has been used to measure the maximum angles of abduction and rotation of the arm and the shear forces that cause dislocation. Modifications proposed to the commercial prosthesis are: a different orientation of the cutting plane of the glenoid component and the interposition of a spacer to move the center of rotation of the arm.

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Nett, Brian E., Beverly Aagaard-Kienitz, Yurdal Serarslan, Mustafa K. Başkaya et Guang-Hong Chen. « A Simple Technique for Interventional Tool Placement Combining Fluoroscopy With Interventional Computed Tomography on a C-Arm System ». Operative Neurosurgery 67, n^o 3 (1 septembre 2010) : ons49—ons57. http://dx.doi.org/10.1227/01.neu.0000382976.18891.50.

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Abstract BACKGROUND: Flat-panel cone-beam computed tomography (FP-CBCT) has recently been introduced as a clinical feature in neuroangiography radiographic C-arm systems. OBJECTIVE: To introduce a method of positioning a surgical tool such as a needle or ablation probe within a target specified by intraoperative FP-CBCT scanning. METHODS: Two human cadaver and 2 porcine cadaver heads were injected with a mixture of silicone and contrast agent to simulate a contrast-enhanced tumor. Preoperative imaging was performed using a standard 1.5-T magnetic resonance imaging scanner. Intraoperative imaging was used to define the needle trajectory on a GE Innova 4100 flat panel-based neuroangiography C-arm system. RESULTS: Using a combination of FP-CBCT and fluoroscopy, a needle was successfully positioned within each of the simulated contrast-enhanced tumors, as verified by subsequent FP-CBCT scans. CONCLUSIONS: This proof-of-concept study demonstrates the potential utility of combining FP-CBCT scanning with fluoroscopy to position surgical tools when stereotactic devices and image-guided surgery systems are not available. However, further work is required to fully characterize the precision and accuracy of the method in a variety of realistic surgical sites.

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Costa, Vitória, António Sérgio Silva, Rosana Costa, Pedro Barreiros, Joana Mendes et José Manuel Mendes. « In Vitro Comparison of Three Intraoral Scanners for Implant—Supported Dental Prostheses ». Dentistry Journal 10, n^o 6 (15 juin 2022) : 112. http://dx.doi.org/10.3390/dj10060112.

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With continuing technological developments, there have been advances in the field of fixed prosthetics, particularly in impression-taking techniques. These technological advances mean that a wide variety of diagnostic and/or rehabilitation possibilities can be explored without the need for physical models. The aim of this study was to evaluate the accuracy of three intraoral scanners used in oral implant rehabilitation using an extraoral scanner as a reference and varying the scanning area. Three models representing different clinical scenarios were scanned 15 times by each intraoral scanner and three times by the extraoral scanner. The readings were analyzed and overlaid using engineering software (Geomagic® Control X software (Artec Europe, Luxembourg)). Statistically significant differences in accuracy were found between the three intraoral scanners, iTero® (Align Technology Inc., San Jose, CA, USA), Medit® (Medit®: Seoul, Korea), and Planmeca® (Planmeca®: Helsinki, Finland). In all clinical scenarios, the iTero® scanner had the best trueness (24.4 μm), followed by the Medit® (26.4 μm) and Planmeca® (42.1 μm). The Medit® showed the best precision (18.00 μm) followed by the iTero® (19.20 μm) and Planmeca® (34.30 μm). We concluded that the iTero® scanner had the highest reproducibility and accuracy in the clinical setting.

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Mukhametzhanov, Khanat, Dulat Mukhametzhanov, Buratay Karibayev, Sholpan Bulekbayeva, Olzhas Bekarisov, Kenzhe Kussainova et Nurzhan Dussenbayev. « The use of an Intraoperative Computed Tomograph with a Navigation Station for Operations on the Spine ». Research Institute of Traumatology and Orthopedics 1, n^o 51 (2020) : 24–39. http://dx.doi.org/10.52889/1684-9280-2020-1-51-24-39.

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The aim of the study: to analyze the results of using an intraoperative computed tomography scanner with a navigation station during spinal operations. Methods. The authors conducted a retrospective and prospective analysis of the results of 350 operations using the image intensifier tube, 390 operations with O arm and 11 operations with O arm and the Stealth-Station navigation station (Medtronic, USA). To the 350 patients operated on using the image intensifier, 1822 screws were implanted, on average 5.2 screws per operation. 117 (6.5%) screws were implanted incorrectly, of which a permissible or clinically insignificant malposition of the screw was noted in 90 (4.9%) patients. Incorrectly installed screws remaining in 27 (1.5%) patients required revision surgery. To 390 patients operated with O arm, 2477 screws were implanted, on average 6.3 screws during one operation. Incorrectly 33 (1.3%) screws were implanted, of which 25 screws were acceptable malposition. Invalid malposition of 8 (0.3%) screws was eliminated during the current operation. Results. Comparative studies of the total number of incorrectly implanted screws during operations using the image intensifier tube and O arm showed that they were more often observed when using the image intensifier tube (p <0.001) and there was no unacceptable malposition of the screws when performing the operation under O arm, since it was diagnosed in time during current operation and eliminated. A total of 66 screws were implanted in 11 patients operated using O arm and the Stealth-Station navigation station, an average of 6 screws during one operation. Inaccurate implantation of screws was not observed in any patient. Conclusions. O-arm with the Stealth-Station navigation station is the most modern method of controlling the correctness of spinal operations when anatomical landmarks are partially invisible - with open operations or invisible at all - with minimally invasive surgical interventions in real time.

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Yao, Xiao Feng, Jian Ping Wang, Dong Ping Li et Tin Ting He. « Preparation and Research of Iatric Fiber with Far Infrared Ray Radiation Function ». Advanced Materials Research 586 (novembre 2012) : 210–14. http://dx.doi.org/10.4028/www.scientific.net/amr.586.210.

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Many kinds of jewelries and ceramic could emit far-infrared rays (FIR) when subjected to the body temperature. Reported works show that FIR have some effects on human body, especially on skin, blood circulation, and skin cell vitalizing. In this study, we tried to use pearl and Panax Notoginseng powder in nanoscale as ingredients to add in viscose fiber and investigate whether this new fiber has benign regulative action on human microcirculation. SEM scanner was used to study the distribution and mean diameter of the particles in fiber. 30 graduates were chosen as subjects and divided into two groups. They used the arm sleeves either impregnated or not impregnated with pearl and Panax Notoginseng powder for 30min/an hour, and were tested the nail-fold microcirculation change. Experimental data showed a much larger improvement of nail-fold microcirculation while using arm sleeves impregnated with pearl and Panax Notoginseng powder than pure cotton arm sleeves. Experimental results are provided to demonstrate the new type iatric fiber with pearl and Panax Notoginseng powder has the capability of biological modulation.

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Donnici, Mario, Giorgia Lupinacci, Paola Nudo, Michele Perrelli et Guido Danieli. « Using Navi-Robot and a CT Scanner to Guide Biopsy Needles ». International Journal of Automation Technology 11, n^o 3 (28 avril 2017) : 450–58. http://dx.doi.org/10.20965/ijat.2017.p0450.

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Purpose of this study was to control the suitability of Navi-Robot, a robotic system developed by our research group, to guide percutaneous needle placement under computed tomography (CT) in order to achieve lower radiation exposure and a shorter procedure. The system consists of a high precision six-degrees-of-freedom self-balanced arm, able to move both in passive and active modes, which allows the physician an accurate needle-insertion. The target and the needle entry points are selected by the surgeon on a desktop computer, that acquires DICOM images from the CT scan, and that, using software developed for this purpose, detects also the position of at least three radio opaque markers placed on the patient or on the stretcher. Once these data are obtained, a new system of reference is established based on the markers position, obtaining the coordinates of target and entry point in the new frame of reference. Going then to touch the tip of the spheres with the tip of the robot end effector in passive mode, and recording their position, the robot learns where the two points of interest are located in its frame of reference. A first test was performed on a Plexiglas board; the accuracy achieved was measured as the distance between the needle tip and the target. The results of the in vitro experiment showed that the system is able to reach the target with an accuracy of 1.2 mm.

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Caruana, Ethan, Carlos Wigderowitz et Fraser Harrold. « Position of the rotator cuff footprint in relation to the centre of rotation of the humeral head ». Shoulder & ; Elbow 11, n^o 1_suppl (22 janvier 2018) : 26–29. http://dx.doi.org/10.1177/1758573217736027.

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Background The objective of the present study was to determine the size and position of the rotator cuff moment arms constructed from the cuff footprints, incident on the line of force acting through the humeral head. Methods Five humeri were dissected, leaving the footprints of the rotator cuff intact. Each of the rotator cuff footprints and the cartilage/calcar interface were digitized and the articular surface was scanned using a high precision surface laser scanner. All of the data were merged into the same coordinate system. The centroid of each cuff footprint, centroid of the articular surface of the humerus (G) and the centroid of the articular surface of the glenoid (P) were calculated. Moment arms were measured as the intersection of a perpendicular line of force from each footprint centroid onto the resultant line of force to the centroid of the Glenoid (P). Results The mean moment arms of the supraspinatus, infraspinatus and subscapularis muscles were incident close to the centroid (G), whereas teres minor was lateral to the centroid, consistently. Conclusions The teres minor moment arm aligned distal to the centroid of the sphere, consistently. The results may provide an understanding of the function of each muscle as a mobilizer or stabilizer of the glenohumeral joint. Further investigation is necessary.

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Kaszuba, Marcin D., Paweł Widomski, Tomasz Kiełczawa et Zbigniew Gronostajski. « The use of a measuring arm with a laser scanner for analysis and support of regenerative surfacing processes of forging dies ». Welding Technology Review 92, n^o 3 (11 avril 2020) : 23–32. http://dx.doi.org/10.26628/wtr.v92i3.1103.

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The article presents the results of research conducted in order to develop the technology of regenerative surfacing of forging dies. The selected example shows how the use of a measuring arm with a laser scanner can be used to support the regeneration process. The tests were conducted in industrial conditions of a forging die. The analysis of the regeneration process was carried out at each of 4 stages: after wear in the forging process, after initial machining, after regenerative surfacing and after final machining. It has been shown that scanning can be used to develop programs for mechanical pre- treatment, to measure the volume of padding welds, to determine the amount of finishing allowance, to verify the effectiveness of the surfacing process and to control the quality of the die before the forging process. The obtained results confirmed the effectiveness of the regeneration carried out. In terms of performance, it has been shown that too much padding weld's material is a machining allowance. For this reason, the treatment is time and energy consuming and about 68% of the padding weld's material is waste or chips. The analysis showed the possibility of saving up to 45% of the weld metal material by using reasonable allowances of smaller thickness. These results indicate the need to modify the regeneration technology and the legitimacy of using robotic surfacing, which can provide greater precision and repeatability in the layingof padding weld’s beads. The next stage of research will be robotization of the analyzed forging die regeneration process using WAAM technology.

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Almeida, Cesar C., Ayse Uzuner et Ron L. Alterman. « Stereotactic Drainage of Brainstem Abscess With the BrainLab Varioguide™ System and the Airo™ Intraoperative CT Scanner : Technical Case Report ». Operative Neurosurgery 14, n^o 4 (12 août 2017) : E46—E50. http://dx.doi.org/10.1093/ons/opx126.

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Abstract BACKGROUND AND IMPORTANCE Stereotactic biopsies or needle aspirations of posterior fossa lesions are technically challenging. Here we report a novel technique for performing these procedures employing the Airo™ intraoperative computed tomographic (CT) scanner and the VarioGuide™ articulated arm (BrainLab, Munich, Germany). CLINICAL PRESENTATION A 62-yr-old woman presented with an irregularly shaped, enhancing lesion of the left pons/middle cerebellar peduncle. Slowed diffusion on magnetic resonance imaging suggested an abscess, but no definitive infectious agent/source could be identified. When the patient deteriorated despite broad-spectrum antibiotic therapy, she was taken to the operating room for stereotactic drainage of the abscess employing the described technique. A specific infectious agent (Eikenella corrodens) was identified from the aspirate, allowing for tailored antibiotic therapy. The procedure was well tolerated and the patient made a full recovery with minimal neurological sequelae. CONCLUSION The combination of the Airo™ intraoperative CT and the Varioguide™ articulated arm allows for safe, accurate, and efficient targeting of posterior fossa lesions.

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Song, Jihu, et Minji Kim. « Accuracy on Scanned Images of Full Arch Models with Orthodontic Brackets by Various Intraoral Scanners in the Presence of Artificial Saliva ». BioMed Research International 2020 (27 février 2020) : 1–8. http://dx.doi.org/10.1155/2020/2920804.

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Aim. This study aims to evaluate the accuracy of scanned images of 4 clinically used intraoral scanners (CS3600, i500, Trios3, Omnicam) when scanning the surface of full arch models with various kinds of orthodontic brackets in the presence of artificial saliva. Materials and Methods. Four study models were prepared; bonded with ceramic, metal, and resin brackets, respectively, and without brackets. Reference images were taken by scanning the models with an industrial scanner. Study models were then applied with an artificial saliva and scanned 10 times, respectively, with the above 4 intraoral scanners. All images were converted to STL file format and analyzed with 3D analysis software. By superimposing with the reference images, mean maximum discrepancy values and mean discrepancy values were collected and compared. For statistical analysis, two-way ANOVA was used. Results. Omnicam (1.247 ± 0.255) showed higher mean maximum discrepancy values. CS3600 (0.758 ± 0.170), Trios3 (0.854 ± 0.166), and i500 (0.975 ± 0.172) performed relatively favourably. Resin (1.119 ± 0.255) and metal (1.086 ± 0.132) brackets showed higher mean maximum discrepancy values. Nonbracket (0.776 ± 0.250) and ceramic bracket (0.853 ± 0.269) models generally showed lower mean maximum discrepancy values in studied scanners. In mean discrepancy values, the difference between scanners was not statistically significant whereas among brackets, resin bracketed models (0.093 ± 0.142) showed the highest value. Conclusion. Intraoral scanners and brackets had significant influences on the scanned images with application of artificial saliva on the study models. It may be expected to have similar outcomes in an intraoral environment. Some data showed the discrepancy values up to about 1.5 mm that would require more caution in using intraoral scanners for production of detailed appliances and records.

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Stangeland, Marcus, Trond Engjom, Martin Mezl, Radovan Jirik, Odd Gilja, Georg Dimcevski et Kim Nylund. « Interobserver Variation of the Bolus-and-Burst Method for Pancreatic Perfusion with Dynamic – Contrast-Enhanced Ultrasound ». Ultrasound International Open 03, n^o 03 (juin 2017) : E99—E106. http://dx.doi.org/10.1055/s-0043-110475.

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Abstract Purpose Dynamic contrast-enhanced ultrasound (DCE-US) can be used for calculating organ perfusion. By combining bolus injection with burst replenishment, the actual mean transit time (MTT) can be estimated. Blood volume (BV) can be obtained by scaling the data to a vessel on the imaging plane. The study aim was to test interobserver agreement for repeated recordings using the same ultrasound scanner and agreement between results on two different scanner systems. Materials and Methods Ten patients under evaluation for exocrine pancreatic failure were included. Each patient was scanned two times on a GE Logiq E9 scanner, by two different observers, and once on a Philips IU22 scanner, after a bolus of 1.5 ml Sonovue. A 60-second recording of contrast enhancement was performed before the burst and the scan continued for another 30 s for reperfusion. We performed data analysis using MATLAB-based DCE-US software. An artery in the same depth as the region of interest (ROI) was used for scaling. The measurements were compared using the intraclass correlation coefficient (ICC) and Bland Altman plots. Results The interobserver agreement on the Logiq E9 for MTT (ICC=0.83, confidence interval (CI) 0.46–0.96) was excellent. There was poor agreement for MTT between the Logiq E9 and the IU22 (ICC=−0.084, CI −0.68–0.58). The interobserver agreement for blood volume measurements was excellent on the Logiq E9 (ICC=0.9286, CI 0.7250–0.98) and between scanners (ICC=0.86, CI=0.50–0.97). Conclusion Interobserver agreement was excellent using the same scanner for both parameters and between scanners for BV, but the comparison between two scanners did not yield acceptable agreement for MTT. This was probably due to incomplete bursting of bubbles in some of the recordings on the IU22.

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Bohnstedt, Bradley N., R. Shane Tubbs et Aaron A. Cohen-Gadol. « The Use of Intraoperative Navigation for Percutaneous Procedures at the Skull Base Including a Difficult-to-Access Foramen Ovale ». Operative Neurosurgery 70, suppl_2 (3 août 2011) : ons177—ons180. http://dx.doi.org/10.1227/neu.0b013e3182309448.

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ABSTRACT BACKGROUND: We describe the use of an intraoperative CT scan obtained using the Medtronic O-arm (Littleton, Massachusetts) for image-guided cannulation of the foramen ovale not previously accessible with the use of fluoroscopy alone. Unlike previously described procedures, this technique does not require placement of an invasive head clamp and may be used with an awake patient. OBJECTIVE: To describe the use of intraoperative neuronavigation for accessing skull base foramina and, specifically, cannulating of the foramen ovale during percutaneous rhizotomy procedures using an intraoperative image guidance CT scanner (Medtronic O-arm, Littleton, Massachusetts). METHODS: A noninvasive Landmark Fess Strap attached to a spine reference frame was applied to the heads of 4 patients who harbored a difficult-to-access foramen ovale. An intraoperative HD3D skull base scan using a Medtronic O-arm was obtained, and Synergy Spine software was used to create 3D reconstructions of the skull base. Using image guidance, we navigated the needle to percutaneously access the foramen ovale by the use of a single tract for successful completion of balloon compression of the trigeminal nerve. RESULTS: All 4 patients (3 females and 1 male; ages 65-75) underwent the procedure with no complications. CONCLUSION: Based on our experience, neuronavigation with the use of intraoperative O-arm CT imaging is useful during these cases.

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Dewey, Rebecca S., Rachel Gomez, Chris Degg, David M. Baguley et Paul M. Glover. « Qualitative and quantitative assessment of magnetic vestibular stimulation in humans ». Journal of Vestibular Research 30, n^o 6 (16 décembre 2020) : 353–61. http://dx.doi.org/10.3233/ves-201538.

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The sensation of phantom motion or exhibition of bodily sway is often reported in the proximity of an MR scanner. It is proposed that the magnetic field stimulates the vestibular system. There are a number of possible mechanisms responsible, and the relative contributions of susceptibility on the otolithic receptors and the Lorentz force on the cupulae have not yet been explored. This exploratory study aims to investigate the impact of being in the proximity of a 7.0 T MR scanner. The modified clinical test of sensory interaction on balance (mCTSIB) was used to qualitatively ascertain whether or not healthy control subjects who passed the mCTSIB in normal conditions 1) experienced subjective sensations of dizziness, vertigo or of leaning or shifting in gravity when in the magnetic field and 2) exhibited visibly increased bodily sway whilst in the magnetic field compared to outside the magnetic field. Condition IV of the mCTSIB was video recorded outside and inside the magnetic field, providing a semi-quantitative measure of sway. For condition IV of the mCTSIB (visual and proprioceptive cues compromised), all seven locations/orientations around the scanner yielded significantly more sway than at baseline (p < 0.01 FDR). A Student’s t-test comparing the RMS velocity of a motion marker on the upper arm during mCTSIB condition IV showed a significant increase in the amount of motion exhibited in the field (T = 2.59; d.f. = 9; p = 0.029) compared to outside the field. This initial study using qualitative measures of sway demonstrates that there is evidence for MR-naïve individuals exhibiting greater sway while performing the mCTSIB in the magnetic field compared to outside the field. Directional polarity of sway was not significant. Future studies of vestibular stimulation by magnetic fields would benefit from the development of a sensitive, objective measure of balance function, which can be performed inside a magnetic field.

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Cau, Nicola, Manuela Galli, Veronica Cimolin, Alida Grossi, Ivan Battarin, Greta Puleo, Augusta Balzarini et Augusto Caraceni. « Quantitative comparison between the laser scanner three-dimensional method and the circumferential method for evaluation of arm volume in patients with lymphedema ». Journal of Vascular Surgery : Venous and Lymphatic Disorders 6, n^o 1 (janvier 2018) : 96–103. http://dx.doi.org/10.1016/j.jvsv.2017.08.014.

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Gronostajski, Zbigniew, Marek Hawryluk, Marcin Kaszuba et Jacek Ziemba. « Application of a measuring arm with an integrated laser scanner in the analysis of the shape changes of forging instrumentation during production ». Eksploatacja i Niezawodnosc - Maintenance and Reliability 18, n^o 2 (20 mars 2016) : 194–200. http://dx.doi.org/10.17531/ein.2016.2.6.

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Lee, Sang J., Soo-Woo Kim, Joshua J. Lee et Chan W. Cheong. « Comparison of Intraoral and Extraoral Digital Scanners : Evaluation of Surface Topography and Precision ». Dentistry Journal 8, n^o 2 (20 mai 2020) : 52. http://dx.doi.org/10.3390/dj8020052.

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The aim of this study was to evaluate the surface topography and the precision measurements of different intraoral and extraoral digital scanners. A reference model of a maxillary arch with four implant analogs was prepared and scanned by three intraoral and two extraoral scanners. The reference model was scanned fifteen times with each digital scanning system, investigating the surface topography and precision measurements for the same-arch and cross-arch measurements. The data was exported to 3D inspection and mesh-processing software (GOM Inspect, Braunschweig, Germany). Statistical analysis was performed using a one-way Analysis of Variance (ANOVA) with the Tukey method for pairwise comparisons. The effect of parameters on generating the surface topography was analyzed by Univariate Linear Regression Analysis. Of the scanner systems evaluated, iTero (IT) exhibited the most number of triangulation points, followed by Trios 3 Shape (TR) and Straumann Cares (SC). There were no significant differences observed in the surface topography when comparing flat and contoured surfaces, the anterior and posterior position, and interproximal areas. For the precision measurement in the same quadrant, no statistical difference was noted between intra- and extraoral scanners. However, the extraoral scanners showed substantially higher precision measurements for the cross-arch measurement. Surface topography did not correlate to precision. Rather, precision correlated with the scanning mechanism. For a quadrant scanning, both intraoral and extraoral scanners are recommended, but extraoral scanners are recommended for a full-arch scanning.

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Rak, Michał, et Eugeniusz Ratajczyk. « Coordinate measuring arms – different methods of points collection ». Mechanik 90, n^o 12 (11 décembre 2017) : 1168–71. http://dx.doi.org/10.17814/mechanik.2017.12.200.

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This paper deals with different methods of points collection using coordinate measuring arm. The research is divided into two parts. The first one is about measuring an aluminum cube with different geometric features with the use of hard probe and laser scanner. For the analysis some features and some resulting parameters were applied, like angle between two planes. As the reference, data from CMM measurements is used due to obtain higher level of accuracy of device. In the second part, a Teflon cube was used for the measurement. As this is a softer material than aluminum, measuring force gives significant impact on the results. To verify this, hard and triggering head was used.

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BUYRUK, H. M., W. P. J. HOLLAND, C. J. SNIJDERS, J. S. LAMÉRIS, E. HOORN, R. STOECKART et H. J. STAM. « Tendon Excursion Measurements With Colour Doppler Imaging ». Journal of Hand Surgery 23, n^o 3 (juin 1998) : 350–53. http://dx.doi.org/10.1016/s0266-7681(98)80056-9.

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We assessed the applicability of tendon excursion measurement by means of Colour Doppler Imaging (CDI) on human specimens, and also assessed the correlation between values measured by Doppler and by displacement meters. Muscles were separately connected to a mass of 1 kg with a steel wire running over a pulley. This weight moved the telescopic end of a digital displacement meter up and down during passive extension and flexion of the fingers. Excursion was measured with a pulsed multi-channel CDI scanner on the same arm. Assessment of finger tendon excursion with CDI correlated well with the mechanical micro displacement meter, the latter being considered the most accurate method in cadaver studies.

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Wakatsuki, S., H. Belrhali, E. P. Mitchell, W. P. Burmeister, S. M. McSweeney, R. Kahn, D. Bourgeois, M. Yao, T. Tomizaki et P. Theveneau. « ID14 `Quadriga', a Beamline for Protein Crystallography at the ESRF ». Journal of Synchrotron Radiation 5, n^o 3 (1 mai 1998) : 215–21. http://dx.doi.org/10.1107/s0909049597018785.

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The ESRF undulator beamline ID14 `Quadriga' is dedicated to monochromatic macromolecular crystallography. Using two undulators with 23 mm and 42 mm periods and a minimum gap of 16 mm installed on a high-β section, it will provide high-brilliance X-ray beams at around 13.5 keV, as well as a wide tuneability between 6.8 and 40 keV. Based on the Troika concept, this beamline has four simultaneously operating experimental stations: three side stations, EH1, EH2 and EH3, using thin diamond crystals, and an end station, EH4, with a fast-scan double-crystal monochromator. Station EH3 has a κ-diffractometer, and an off-line Weissenberg camera with a large 80 × 80 cm active area combined with a 2048 × 2048 CCD detector. During data collection the image plates are placed and removed by a robot located inside the hutch using a cassette system. After data collection the image plates are scanned with an off-line drum scanner. Station EH4 is designed for MAD applications, including Xe K-edge anomalous experiments, and is equipped with a 2048 × 2048 CCD detector on a pseudo 2θ arm. A common graphical user interface and a database will be available to cover all aspects of data collection, including strategy optimization. First results on the performance of the optics elements and initial crystallographic results are presented.

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