Journal articles: 'Human Computational Phantoms'

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Zankl, M., J. Becker, C. Lee, W. E. Bolch, Y. S. Yeom, and C. H. Kim. "Computational phantoms, ICRP/ICRU, and further developments." Annals of the ICRP 47, no. 3-4 (April 13, 2018): 35–44. http://dx.doi.org/10.1177/0146645318756229.

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Phantoms simulating the human body play a central role in radiation dosimetry. The first computational body phantoms were based upon mathematical expressions describing idealised body organs. With the advent of more powerful computers in the 1980s, voxel phantoms have been developed. Being based on three-dimensional images of individuals, they offer a more realistic anatomy. Hence, the International Commission on Radiological Protection (ICRP) decided to construct voxel phantoms representative of the adult Reference Male and Reference Female for the update of organ dose coefficients. Further work on phantom development has focused on phantoms that combine the realism of patient-based voxel phantoms with the flexibility of mathematical phantoms, so-called ‘boundary representation’ (BREP) phantoms. This phantom type has been chosen for the ICRP family of paediatric reference phantoms. Due to the limited voxel resolution of the adult reference computational phantoms, smaller tissues, such as the lens of the eye, skin, and micron-thick target tissues in the respiratory and alimentary tract regions, could not be segmented properly. In this context, ICRP Committee 2 initiated a research project with the goal of producing replicas of the ICRP Publication 110 phantoms in polygon mesh format, including all source and target regions, even those with micron resolution. BREP phantoms of the fetus and the pregnant female at various stages of gestation complete the phantoms available for radiation protection computations.

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Chumak, V., N. Petrenko, O. Bakhanova, V. Voloskyi, and T. Treskunova. "USE OF ANTHROPOMORPHIC HETEROGENEOUS PHYSICAL PHANTOMS FOR VALIDATION OF COMPUTATIONAL DOSIMETRY OF MEDICAL PERSONNEL AND PATIENTS." Проблеми радіаційної медицини та радіобіології = Problems of Radiation Medicine and Radiobiology 25 (2020): 148–76. http://dx.doi.org/10.33145/2304-8336-2020-25-148-176.

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In the dosimetry of ionizing radiation, the phantoms of the human body, which are used as a replacement for the human body in physical measurements and calculations, play an important, but sometimes underestimated, role. There are physical phantoms used directly for measurements, and mathematical phantoms for computational dosimetry. Their complexity varies from simple geometry applied for calibration purposes up to very complex, which simulates in detail the shapes of organs and tissues of the human body. The use of physical anthropomorphic phantoms makes it possible to effectively optimize radiation doses by adjusting the parameters of CT-scanning (computed tomography) in accordance with the characteristics of the patient without compromising image quality. The use of phantoms is an indispensable approach to estimate the actual doses to the organs or to determine the effective dose of workers – values that are regulated, but cannot be directly measured. The article contains an overview of types, designs and the fields of application of anthropomorphic heterogeneous physical phantoms of a human with special emphasis on their use for validation of models and methods of computational dosimetry. Key words: dose, ionizing radiation, physical, mathematical phantoms, computational dosimetry.

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Januszkiewicz, Łukasz, and Sławomir Hausman. "Simplified human phantoms for narrowband and ultra-wideband body area network modelling." COMPEL: The International Journal for Computation and Mathematics in Electrical and Electronic Engineering 34, no. 2 (March 2, 2015): 439–47. http://dx.doi.org/10.1108/compel-10-2014-0292.

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Purpose – The purpose of this paper is to compare the properties of simplified physical and corresponding numerical human body models (phantoms) and verify their applicability to path loss modeling in narrowband and ultra-wideband on-body wireless body area networks (WBANs). One of the models has been proposed by the authors. Design/methodology/approach – Two simplified numerical and two physical phantoms for body area network on-body channel computer simulation and field measurement results are presented and compared. Findings – Computer simulations and measurements which were carried out for the proposed simplified six-cylinder model with various antenna locations lead to the general conclusion that the proposed phantom can be successfully used for experimental investigation and testing of on-body WBANs both in ISM and UWB IEEE 802.15.6 frequency bands. Research limitations/implications – Usage of the proposed phantoms for the simulation/measurement of the specific absorption rate and for off-body channels are not within the scope of this paper. Practical implications – The proposed simplified phantom can be easily made with a low cost in other laboratories and be used both for research and development of WBAN technologies. The model is most suitable for wearable antenna radiation pattern simulation and measurement. Social implications – Presented results facilitate applications of WBANs in medicine and health monitoring. Originality/value – A new six-cylinder phantom has been proposed. The proposed simplified phantom can be easily made with a low cost in other laboratories and be used both for research and development of WBAN technologies.

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Erickson, David W., Jered R. Wells, Gregory M. Sturgeon, Ehsan Samei, James T. Dobbins, W. Paul Segars, and Joseph Y. Lo. "Population of 224 realistic human subject-based computational breast phantoms." Medical Physics 43, no. 1 (December 17, 2015): 23–32. http://dx.doi.org/10.1118/1.4937597.

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Ortego-Isasa, Iñaki, Ainhoa Rezola, Yue Gao, Xiaodong Chen, and Daniel Valderas. "Minimum Representative Human Body Model Size Determination for Link Budget Calculation in Implanted Medical Devices." Applied Sciences 11, no. 13 (June 29, 2021): 6032. http://dx.doi.org/10.3390/app11136032.

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In this work, the optimum homogeneous phantom size for an equivalent whole-body electromagnetic (EM) modeling is calculated. This will enable the simple characterization of plane wave EM attenuation and far-field link budgets in Active Medical Implant (AMI) applications in the core region of the body for Industrial, Scientific, Medical and MedRadio frequency bands. A computational analysis is done to determine the optimum size in which a minimum phantom size reliably represents a whole-body situation for the corresponding frequency of operation, saving computer and laboratory resources. After the definition of a converge criterion, the computed minimum phantom size for subcutaneous applications, 0–10 mm insertion depth, is 355 × 160 × 255 mm3 for 402 MHz and 868 MHz and a cube with a side of 100 mm and 50 mm for 2.45 GHz and 5.8 GHz, respectively. For deep AMI applications, 10–50 mm insertion depth, the dimensions are 355 × 260 × 255 mm3 for 402 MHz and 868 MHz, and a cube with a side of 200 mm and 150 mm for 2.45 GHz and 5.8 GHz, respectively. A significant reduction in both computational and manufacturing resources for phantom development is thereby achieved. The verification of the model is performed by field measurements in phantoms made by aqueous solutions with sugar.

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Yeom, Yeon Soo, Han Sung Kim, Thang Tat Nguyen, Chansoo Choi, Min Cheol Han, Chan Hyeong Kim, Jai Ki Lee, et al. "New small-intestine modeling method for surface-based computational human phantoms." Journal of Radiological Protection 36, no. 2 (March 23, 2016): 230–45. http://dx.doi.org/10.1088/0952-4746/36/2/230.

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Maynard, M., J. Geyer, J. Aris, R. Shifrin, and W. Bolch. "SU-GG-I-51: Hybrid Computational Phantoms of the Developing Human Fetus." Medical Physics 37, no. 6Part3 (June 2010): 3113. http://dx.doi.org/10.1118/1.3468084.

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Lee, Choonsik, Andreu Badal, Yeon Soo Yeom, Keith T. Griffin, and Dayton McMillan. "Dosimetric impact of voxel resolutions of computational human phantoms for external photon exposure." Biomedical Physics & Engineering Express 5, no. 6 (September 23, 2019): 065002. http://dx.doi.org/10.1088/2057-1976/ab2850.

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Rispoli, Joseph V., Steven M. Wright, Craig R. Malloy, and Mary P. McDougall. "Automated modification and fusion of voxel models to construct body phantoms with heterogeneous breast tissue: Application to MRI simulations." Journal of Biomedical Graphics and Computing 7, no. 1 (February 26, 2017): 1. http://dx.doi.org/10.5430/jbgc.v7n1p1.

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Background: Human voxel models incorporating detailed anatomical features are vital tools for the computational evaluation of electromagnetic (EM) fields within the body. Besides whole-body human voxel models, phantoms representing smaller heterogeneous anatomical features are often employed; for example, localized breast voxel models incorporating fatty and fibroglandular tissues have been developed for a variety of EM applications including mammography simulation and dosimetry, magnetic resonance imaging (MRI), and ultra-wideband microwave imaging. However, considering wavelength effects, electromagnetic modeling of the breast at sub-microwave frequencies necessitates detailed breast phantoms in conjunction with whole-body voxel models.Methods: Heterogeneous breast phantoms are sized to fit within radiofrequency coil hardware, modified by voxel-wise extrusion, and fused to whole-body models using voxel-wise, tissue-dependent logical operators. To illustrate the utility of this method, finite-difference time-domain simulations are performed using a whole-body model integrated with a variety of available breast phantoms spanning the standard four tissue density classifications representing the majority of the population.Results: The software library uses a combination of voxel operations to seamlessly size, modify, and fuse eleven breast phantoms to whole-body voxel models. The software is publicly available on GitHub and is linked to the file exchange at MATLAB R Central. Simulations confirm the proportions of fatty and fibroglandular tissues in breast phantoms have significant yet predictable implications on projected power deposition in tissue.Conclusions: Breast phantoms may be modified and fused to whole-body voxel models using the software presented in this work; user considerations for the open-source software and resultant phantoms are discussed. Furthermore, results indicate simulating breast models as predominantly fatty tissue can considerably underestimate the potential for tissue heating in women with substantial fibroglandular tissue.

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Kainz, Wolfgang, Esra Neufeld, Wesley E. Bolch, Christian G. Graff, Chan Hyeong Kim, Niels Kuster, Bryn Lloyd, et al. "Advances in Computational Human Phantoms and Their Applications in Biomedical Engineering—A Topical Review." IEEE Transactions on Radiation and Plasma Medical Sciences 3, no. 1 (January 2019): 1–23. http://dx.doi.org/10.1109/trpms.2018.2883437.

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Lee, Choonsik, Gleb A. Kuzmin, Jinyong Bae, Jianhua Yao, Elizabeth Mosher, and Les R. Folio. "Automatic Mapping of CT Scan Locations on Computational Human Phantoms for Organ Dose Estimation." Journal of Digital Imaging 32, no. 1 (September 5, 2018): 175–82. http://dx.doi.org/10.1007/s10278-018-0119-2.

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Maynard, Matthew R., John W. Geyer, John P. Aris, Roger Y. Shifrin, and Wesley Bolch. "The UF family of hybrid phantoms of the developing human fetus for computational radiation dosimetry." Physics in Medicine and Biology 56, no. 15 (July 15, 2011): 4839–79. http://dx.doi.org/10.1088/0031-9155/56/15/014.

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Han, Haegin, Yeon Soo Yeom, Chansoo Choi, Sungho Moon, Bangho Shin, Sangseok Ha, and Chan Hyeong Kim. "POLY2TET: a computer program for conversion of computational human phantoms from polygonal mesh to tetrahedral mesh." Journal of Radiological Protection 40, no. 4 (September 23, 2020): 962–79. http://dx.doi.org/10.1088/1361-6498/abb360.

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Griffin, Keith T., Matthew M. Mille, Christopher Pelletier, Mahesh Gopalakrishnan, Jae Won Jung, Choonik Lee, John Kalapurakal, Anil Pyakuryal, and Choonsik Lee. "Conversion of computational human phantoms into DICOM-RT for normal tissue dose assessment in radiotherapy patients." Physics in Medicine & Biology 64, no. 13 (July 5, 2019): 13NT02. http://dx.doi.org/10.1088/1361-6560/ab2670.

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Chanda, Arnab, Vinu Unnikrishnan, Zachary Flynn, and Kim Lackey. "Experimental study on tissue phantoms to understand the effect of injury and suturing on human skin mechanical properties." Proceedings of the Institution of Mechanical Engineers, Part H: Journal of Engineering in Medicine 231, no. 1 (December 21, 2016): 80–91. http://dx.doi.org/10.1177/0954411916679438.

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Skin injuries are the most common type of injuries occurring in day-to-day life. A skin injury usually manifests itself in the form of a wound or a cut. While a shallow wound may heal by itself within a short time, deep wounds require surgical interventions such as suturing for timely healing. To date, suturing practices are based on a surgeon’s experience and may vary widely from one situation to another. Understanding the mechanics of wound closure and suturing of the skin is crucial to improve clinical suturing practices and also to plan automated robotic surgeries. In the literature, phenomenological two-dimensional computational skin models have been developed to study the mechanics of wound closure. Additionally, the effect of skin pre-stress (due to the natural tension of the skin) on wound closure mechanics has been studied. However, in most of these analyses, idealistic two-dimensional skin geometries, materials and loads have been assumed, which are far from reality, and would clearly generate inaccurate quantitative results. In this work, for the first time, a biofidelic human skin tissue phantom was developed using a two-part silicone material. A wound was created on the phantom material and sutures were placed to close the wound. Uniaxial mechanical tests were carried out on the phantom specimens to study the effect of varying wound size, quantity, suture and pre-stress on the mechanical behavior of human skin. Also, the average mechanical behavior of the human skin surrogate was characterized using hyperelastic material models, in the presence of a wound and sutures. To date, such a robust experimental study on the effect of injury and sutures on human skin mechanics has not been attempted. The results of this novel investigation will provide important guidelines for surgical planning and validation of results from computational models in the future.

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Campana, Luca G., Paolo Di Barba, Fabrizio Dughiero, Michele Forzan, Maria Evelina Mognaschi, Rudy Rizzo, and Elisabetta Sieni. "Non-parallellism of needles in electroporation: 3D computational model and experimental analysis." COMPEL - The international journal for computation and mathematics in electrical and electronic engineering 38, no. 1 (January 7, 2019): 348–61. http://dx.doi.org/10.1108/compel-04-2018-0189.

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PurposeIn electrochemotherapy, flexible electrodes, composed by an array of needles, are applied to human tissues to treat large surface tumors. The positioning of the needles in the tissue depends on the surface curvature. The parallel needle case is preferred, as their relative inclinations strongly affect the actual distribution of electric field. Nevertheless, in some case, small inclinations are unavoidable. The purpose of this paper is to study the electric field distribution for non-parallel needles.Design/methodology/approachThe effect of electrode position is evaluated systematically by means of numerical models and experiments on phantoms for two different angles (5° and 30°) and compared with the case of parallel needles. Potato model was used as phantom, as this tissue becomes dark after few hours from electroporation. The electroporation degree was gauged from the color changings on the potatoes.FindingsThe distribution of electric field in different needle configuration is found by means of finite element analysis (FEA) and experiments on potatoes. The electric field level of inclined needles was compared with parallel needle case. In particular, the electric field distribution in the case of inclined needles could be very different with respect to the one in the case of parallel needles. The degree of enhancement for different inclinations is visualized by potato color intensity. The FEA suggested that the needle parallelism has to be maintained as possible as if the tips are closer to each other, the electric field intensity could be different with respect to the one in the case of parallel needles.Originality/valueThis paper analyzes the effect of inclined electrodes considering also the non-linearity of tissues.

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Alsaleh, W., and R. Hugtenburg. "161 DEVELOPING COMPUTATIONAL METHODS TO VIEW DISTRIBUTIONS OF SECOND CANCER RISK USING MONTE CARLO AND VOXEL HUMAN PHANTOMS." Radiotherapy and Oncology 102 (March 2012): S75. http://dx.doi.org/10.1016/s0167-8140(12)70132-9.

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Lee, Hyun Cheol, Do Hyeon Yoo, Mauro Testa, Wook-Geun Shin, Hyun Joon Choi, Wi-Ho Ha, Jaeryong Yoo, Seokwon Yoon, and Chul Hee Min. "Effective dose evaluation of NORM-added consumer products using Monte Carlo simulations and the ICRP computational human phantoms." Applied Radiation and Isotopes 110 (April 2016): 230–35. http://dx.doi.org/10.1016/j.apradiso.2016.01.002.

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Lee, Sang-Kyung, Jung Su Kim, Sang-Wook Yoon, and Jung Min Kim. "Development of CT Effective Dose Conversion Factors from Clinical CT Examinations in the Republic of Korea." Diagnostics 10, no. 9 (September 21, 2020): 727. http://dx.doi.org/10.3390/diagnostics10090727.

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The aim of this study was to determine the conversion factors for the effective dose (ED) per dose length product (DLP) for various computed tomography (CT) protocols based on the 2007 recommendations of the International Commission on Radiological Protection (ICRP). CT dose data from 369 CT scanners and 13,625 patients were collected through a nationwide survey. Data from 3793 patients with a difference in height within 5% of computational human phantoms were selected to calculate ED and DLP. The anatomical CT scan ranges for 11 scan protocols (adult-10, pediatric-1) were determined by experts, and scan lengths were obtained by matching scan ranges to computational phantoms. ED and DLP were calculated using the NCICT program. For each CT protocol, ED/DLP conversion factors were calculated from ED and DLP. Estimated ED conversion factors were 0.00172, 0.00751, 0.00858, 0.01843, 0.01103, 0.02532, 0.01794, 0.02811, 0.02815, 0.02175, 0.00626, 0.00458, 0.00308, and 0.00233 mSv∙mGy−1∙cm−1 for the adult brain, intra-cranial angiography, C-spine, L-spine, neck, chest, abdomen and pelvis, coronary angiography, calcium scoring, aortography, and CT examinations of pediatric brain of <2 years, 4–6 years, 9–11 years, and 13–15 years, respectively. We determined ED conversion factors for 11 CT protocols using CT data obtained from a nationwide survey in Korea and Monte Carlo-based dose calculations.

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Maynard, M., J. Geyer, J. Aris, R. Shifrin, and W. Bolch. "SU-E-I-50: The UF Family of Hybrid Phantoms of the Developing Human Fetus for Computational Radiation Dosimetry." Medical Physics 38, no. 6Part4 (June 2011): 3407. http://dx.doi.org/10.1118/1.3611623.

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Menzel, H.-G., and J. D. Harrison. "Doses from radiation exposure." Annals of the ICRP 41, no. 3-4 (October 2012): 12–23. http://dx.doi.org/10.1016/j.icrp.2012.06.023.

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Practical implementation of the International Commission on Radiological Protection's (ICRP) system of protection requires the availability of appropriate methods and data. The work of Committee 2 is concerned with the development of reference data and methods for the assessment of internal and external radiation exposure of workers and members of the public. This involves the development of reference biokinetic and dosimetric models, reference anatomical models of the human body, and reference anatomical and physiological data. Following ICRP's 2007 Recommendations, Committee 2 has focused on the provision of new reference dose coefficients for external and internal exposure. As well as specifying changes to the radiation and tissue weighting factors used in the calculation of protection quantities, the 2007 Recommendations introduced the use of reference anatomical phantoms based on medical imaging data, requiring explicit sex averaging of male and female organ-equivalent doses in the calculation of effective dose. In preparation for the calculation of new dose coefficients, Committee 2 and its task groups have provided updated nuclear decay data (ICRP Publication 107) and adult reference computational phantoms (ICRP Publication 110). New dose coefficients for external exposures of workers are complete (ICRP Publication 116), and work is in progress on a series of reports on internal dose coefficients to workers from inhaled and ingested radionuclides. Reference phantoms for children will also be provided and used in the calculation of dose coefficients for public exposures. Committee 2 also has task groups on exposures to radiation in space and on the use of effective dose.

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Imielinska, Celina, Andrzej Przekwas, and XG Tan. "Multi-Scale Visual Analysis of Trauma Injury." Information Visualization 5, no. 4 (November 30, 2006): 279–89. http://dx.doi.org/10.1057/palgrave.ivs.9500137.

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We develop a multi-scale high-fidelity biomechanical and physiologically based modeling tools for trauma (ballistic/impact and blast) injury to brain, lung and spinal cord for resuscitation, treatment planning and design of personnel protection. Several approaches have been used to study blast and ballistic/impact injuries. Dummy containing pressure sensors and synthetic phantoms of human organs have been used to study bomb blast and car crashes. Large animals like pigs also have been equipped with pressure sensors exposed to blast waves. But these methods do not provide anatomically and physiologically, full optimization of body protection design and require animal sacrifice. Anatomy and medical image-based high-fidelity computational modeling can be used to analyze injury mechanisms and to optimize the design of body protection. This paper presents novel approach of coupled computational fluid dynamics and computational structures dynamics to simulate fluid (air, cerebrospinal fluid)–solid (cranium, brain tissue) interaction during ballistic/blast impact. We propose a trauma injury simulation pipeline concept staring from anatomy and medical image-based high-fidelity 3D geometric modeling, extraction of tissue morphology, generation of computational grids, multi-scale biomechanical and physiological simulations, and data visualization.

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Garzón, W. J., D. F. A. Aldana, and V. F. Cassola. "PATIENT-SPECIFIC ORGAN DOSES FROM PEDIATRIC HEAD CT EXAMINATIONS." Radiation Protection Dosimetry 191, no. 1 (August 2020): 1–8. http://dx.doi.org/10.1093/rpd/ncaa126.

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Abstract The aim of this work was to estimate patient’s organ absorbed doses from pediatric helical head computed tomography (CT) examinations using the Size-Specific Dose Estimate (SSDE) methodology and to determine organ dose to SSDE conversion coefficients for clinical routine. Patient-specific organ and tissue absorbed doses from 139 Head CT scans performed in pediatric patients from 0 to 15 years old in a Public Hospital in Tunja, Colombia were estimated. The calculations were made through Monte Carlo simulations, based on patient-specific information, dosimetric CT quantities (CTDIvol, DLP) and age-specific computational human phantoms matched to patients on the basis of gender and size. SSDE showed to be a good quantity for estimate patient-specific organ doses from pediatric head CT examinations when appropriate phantom’s attenuation-based size metrics are chosen to match for any patient size. Strong correlations between absorbed dose and SSDE were found for skin (R2 = 0.99), brain (R2 = 0.98) and eyes (R2 = 0.97), respectively. Besides, a good correlation between SSDE and absorbed dose to the red bone marrow (tissue extended outside the scan coverage) was observed (R2 = 0.94). SSDE-to-organ-dose conversion coefficients obtained in this study provide a practical way to estimate patient-specific organ head CT doses.

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Pyakuryal, A., B. Moroz, C. Lee, C. Pelletier, J. Jung, and C. Lee. "SU-F-J-174: A Series of Computational Human Phantoms in DICOM-RT Format for Normal Tissue Dose Reconstruction in Epidemiological Studies." Medical Physics 43, no. 6Part11 (June 2016): 3448. http://dx.doi.org/10.1118/1.4956082.

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GEOGHEGAN, PATRICK H., MARK C. JERMY, and DAVID S. NOBES. "A PIV COMPARISON OF THE FLOW FIELD AND WALL SHEAR STRESS IN RIGID AND COMPLIANT MODELS OF HEALTHY CAROTID ARTERIES." Journal of Mechanics in Medicine and Biology 17, no. 03 (July 21, 2016): 1750041. http://dx.doi.org/10.1142/s0219519417500415.

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Certain systems relevant to circulatory disease have walls which are neither rigid nor static, for example, the coronary arteries, the carotid artery and the heart chambers. In vitro modeling allows the fluid mechanics of the circulatory system to be studied without the ethical and safety issues associated with animal and human experiments. Computational methods in which the equations are coupled governing the flow and the elastic walls are maturing. Currently there is a lack of experimental data in compliant arterial systems to validate the numerical predictions. Previous experimental work has commonly used rigid wall boundaries, ignoring the effect of wall compliance. Particle Image Velocimetry is used to provide a direct comparison of both the flow field and wall shear stress (WSS) observed in experimental phantoms of rigid and compliant geometries representing an idealized common carotid artery. The input flow waveform and the mechanical response of the phantom are physiologically realistic. The results show that compliance affects the velocity profile within the artery. A rigid boundary causes severe overestimation of the peak WSS with a maximum relative difference of 61% occurring; showing compliance protects the artery from exposure to high magnitude WSS. This is important when trying to understand the development of diseases like atherosclerosis. The maximum, minimum and time averaged WSS in the rigid geometry was 2.3, 0.51 and 1.03[Formula: see text]Pa and in the compliant geometry 1.4, 0.58 and 0.84[Formula: see text]Pa, respectively.

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Bottauscio, Oriano, Mario Chiampi, and Luca Zilberti. "A boundary element approach to relate surface fields with the specific absorption rate (SAR) induced in 3-D human phantoms." Engineering Analysis with Boundary Elements 35, no. 4 (April 2011): 657–66. http://dx.doi.org/10.1016/j.enganabound.2010.11.012.

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Pelletier, C., J. Jung, C. Lee, A. Pyakuryal, J. Kim, and C. Lee. "SU-E-T-399: Evaluation of Selection Criteria for Computational Human Phantoms for Use in Out-Of-Field Organ Dosimetry for Radiotherapy Patients." Medical Physics 42, no. 6Part18 (June 2015): 3425. http://dx.doi.org/10.1118/1.4924760.

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Van Hooren, Bas, Panayiotis Teratsias, and Emma F. Hodson-Tole. "Ultrasound imaging to assess skeletal muscle architecture during movements: a systematic review of methods, reliability, and challenges." Journal of Applied Physiology 128, no. 4 (April 1, 2020): 978–99. http://dx.doi.org/10.1152/japplphysiol.00835.2019.

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B-mode ultrasound is often used to quantify muscle architecture during movements. Our objectives were to 1) systematically review the reliability of fascicle length (FL) and pennation angles (PA) measured using ultrasound during movements involving voluntary contractions; 2) systematically review the methods used in studies reporting reliability, discuss associated challenges, and provide recommendations to improve the reliability and validity of dynamic ultrasound measurements; and 3) provide an overview of computational approaches for quantifying fascicle architecture, their validity, agreement with manual quantification of fascicle architecture, and advantages and drawbacks. Three databases were searched until June 2019. Studies among healthy human individuals aged 17–85 yr that investigated the reliability of FL or PA in lower-extremity muscles during isoinertial movements and that were written in English were included. Thirty studies ( n = 340 participants) were included for reliability analyses. Between-session reliability as measured by coefficient of multiple correlations (CMC), and coefficient of variation (CV) was FL CMC: 0.89–0.96; CV: 8.3% and PA CMC: 0.87–0.90; CV: 4.5–9.6%. Within-session reliability was FL CMC: 0.82–0.99; CV: 0.0–6.7% and PA CMC: 0.91; CV: 0.0–15.0%. Manual analysis reliability was FL CMC: 0.89–0.96; CV: 0.0–15.9%; PA CMC: 0.84–0.90; and CV: 2.0–9.8%. Computational analysis FL CMC was 0.82–0.99, and PA CV was 14.0–15.0%. Eighteen computational approaches were identified, and these generally showed high agreement with manual analysis and high validity compared with phantoms or synthetic images. B-mode ultrasound is a reliable method to quantify fascicle architecture during movement. Additionally, computational approaches can provide a reliable and valid estimation of fascicle architecture.

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Kuzmin, G., C. Lee, C. Lee, C. Pelletier, and J. Jung. "SU-F-T-114: A Novel Anatomically Predictive Extension Model of Computational Human Phantoms for Dose Reconstruction in Retrospective Epidemiological Studies of Second Cancer Risks in Radiotherapy Patients." Medical Physics 43, no. 6Part14 (June 2016): 3487–88. http://dx.doi.org/10.1118/1.4956250.

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Khankook, Atiyeh Ebrahimi, Hashem Miri Hakimabad, and Laleh Rafat Motavalli. "A feasibility study on the use of phantoms with statistical lung masses for determining the uncertainty in the dose absorbed by the lung from broad beams of incident photons and neutrons." Journal of Radiation Research 58, no. 3 (January 11, 2017): 313–28. http://dx.doi.org/10.1093/jrr/rrw118.

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Abstract Computational models of the human body have gradually become crucial in the evaluation of doses absorbed by organs. However, individuals may differ considerably in terms of organ size and shape. In this study, the authors sought to determine the energy-dependent standard deviations due to lung size of the dose absorbed by the lung during external photon and neutron beam exposures. One hundred lungs with different masses were prepared and located in an adult male International Commission on Radiological Protection (ICRP) reference phantom. Calculations were performed using the Monte Carlo N-particle code version 5 (MCNP5). Variation in the lung mass caused great uncertainty: ~90% for low-energy broad parallel photon beams. However, for high-energy photons, the lung-absorbed dose dependency on the anatomical variation was reduced to <1%. In addition, the results obtained indicated that the discrepancy in the lung-absorbed dose varied from 0.6% to 8% for neutron beam exposure. Consequently, the relationship between absorbed dose and organ volume was found to be significant for low-energy photon sources, whereas for higher energy photon sources the organ-absorbed dose was independent of the organ volume. In the case of neutron beam exposure, the maximum discrepancy (of 8%) occurred in the energy range between 0.1 and 5 MeV.

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Lee, C., C. Lee, S. Lamart, SL Simon, RE Curtis, and P. Inskip. "SU-E-T-285: Use of Computational Human Phantoms Combined with a Treatment Planning System to Study the Sensitivity of Reconstructed Normal Tissue Dose to Patient Size and Assumptions On Second Tumor Location." Medical Physics 40, no. 6Part15 (June 2013): 269–70. http://dx.doi.org/10.1118/1.4814719.

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Henriet, Julien, Christophe Lang, Ronnie Muthada Pottayya, and Karla Breschi. "A SELF-ADAPTABLE DISTRIBUTED CBR VERSION OF THE EQUIVOX SYSTEM." Biomedical Engineering: Applications, Basis and Communications 28, no. 04 (August 2016): 1650028. http://dx.doi.org/10.4015/s1016237216500289.

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Three dimensional (3D) voxel phantoms are numerical representations of human bodies, used by physicians in very different contexts. In the controlled context of hospitals, where from 2 to 10 subjects may arrive per day, phantoms are used to verify computations before therapeutic exposure to radiation of cancerous tumors. In addition, 3D phantoms are used to diagnose the gravity of accidental exposure to radiation. In such cases, there may be from 10 to more than 1000 subjects to be diagnosed simultaneously. In all of these cases, computation accuracy depends on a single such representation. In this paper, we present EquiVox which is a tool composed of several distributed functions and enables to create, as quickly and as accurately as possible, 3D numerical phantoms that fit anyone, whatever the context. It is based on a multi-agent system. Agents are convenient for this kind of structure, they can interact together and they may have individual capacities. In EquiVox, the phantoms adaptation is a key phase based on artificial neural network (ANN) interpolations. Thus, ANNs must be trained regularly in order to take into account newly capitalized subjects and to increase interpolation accuracy. However, ANN training is a time-consuming process. Consequently, we have built Equivox to optimize this process. Thus, in this paper, we present our architecture, based on agents and ANN, and we put the stress on the adaptation module. We propose, next, some experimentations in order to show the efficiency of the EquiVox architecture.

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KIM, Chan Hyeong, Jong Hwi JEONG, and Yeon Soo YEOM. "Recent Advances in Computational Human Phantom for Monte Carlo Dose Calculation." Progress in Nuclear Science and Technology 3 (2012): 7–10. http://dx.doi.org/10.15669/pnst.3.7.

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Mohd Razali, Azhani, and Jaafar Abdullah. "Image Reconstruction of Single Photon Emission Computed Tomography (SPECT) on a Bubble Column Using Expectation Maximization and Exact Inversion Algorithms: Comparison Study by Means of Numerical Phantom." Advanced Materials Research 1087 (February 2015): 424–28. http://dx.doi.org/10.4028/www.scientific.net/amr.1087.424.

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Expectation Maximization Algorithm and the Exact Inversion Formula are two mathematical methods that have been developed for various computational applications, such as in medical imaging, nuclear industries, econometric and sociological studies, as well as chemical engineering industries. These image reconstruction methods are usually used to create the SPECT scan images. However, most of the improvement and development of the images are made by using a medical phantom, such as the human brain phantom. Here, in this paper the reconstruction of images by both algorithms are made by using a numerical phantom of laboratory scale bubble columns due to its wide application in the chemical reaction engineering studies. The results for both algorithms are compared, evaluated and discussed.

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Yeom, Yeon Soo, Jong Hwi Jeong, Min Cheol Han, and Chan Hyeong Kim. "Tetrahedral-mesh-based computational human phantom for fast Monte Carlo dose calculations." Physics in Medicine and Biology 59, no. 12 (May 27, 2014): 3173–85. http://dx.doi.org/10.1088/0031-9155/59/12/3173.

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Islam, Mohammad, Md Ullah, Touhidul Alam, Mandeep Singh, and Mengu Cho. "Microwave Imaging Sensor Using Low Profile Modified Stacked Type Planar Inverted F Antenna." Sensors 18, no. 9 (September 5, 2018): 2949. http://dx.doi.org/10.3390/s18092949.

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Microwave imaging is the technique to identify hidden objects from structures using electromagnetic waves that can be applied in medical diagnosis. The change of dielectric property can be detected using microwave antenna sensor, which can lead to localization of abnormality in the human body. This paper presents a stacked type modified Planar Inverted F Antenna (PIFA) as microwave imaging sensor. Design and performance analysis of the sensor antenna along with computational and experimental analysis to identify concealed object has been investigated in this study. The dimension of the modified PIFA radiating patch is 40 × 20 × 10 mm3. The reflector walls used, are 45 mm in length and 0.2-mm-thick inexpensive copper sheet is considered for the simulation and fabrication which addresses the problems of high expenses in conventional patch antenna. The proposed antenna sensor operates at 1.55–1.68 GHz where the maximum realized gain is 4.5 dB with consistent unidirectional radiation characteristics. The proposed sensor antenna is used to identify tumor in a computational human tissue phantom based on reflection and transmission coefficient. Finally, an experiment has been performed to verify the antenna’s potentiality of detecting abnormality in realistic breast phantom.

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Chanda, Arnab, Tysum Ruchti, and Weston Upchurch. "Biomechanical Modeling of Prosthetic Mesh and Human Tissue Surrogate Interaction." Biomimetics 3, no. 3 (September 18, 2018): 27. http://dx.doi.org/10.3390/biomimetics3030027.

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Surgical repair of hernia and prolapse with prosthetic meshes are well-known to cause pain, infection, hernia recurrence, and mesh contraction and failures. In literature, mesh failure mechanics have been studied with uniaxial, biaxial, and cyclic load testing of dry and wet meshes. Also, extensive experimental studies have been conducted on surrogates, such as non-human primates and rodents, to understand the effect of mesh stiffness, pore size, and knitting patterns on mesh biocompatibility. However, the mechanical properties of such animal tissue surrogates are widely different from human tissues. Therefore, to date, mechanics of the interaction between mesh and human tissues is poorly understood. This work addresses this gap in literature by experimentally and computationally modeling the biomechanical behavior of mesh, sutured to human tissue phantom under tension. A commercially available mesh (Prolene®) was sutured to vaginal tissue phantom material and tested at different uniaxial strains and strain rates. Global and local stresses at the tissue phantom, suture, and mesh were analyzed. The results of this study provide important insights into the mechanics of prosthetic mesh failure and will be indispensable for better mesh design in the future.

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Wu, Yican, Mengyun Cheng, Wen Wang, Jing Song, Shengpeng Yu, Pengcheng Long, and Liqin Hu. "Development of Chinese Female Computational Phantom Rad-Human and Its Application in Radiation Dosimetry Assessment." Nuclear Technology 201, no. 2 (January 19, 2018): 155–64. http://dx.doi.org/10.1080/00295450.2017.1411717.

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Bottan, Simone, Marianne Schmid Daners, Diane de Zelicourt, Norina Fellner, Dimos Poulikakos, and Vartan Kurtcuoglu. "Assessment of intracranial dynamics in hydrocephalus: effects of viscoelasticity on the outcome of infusion tests." Journal of Neurosurgery 119, no. 6 (December 2013): 1511–19. http://dx.doi.org/10.3171/2013.8.jns122497.

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Object The treatment of hydrocephalus requires insight into the intracranial dynamics in the patient. Resistance to CSF outflow (R0) is a clinically obtainable parameter of intracranial fluid dynamics that quantifies the apparent resistance to CSF absorption. It is used as a criterion for the selection of shunt candidates and serves as an indicator of shunt performance. The R0 is obtained clinically by performing 1 of 3 infusion tests: constant flow, constant pressure, or bolus infusion. Among these, the bolus infusion method has the shortest examination times and provides the shortest time of exposure of patients to artificially increased intracranial pressure (ICP) levels. However, for unknown reasons, the bolus infusion method systematically underestimates the R0. Here, the authors have tested and verified the hypothesis that this underestimation is due to lack of accounting for viscoelasticity of the craniospinal space in the calculation of the R0. Methods The authors developed a phantom model of the human craniospinal space in order to reproduce in vivo pressure-volume (PV) relationships during infusion testing. The phantom model followed the Marmarou exponential PV equation and also included a viscoelastic response to volume changes. Parameters of intracranial fluid dynamics, such as the R0, could be controlled and set independently. In addition to the phantom model, the authors designed a computational framework for virtual infusion testing in which viscoelasticity can be turned on or off in a controlled manner. Constant flow, constant pressure, and bolus infusion tests were performed on the phantom model, as well as on the virtual computational platform, using standard clinical protocols. Values for the R0 were derived from each infusion test by using both a standard method based on the Marmarou PV equation and a novel method based on a system identification approach that takes into account viscoelastic behavior. Results Experiments with the phantom model confirmed clinical observations that both the constant flow and constant pressure infusion tests, but not the bolus infusion test, yield correct R0 values when they are determined with the standard method according to Marmarou. Equivalent results were obtained using the computational framework. When the novel system identification approach was used to determine the R0, all of the 3 infusion tests yielded correct values for the R0. Conclusions The authors' investigations demonstrate that intracranial dynamics have a substantial viscoelastic component. When this viscoelastic component is taken into account in calculations, the R0, is no longer underestimated in the bolus infusion test.

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Ullah, Md, Mohammad Islam, Touhidul Alam, and Farhad Ashraf. "Paper-Based Flexible Antenna for Wearable Telemedicine Applications at 2.4 GHz ISM Band." Sensors 18, no. 12 (December 1, 2018): 4214. http://dx.doi.org/10.3390/s18124214.

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This paper demonstrates the performance of a potential design of a paper substrate-based flexible antenna for intrabody telemedicine systems in the 2.4 GHz industrial, scientific, and medical radio (ISM) bands. The antenna was fabricated using 0.54 mm thick flexible photo paper and 0.03 mm copper strips as radiating elements. Design and performance analyses of the antenna were performed using Computer Simulation Technology (CST) Microwave Studio software. The antenna performances were investigated based on the reflection coefficient in normal and bent conditions. The total dimensions of the proposed antenna are 40 × 35 × 0.6 mm3. The antenna operates at 2.33–2.53 GHz in the normal condition. More than an 8% fractional bandwidth is expressed by the antenna. Computational analysis was performed at different flexible curvatures by bending the antenna. The minimum fractional bandwidth deviation is 5.04% and the maximum is 24.97%. Moreover, it was mounted on a homogeneous phantom muscle and a four-layer human tissue phantom. Up to a 70% radiation efficiency with a 2 dB gain was achieved by the antenna. Finally, the performance of the antenna with a homogeneous phantom muscle was measured and found reliable for wearable telemedicine applications.

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Nayak H. S., Sathvik, Nitesh Kumar, S. M. A. Khader, and Raghuvir Pai. "Effect of dome size on flow dynamics in saccular aneurysms – A numerical study." Journal of Mechanical Engineering and Sciences 14, no. 3 (September 30, 2020): 7181–90. http://dx.doi.org/10.15282/jmes.14.3.2020.19.0564.

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Image-based Computational Fluid Dynamic (CFD) simulations of anatomical models of human arteries are gaining clinical relevance in present days. In this study, CFD is used to study flow behaviour and hemodynamic parameters in aneurysms, with a focus on the effect of geometric variations in the aneurysm models on the flow dynamics. A computational phantom was created using a 3D modelling software to mimic a spherical aneurysm. Hemodynamic parameters were obtained and compared with the available literature to validate. Further, flow dynamics is studied by varying the dome size of the aneurysm from 3.75 mm to 6.25 mm with an increment of 0.625 mm keeping the neck size constant. The aneurysm is assumed to be located at a bend in the arterial system. Computational analysis of the flow field is performed by using Navier – Stokes equation for laminar flow of incompressible, Newtonian fluid. Parameters such as velocity, pressure, wall shear stress (WSS), vortex structure are studied. It was observed that the location of the flow separation and WSS vary significantly with the geometry of the aneurysm. The reduction of WSS inside the aneurysm is higher at the larger dome sizes for constant neck size.

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Yoo, Do Hyeon, Wook-Geun Shin, Hyun Cheol Lee, Hyun Joon Choi, Mauro Testa, Jae Kook Lee, Yeon Soo Yeom, Chan Hyeong Kim, and Chul Hee Min. "An effective dose assessment technique with NORM added consumer products using skin-point source on computational human phantom." Applied Radiation and Isotopes 118 (December 2016): 56–61. http://dx.doi.org/10.1016/j.apradiso.2016.08.014.

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Ma, J., A. Wittek, S. Singh, G. Joldes, T. Washio, K. Chinzei, and K. Miller. "Evaluation of accuracy of non-linear finite element computations for surgical simulation: study using brain phantom." Computer Methods in Biomechanics and Biomedical Engineering 13, no. 6 (December 2010): 783–94. http://dx.doi.org/10.1080/10255841003628995.

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Barrance, Peter J., Glenn N. Williams, John E. Novotny, and Thomas S. Buchanan. "A Method for Measurement of Joint Kinematics in Vivo by Registration of 3-D Geometric Models With Cine Phase Contrast Magnetic Resonance Imaging Data." Journal of Biomechanical Engineering 127, no. 5 (May 31, 2005): 829–37. http://dx.doi.org/10.1115/1.1992524.

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A new method is presented for measuring joint kinematics by optimally matching modeled trajectories of geometric surface models of bones with cine phase contrast (cine-PC) magnetic resonance imaging data. The incorporation of the geometric bone models (GBMs) allows computation of kinematics based on coordinate systems placed relative to full 3-D anatomy, as well as quantification of changes in articular contact locations and relative velocities during dynamic motion. These capabilities are additional to those of cine-PC based techniques that have been used previously to measure joint kinematics during activity. Cine-PC magnitude and velocity data are collected on a fixed image plane prescribed through a repetitively moved skeletal joint. The intersection of each GBM with a simulated image plane is calculated as the model moves along a computed trajectory, and cine-PC velocity data are sampled from the regions of the velocity images within the area of this intersection. From the sampled velocity data, the instantaneous linear and angular velocities of a coordinate system fixed to the GBM are estimated, and integration of the linear and angular velocities is used to predict updated trajectories. A moving validation phantom that produces motions and velocity data similar to those observed in an experiment on human knee kinematics was designed. This phantom was used to assess cine-PC rigid body tracking performance by comparing the kinematics of the phantom measured by this method to similar measurements made using a magnetic tracking system. Average differences between the two methods were measured as 2.82 mm rms for anterior∕posterior tibial position, and 2.63 deg rms for axial rotation. An inter-trial repeatability study of human knee kinematics using the new method produced rms differences in anterior∕posterior tibial position and axial rotation of 1.44 mm and 2.35 deg. The performance of the method is concluded to be sufficient for the effective study of kinematic changes caused to knees by soft tissue injuries.

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Lee, Yoo, Yoon, and Song. "A Computationally Efficient Mean Sound Speed Estimation Method Based on an Evaluation of Focusing Quality for Medical Ultrasound Imaging." Electronics 8, no. 11 (November 18, 2019): 1368. http://dx.doi.org/10.3390/electronics8111368.

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Generally, ultrasound receive beamformers calculate the focusing time delays of fixed sound speeds in human tissue (e.g., 1540 m/s). However, phase distortions occur due to variations of sound speeds in soft tissues, resulting in degradation of image quality. Thus, an optimal estimation of sound speed is required in order to improve image quality. Implementation of real-time sound speed estimation is challenging due to high computational and hardware complexities. In this paper, an optimal sound speed estimation method with a low-cost hardware resource is presented. In the proposed method, the optimal mean sound speed is determined by measuring the amplitude variance of pre-beamformed radio-frequency (RF) data. The proposed method was evaluated with phantom and in vivo experiments, and implemented on Virtex-4 with Xilinx ISE 12.4 using VHDL. Experiment results indicate that the proposed method could estimate the mean optimal sound speed and enhance spatial resolution with a negligible increase in the hardware resource usage.

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Ngoepe, Malebogo N., Etheresia Pretorius, Ilunga J. Tshimanga, Zahra Shaikh, Yiannis Ventikos, and Wei Hua Ho. "Thrombin–Fibrinogen In Vitro Flow Model of Thrombus Growth in Cerebral Aneurysms." TH Open 05, no. 02 (April 2021): e155-e162. http://dx.doi.org/10.1055/s-0041-1728790.

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AbstractCerebral aneurysms are balloon-like structures that develop on weakened areas of cerebral artery walls, with a significant risk of rupture. Thrombi formation is closely associated with cerebral aneurysms and has been observed both before and after intervention, leading to a wide variability of outcomes in patients with the condition. The attempt to manage the outcomes has led to the development of various computational models of cerebral aneurysm thrombosis. In the current study, we developed a simplified thrombin–fibrinogen flow system, based on commercially available purified human-derived plasma proteins, which enables thrombus growth and tracking in an idealized cerebral aneurysm geometry. A three-dimensional printed geometry of an idealized cerebral aneurysm and parent vessel configuration was developed. An unexpected outcome was that this phantom-based flow model allowed us to track clot growth over a period of time, by using optical imaging to record the progression of the growing clot into the flow field. Image processing techniques were subsequently used to extract important quantitative metrics from the imaging dataset, such as end point intracranial thrombus volume. The model clearly demonstrates that clot formation, in cerebral aneurysms, is a complex interplay between mechanics and biochemistry. This system is beneficial for verifying computational models of cerebral aneurysm thrombosis, particularly those focusing on initial angiographic occlusion outcomes, and will also assist manufacturers in optimizing interventional device designs.

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Lee, Jun-Seong, Yang-Soo Kim, Min-Gul Kim, Jung-Soo Kim, and Sun-Young Lee. "Evaluation of Absorbed Dose for the Right Lung and Surrounding Organs of the Computational Human Phantom in Brachytherapy by Monte Carlo Simulation." Journal of Radiological Science and Technology 43, no. 6 (December 30, 2020): 443–51. http://dx.doi.org/10.17946/jrst.2020.43.6.443.

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Kaiser, H. J., U. Buell, O. Sabri, and G. Wagenknecht. "MRI-Based Individual 3D Region-of-Interest Atlases of the Human Brain." Methods of Information in Medicine 43, no. 04 (2004): 383–90. http://dx.doi.org/10.1055/s-0038-1633890.

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Summary Objectives: Introduction of a new atlas-based method for analyzing functional data which takes into account the variability of individual human brains and the partial volume effects of functional emission computed tomography images in complex anatomical 3D regions, as well as describing the underlying multi-modal image processing principles. Methods: 3D atlas extraction is done directly by automated segmentation of individual magnetic resonance images of the patient’s head. This is done in two steps: voxel-based classification of T1-weighted images for tissue differentiation (low-level processing) is followed by knowledge-based analysis of the classified images for extraction of 3D anatomical regions (high-level processing). For atlas-based quantification of co-registered functional images, 3D anatomical regions can be convoluted with an idealized point spread function of the emission computed tomography system, after which a partial volume-dependent threshold can be determined. Results: Quantitative evaluation studies, based on 50 realistic software head phantoms and 24 image data sets obtained from healthy subjects and patients, show low misclassification rates and stable results for the neural network-based classification approach (mean ± SD 3.587 ± 0.466%, range 2.726-4.927%) as well as for the adjustable parameters of the knowledge-based approach. Computation time is <5 min for classification, <1 min for most of the extraction algorithms. The influence of the partial volume-dependent threshold is shown for an activation study. Conclusions: This new method allows 3D atlas generation without the need to warp individual image data to an anatomical or statistical brain atlas. Going beyond the purely tissue-oriented approach, partial volume effects of emission computed tomography images can be analyzed in complex anatomical 3D regions.

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Gil Cano, Julio Daniel, Angie Fasoula, Luc Duchesne, and Jean-Gael Bernard. "Wavelia Breast Imaging: The Optical Breast Contour Detection Subsystem." Applied Sciences 10, no. 4 (February 12, 2020): 1234. http://dx.doi.org/10.3390/app10041234.

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Wavelia is a low-power electromagnetic wave breast imaging device for breast cancer diagnosis, which consists of two subsystems, both performing non-invasive examinations: the Microwave Breast Imaging (MBI) subsystem and the Optical Breast Contour Detection (OBCD) subsystem. The Wavelia OBCD subsystem is a 3D scanning device using an infrared 3D stereoscopic camera, which performs an azimuthal scan to acquire 3D point clouds of the external surface of the breast. The OBCD subsystem aims at reconstructing fully the external envelope of the breast, with high precision, to provide the total volume of the breast and morphological data as a priori information to the MBI subsystem. This paper presents a new shape-based calibration procedure for turntable-based 3D scanning devices, a new 3D breast surface reconstruction method based on a linear stretching function, as well as the breast volume computation method that have been developed and integrated with the Wavelia OBCD subsystem, before its installation at the Clinical Research Facility of Galway (CRFG), in Ireland, for first-in-human clinical testing. Indicative results of the Wavelia OBCD subsystem both from scans of experimental breast phantoms and from patient scans are thoroughly presented and discussed in the paper.

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Augst, A. D., D. C. Barratt, A. D. Hughes, F. P. Glor, S. A. McG Thom, and X. Y. Xu. "Accuracy and Reproducibility of CFD Predicted Wall Shear Stress Using 3D Ultrasound Images." Journal of Biomechanical Engineering 125, no. 2 (April 1, 2003): 218–22. http://dx.doi.org/10.1115/1.1553973.

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Computational fluid dynamics (CFD) flow simulation techniques have the potential to enhance our understanding of how haemodynamic factors are involved in atherosclerosis. Recently, 3D ultrasound has emerged as an alternative to other 3D imaging techniques, such as magnetic resonance angiography (MRA). The method can be used to generate realistic vascular geometry suitable for CFD simulations. In order to assess accuracy and reproducibility of the procedure from image acquisition to reconstruction to CFD simulation, a human carotid artery bifurcation phantom was scanned three times using 3D ultrasound. The geometry was reconstructed and flow simulations were carried out on the three sets as well as on a model generated using computer aided design (CAD) from the geometric information given by the manufacturer. It was found that the three reconstructed sets showed good reproducibility as well as satisfactory quantitative agreement with the CAD model. Analyzing two selected locations probably representing the ‘worst cases,’ accuracy comparing ultrasound and CAD reconstructed models was estimated to be between 7.2% and 7.7% of the maximum instantaneous WSS and reproducibility comparing the three scans to be between 8.2% and 10.7% of their average maximum.

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Journal articles on the topic 'Human Computational Phantoms'

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