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Ishii T, Fujimura S, Takao H, Uchiyama Y, Okudaira T, Ishibashi T, Otani K, Karagiozov K, Fukudome K, Yamamoto M, Murayama Y. Hemodynamic and Morphological Factors Related to Coil Compaction in Basilar Artery Tip Aneurysms. World Neurosurg 2021; 155:e95-e110. [PMID: 34389523 DOI: 10.1016/j.wneu.2021.08.011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2021] [Revised: 08/02/2021] [Accepted: 08/03/2021] [Indexed: 11/29/2022]
Abstract
PURPOSE Coil compaction is directly related to the degree of cerebral aneurysmal recanalization. The Degree of Recanalization (DoR) was quantified by measuring the volume vacated by coil deformation. The purpose of this study was to clarify the hemodynamic and morphological factors associated with coil compaction. METHODS Computational fluid dynamics (CFD) simulations were performed on 28 middle size (5-10 mm), unruptured basilar artery tip aneurysms. The DoR was measured by comparing the coil mass shape obtained from three-dimensional digital subtraction angiography data immediately after coil embolization and again within 1 to 2 years of follow-up. Deployed coils were modeled using a virtual coiling technique for CFD simulations. Hemodynamic and morphological factors to predict the DoR were derived using multiple linear regression. RESULTS Aneurysmal neck area, the maximum pressure generated on the neck surface after coil embolization, and the high-pressure position on the neck surface predicted DoR with statistical significance (p<0.001, p<0.001, p=0.004, respectively). DoR tended to increase when the neck area was large, the pressure generated on the coils was high, and the high-pressure position was close to the center of the neck surface. The volume embolization ratio was not statistically relevant for the DoR in the cases of this study. CONCLUSIONS Coil compaction occurs in cerebral aneurysms with a wide neck, high pressure generated on the coils, and high pressure in the center of the neck surface. Establishing the DoR can contribute to the prediction of recanalization after coil embolization.
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Affiliation(s)
- Takumi Ishii
- Graduate School of Mechanical Engineering, Tokyo University of Science, 6-3-1 Niijuku, Katsushika-ku, Tokyo 125-8585, Japan; Department of Innovation for Medical Information Technology, The Jikei University School of Medicine, 3-25-8 Nishi-shinbashi, Minato-ku, Tokyo 105-8461, Japan
| | - Soichiro Fujimura
- Department of Innovation for Medical Information Technology, The Jikei University School of Medicine, 3-25-8 Nishi-shinbashi, Minato-ku, Tokyo 105-8461, Japan; Department of Mechanical Engineering, Tokyo University of Science, 6-3-1 Niijuku, Katsushika-ku, Tokyo 125-8585, Japan
| | - Hiroyuki Takao
- Graduate School of Mechanical Engineering, Tokyo University of Science, 6-3-1 Niijuku, Katsushika-ku, Tokyo 125-8585, Japan; Department of Innovation for Medical Information Technology, The Jikei University School of Medicine, 3-25-8 Nishi-shinbashi, Minato-ku, Tokyo 105-8461, Japan; Department of Neurosurgery, The Jikei University School of Medicine, 3-25-8 Nishi-shinbashi, Minato-ku, Tokyo 105-8461, Japan
| | - Yuya Uchiyama
- Graduate School of Mechanical Engineering, Tokyo University of Science, 6-3-1 Niijuku, Katsushika-ku, Tokyo 125-8585, Japan; Department of Innovation for Medical Information Technology, The Jikei University School of Medicine, 3-25-8 Nishi-shinbashi, Minato-ku, Tokyo 105-8461, Japan
| | - Takuma Okudaira
- Graduate School of Mechanical Engineering, Tokyo University of Science, 6-3-1 Niijuku, Katsushika-ku, Tokyo 125-8585, Japan; Department of Innovation for Medical Information Technology, The Jikei University School of Medicine, 3-25-8 Nishi-shinbashi, Minato-ku, Tokyo 105-8461, Japan
| | - Toshihiro Ishibashi
- Department of Neurosurgery, The Jikei University School of Medicine, 3-25-8 Nishi-shinbashi, Minato-ku, Tokyo 105-8461, Japan
| | - Katharina Otani
- Department of Neurosurgery, The Jikei University School of Medicine, 3-25-8 Nishi-shinbashi, Minato-ku, Tokyo 105-8461, Japan; Siemens Healthcare K.K. 1-11-1 Osaki, Shinagawa-ku, Tokyo 141-8644, Japan
| | - Kostadin Karagiozov
- Department of Neurosurgery, The Jikei University School of Medicine, 3-25-8 Nishi-shinbashi, Minato-ku, Tokyo 105-8461, Japan
| | - Koji Fukudome
- Department of Mechanical Engineering, Tokyo University of Science, 6-3-1 Niijuku, Katsushika-ku, Tokyo 125-8585, Japan
| | - Makoto Yamamoto
- Department of Mechanical Engineering, Tokyo University of Science, 6-3-1 Niijuku, Katsushika-ku, Tokyo 125-8585, Japan
| | - Yuichi Murayama
- Department of Neurosurgery, The Jikei University School of Medicine, 3-25-8 Nishi-shinbashi, Minato-ku, Tokyo 105-8461, Japan.
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Chivukula VK, Marsh L, Chassagne F, Barbour MC, Kelly CM, Levy S, Geindreau C, du Roscoat SR, Kim LJ, Levitt MR, Aliseda A. Lagrangian Trajectory Simulation of Platelets and Synchrotron Microtomography Augment Hemodynamic Analysis of Intracranial Aneurysms Treated With Embolic Coils. J Biomech Eng 2021; 143:071002. [PMID: 33665669 PMCID: PMC8086186 DOI: 10.1115/1.4050375] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2020] [Revised: 02/25/2021] [Indexed: 11/08/2022]
Abstract
As frequency of endovascular treatments for intracranial aneurysms increases, there is a growing need to understand the mechanisms for coil embolization failure. Computational fluid dynamics (CFD) modeling often simplifies modeling the endovascular coils as a homogeneous porous medium (PM), and focuses on the vascular wall endothelium, not considering the biomechanical environment of platelets. These assumptions limit the accuracy of computations for treatment predictions. We present a rigorous analysis using X-ray microtomographic imaging of the coils and a combination of Lagrangian (platelet) and Eulerian (endothelium) metrics. Four patient-specific, anatomically accurate in vitro flow phantoms of aneurysms are treated with the same patient-specific endovascular coils. Synchrotron tomography scans of the coil mass morphology are obtained. Aneurysmal hemodynamics are computationally simulated before and after coiling, using patient-specific velocity/pressure measurements. For each patient, we analyze the trajectories of thousands of platelets during several cardiac cycles, and calculate residence times (RTs) and shear exposure, relevant to thrombus formation. We quantify the inconsistencies of the PM approach, comparing them with coil-resolved (CR) simulations, showing the under- or overestimation of key hemodynamic metrics used to predict treatment outcomes. We fully characterize aneurysmal hemodynamics with converged statistics of platelet RT and shear stress history (SH), to augment the traditional wall shear stress (WSS) on the vascular endothelium. Incorporating microtomographic scans of coil morphology into hemodynamic analysis of coiled intracranial aneurysms, and augmenting traditional analysis with Lagrangian platelet metrics improves CFD predictions, and raises the potential for understanding and clinical translation of computational hemodynamics for intracranial aneurysm treatment outcomes.
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Affiliation(s)
| | - Laurel Marsh
- Department of Mechanical Engineering, University of Washington, Seattle, WA 98195
| | - Fanette Chassagne
- Department of Mechanical Engineering, University of Washington, Seattle, WA 98195
| | - Michael C. Barbour
- Department of Mechanical Engineering, University of Washington, Seattle, WA 98195
| | - Cory M. Kelly
- Department of Neurological Surgery, University of Washington, Seattle, WA 98195; Stroke and Applied Neuroscience Center, University of Washington, Seattle, WA 98195
| | - Samuel Levy
- Department of Neurological Surgery, University of Washington, Seattle, WA 98195; Stroke and Applied Neuroscience Center, University of Washington, Seattle, WA 98195
| | - Christian Geindreau
- Laboratoire 3SR, Université Grenoble Alpes, 1270 Rue de la Piscine, Gières 38610, France
| | | | - Louis J. Kim
- Department of Neurological Surgery, University of Washington, Seattle, WA 98195; Stroke and Applied Neuroscience Center, University of Washington, Seattle, WA 98195; Department of Radiology, University of Washington, Seattle, WA 98195
| | - Michael R. Levitt
- Department of Mechanical Engineering, University of Washington, Seattle, WA 98195; Department of Neurological Surgery, University of Washington, Seattle, WA 98195; Stroke and Applied Neuroscience Center, University of Washington, Seattle, WA 98195; Department of Radiology, University of Washington, Seattle, WA 98195
| | - Alberto Aliseda
- Department of Mechanical Engineering, University of Washington, Seattle, WA 98195; Department of Neurological Surgery, University of Washington, Seattle, WA 98195; Stroke and Applied Neuroscience Center, University of Washington, Seattle, WA 98195
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Fast virtual coiling algorithm for intracranial aneurysms using pre-shape path planning. Comput Biol Med 2021; 134:104496. [PMID: 34077817 DOI: 10.1016/j.compbiomed.2021.104496] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2021] [Revised: 05/11/2021] [Accepted: 05/12/2021] [Indexed: 09/30/2022]
Abstract
To aid in predicting and improving treatment outcome of endovascular coiling of intracranial aneurysms, simulation of patient-specific coil deployment should be both accurate and fast. We developed a fast virtual coiling algorithm called Pre-shape Path Planning (P3). It captures the mechanical propensity of a released coil to restore its pre-shape for bending energy minimization, producing coils without unrealistic kinks and bends. A coil is discretized into finite-length segments and extruded from the delivery catheter segment-by-segment following a generic coil pre-shape. With the release of each segment, coil-wall and coil-coil collisions are detected and resolved. Modeling of each case took seconds to minutes. To test the algorithm, we evaluated its output against the literature, experiments, and patient angiograms. The periphery-to-core ratio of coils deployed by P3 decreased with increasing coil packing density, consistent with observations in the literature. Coils deployed by P3 compared well with in vitro experiments, free from unphysical kinks and loops that arose from previous virtual coiling algorithms. Simulations of coiling in four patient-specific aneurysms agreed well with the patient angiograms. To test the influence of coil pre-shape on P3, we performed hemodynamic simulations in aneurysms with coils deployed by P3 using the generic pre-shape, P3 using a coil-specific pre-shape, and full finite-element-method simulation. We found that the generic pre-shape was sufficient to produce results comparable to virtual coiling by finite element modeling. Based on these findings, P3 can rapidly simulate coiling in patient-specific aneurysms with good accuracy and is thus a potential candidate for clinical treatment planning.
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Takashima K, Ikeda Y, Yoshinaka K, Ohta M, Mori K, Toma N. Evaluation of Contact Force between Aneurysm Model and Coil for Embolization of Intracranial Aneurysms. JOURNAL OF NEUROENDOVASCULAR THERAPY 2020; 15:233-239. [PMID: 37501696 PMCID: PMC10370923 DOI: 10.5797/jnet.oa.2020-0069] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/06/2020] [Accepted: 08/21/2020] [Indexed: 07/29/2023]
Abstract
Objective To ensure safe coil embolization for intracranial aneurysms, it is important to investigate the contact force between the coil and the aneurysm wall. However, it is unclear how the catheter tip position and the diameter of the secondary loop of the coil influence the contact force. In this study, we measured the contact force between a coil and an aneurysm biomodel under different conditions. Methods A commercially available coil was inserted through a microcatheter into a silicone rubber aneurysm model at a constant speed (1 mm/s) using an automatic stage, and the contact force between the coil and the aneurysm wall was measured by a force sensor attached on the aneurysm model. The inner diameter of the spherical aneurysm was 5 mm. The effects of varying the position of the catheter tip (near dome, center, near neck) and the diameter of the secondary coil (4.5 mm) were evaluated. Results When the catheter tip was inserted more deeply into the aneurysm (especially near the dome), the contact force increased. The contact force also increased as the secondary coil diameter was increased with the catheter tip near and in the center of the dome. Conclusion These results suggest that the catheter tip position and the secondary coil diameter affect the contact force. In particular, the contact force should be considered large with the catheter tip near the dome to ensure safe coil deployment.
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Affiliation(s)
- Kazuto Takashima
- Graduate School of Life Science and Systems Engineering, Kyushu Institute of Technology, Kitakyushu, Fukuoka, Japan
| | - Yuta Ikeda
- Graduate School of Life Science and Systems Engineering, Kyushu Institute of Technology, Kitakyushu, Fukuoka, Japan
| | - Kiyoshi Yoshinaka
- Health and Medical Research Institute, National Institute of Advanced Industrial Science and Technology, Tsukuba, Ibaraki, Japan
| | - Makoto Ohta
- Institute of Fluid Science, Tohoku University, Sendai, Miyagi, Japan
| | - Koji Mori
- Graduate School of Sciences and Technology for Innovation, Yamaguchi University, Ube, Yamaguchi, Japan
| | - Naoki Toma
- Graduate School of Medicine, Mie University, Tsu, Mie, Japan
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Rayz VL, Cohen-Gadol AA. Hemodynamics of Cerebral Aneurysms: Connecting Medical Imaging and Biomechanical Analysis. Annu Rev Biomed Eng 2020; 22:231-256. [PMID: 32212833 DOI: 10.1146/annurev-bioeng-092419-061429] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
In the last two decades, numerous studies have conducted patient-specific computations of blood flow dynamics in cerebral aneurysms and reported correlations between various hemodynamic metrics and aneurysmal disease progression or treatment outcomes. Nevertheless, intra-aneurysmal flow analysis has not been adopted in current clinical practice, and hemodynamic factors usually are not considered in clinical decision making. This review presents the state of the art in cerebral aneurysm imaging and image-based modeling, discussing the advantages and limitations of each approach and focusing on the translational value of hemodynamic analysis. Combining imaging and modeling data obtained from different flow modalities can improve the accuracy and fidelity of resulting velocity fields and flow-derived factors that are thought to affect aneurysmal disease progression. It is expected that predictive models utilizing hemodynamic factors in combination with patient medical history and morphological data will outperform current risk scores and treatment guidelines. Possible future directions include novel approaches enabling data assimilation and multimodality analysis of cerebral aneurysm hemodynamics.
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Affiliation(s)
- Vitaliy L Rayz
- Weldon School of Biomedical Engineering and School of Mechanical Engineering, Purdue University, West Lafayette, Indiana 47907, USA;
| | - Aaron A Cohen-Gadol
- Department of Neurosurgery, Indiana University School of Medicine, Indianapolis, Indiana 46202, USA.,Goodman Campbell Brain and Spine, Carmel, Indiana 46032, USA
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Damiano RJ, Tutino VM, Lamooki SR, Paliwal N, Dargush GF, Davies JM, Siddiqui AH, Meng H. Improving accuracy for finite element modeling of endovascular coiling of intracranial aneurysm. PLoS One 2019; 14:e0226421. [PMID: 31881029 PMCID: PMC6934293 DOI: 10.1371/journal.pone.0226421] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2019] [Accepted: 11/10/2019] [Indexed: 11/18/2022] Open
Abstract
BACKGROUND Computer modeling of endovascular coiling intervention for intracranial aneurysm could enable a priori patient-specific treatment evaluation. To that end, we previously developed a finite element method (FEM) coiling technique, which incorporated simplified assumptions. To improve accuracy in capturing real-life coiling, we aimed to enhance the modeling strategies and experimentally test whether improvements lead to more accurate coiling simulations. METHODS We previously modeled coils using a pre-shape based on mathematical curves and mechanical properties based on those of platinum wires. In the improved version, to better represent the physical properties of coils, we model coil pre-shapes based on how they are manufactured, and their mechanical properties based on their spring-like geometric structures. To enhance the deployment mechanics, we include coil advancement to the aneurysm in FEM simulations. To test if these new strategies produce more accurate coil deployments, we fabricated silicone phantoms of 2 patient-specific aneurysms in duplicate, deployed coils in each, and quantified coil distributions from intra-aneurysmal cross-sections using coil density (CD) and lacunarity (L). These deployments were simulated 9 times each using the original and improved techniques, and CD and L were calculated for cross-sections matching those in the experiments. To compare the 2 simulation techniques, Euclidean distances (dMin, dMax, and dAvg) between experimental and simulation points in standardized CD-L space were evaluated. Univariate tests were performed to determine if these distances were significantly different between the 2 simulations. RESULTS Coil deployments using the improved technique agreed better with experiments than the original technique. All dMin, dMax, and dAvg values were smaller for the improved technique, and the average values across all simulations for the improved technique were significantly smaller than those from the original technique (dMin: p = 0.014, dMax: p = 0.013, dAvg: p = 0.045). CONCLUSION Incorporating coil-specific physical properties and mechanics improves accuracy of FEM simulations of endovascular intracranial aneurysm coiling.
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Affiliation(s)
- Robert J. Damiano
- Department of Mechanical and Aerospace Engineering, University at Buffalo, State University of New York, Buffalo, New York, United States of America
- Canon Stroke & Vascular Research Center, University at Buffalo, State University of New York, Buffalo, New York, United States of America
| | - Vincent M. Tutino
- Canon Stroke & Vascular Research Center, University at Buffalo, State University of New York, Buffalo, New York, United States of America
- Department of Neurosurgery, University at Buffalo, State University of New York, Buffalo, New York, United States of America
- Department of Pathology and Anatomical Sciences, University at Buffalo, State University of New York, Buffalo, New York, United States of America
- Department of Biomedical Engineering, University at Buffalo, State University of New York, Buffalo, New York, United States of America
| | - Saeb R. Lamooki
- Department of Mechanical and Aerospace Engineering, University at Buffalo, State University of New York, Buffalo, New York, United States of America
- Canon Stroke & Vascular Research Center, University at Buffalo, State University of New York, Buffalo, New York, United States of America
| | - Nikhil Paliwal
- Department of Mechanical and Aerospace Engineering, University at Buffalo, State University of New York, Buffalo, New York, United States of America
- Canon Stroke & Vascular Research Center, University at Buffalo, State University of New York, Buffalo, New York, United States of America
| | - Gary F. Dargush
- Department of Mechanical and Aerospace Engineering, University at Buffalo, State University of New York, Buffalo, New York, United States of America
| | - Jason M. Davies
- Department of Neurosurgery, University at Buffalo, State University of New York, Buffalo, New York, United States of America
| | - Adnan H. Siddiqui
- Canon Stroke & Vascular Research Center, University at Buffalo, State University of New York, Buffalo, New York, United States of America
- Department of Neurosurgery, University at Buffalo, State University of New York, Buffalo, New York, United States of America
| | - Hui Meng
- Department of Mechanical and Aerospace Engineering, University at Buffalo, State University of New York, Buffalo, New York, United States of America
- Canon Stroke & Vascular Research Center, University at Buffalo, State University of New York, Buffalo, New York, United States of America
- Department of Neurosurgery, University at Buffalo, State University of New York, Buffalo, New York, United States of America
- Department of Biomedical Engineering, University at Buffalo, State University of New York, Buffalo, New York, United States of America
- * E-mail:
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7
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Investigation of a Promoted You Only Look Once Algorithm and Its Application in Traffic Flow Monitoring. APPLIED SCIENCES-BASEL 2019. [DOI: 10.3390/app9173619] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
We propose a high-performance algorithm while using a promoted and modified form of the You Only Look Once (YOLO) model, which is based on the TensorFlow framework, to enhance the real-time monitoring of traffic-flow problems by an intelligent transportation system. Real-time detection and traffic-flow statistics were realized by adjusting the network structure, optimizing the loss function, and introducing weight regularization. This model, which we call YOLO-UA, was initialized based on the weight of a YOLO model pre-trained while using the VOC2007 data set. The UA-CAR data set with complex weather conditions was used for training, and better model parameters were selected through tests and subsequent adjustments. The experimental results showed that, for different weather scenarios, the accuracy of the YOLO-UA was ~22% greater than that of the YOLO model before optimization, and the recall rate increased by about 21%. On both cloudy and sunny days, the accuracy, precision, and recall rate of the YOLO-UA model were more than 94% above the floating rate, which suggested that the precision and recall rate achieved a good balance. When used for video testing, the YOLO-UA model yielded traffic statistics with an accuracy of up to 100%; the time to count the vehicles in each frame was less than 30 ms and it was highly robust in response to changes in scenario and weather.
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Reconstructing patient-specific cerebral aneurysm vasculature for in vitro investigations and treatment efficacy assessments. J Clin Neurosci 2018; 61:153-159. [PMID: 30470652 DOI: 10.1016/j.jocn.2018.10.103] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2018] [Accepted: 10/27/2018] [Indexed: 11/27/2022]
Abstract
Perianeurysmal hemodynamics play a vital role in the initiation, growth and rupture of intracranial aneurysms. In vitro investigations of aneurysmal hemodynamics are helpful to visualize and measure blood flow, and aiding surgical planning approaches. Improving in vitro model creation can improve the feasibility and accuracy of hemodynamic investigations and surgical planning, improving clinical value. In this study, in vitro models were created from three-dimensional rotational angiography (3DRA) of six patients harboring intracranial aneurysms using a multi-step process involving 3D printing, index of refraction matching and silicone casting that renders the models transparent for flow visualization. Each model was treated with the same commercially-available, patient-specific, endovascular devices (coils and/or stents). All models were scanned by synchrotron X-ray microtomography to obtain high-resolution imaging of the vessel lumen, aneurysmal sac and endovascular devices. Dimensional accuracy was compared by quantifying the differences between the microtomographic reconstructions of the fabricated phantoms and the original 3DRA obtained during patient treatment. True-scale in vitro flow phantoms were successfully created for all six patients. Optical transparency was verified by using an index of refraction matched working fluid that replicated the mechanical behavior of blood. Synchrotron imaging of vessel lumen, aneurysmal sac and endovascular devices was successfully obtained, and dimensional errors were found to be O(100 μm). The creation of dimensionally-accurate, optically-transparent flow phantoms of patient-specific intracranial aneurysms is feasible using 3D printing technology. Such models may enable in vitro investigations of aneurysmal hemodynamics to aid in treatment planning and outcome prediction to devise optimal patient-specific neurointerventional strategies.
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Chen Z, Chen D, Wang X, Damiano RJ, Meng H, Xu J. Novel Geometric Approach for Virtual Coiling. THEORETICAL COMPUTER SCIENCE 2018; 734:3-14. [PMID: 30250355 PMCID: PMC6150465 DOI: 10.1016/j.tcs.2018.02.013] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Endovascular coiling is a primary treatment for intra-cranial aneurysm, which deploys a thin and detachable metal wire inside the aneurysm so as to prevent its rupture. Emerging evidence from medical research and clinical practice has suggested that the coil configuration inside the aneurysm plays a vital role in properly treating aneurysm and predicting its outcome. In this paper, we propose a novel virtual coiling technique, called Ball Winding, for generating a coil configuration with ensured blocking ability. It can be used as an automatic tool for virtually simulating coiling before its implantation and thus optimizes such treatments. Our approach is based on integer linear programming and computational geometry techniques, and takes into consideration the packing density and coil distribution as the performance measurements. The resulting coiling is deployable (with the help of coil pre-shaping) and with minimized energy. Experimental results on both random and real aneurysm data suggest that our proposed method yields near optimal solution.
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Affiliation(s)
- Zihe Chen
- State University of New York at Buffalo
| | | | | | | | - Hui Meng
- State University of New York at Buffalo
| | - Jinhui Xu
- State University of New York at Buffalo
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10
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Leng X, Wang Y, Xu J, Jiang Y, Zhang X, Xiang J. Numerical simulation of patient-specific endovascular stenting and coiling for intracranial aneurysm surgical planning. J Transl Med 2018; 16:208. [PMID: 30031395 PMCID: PMC6054731 DOI: 10.1186/s12967-018-1573-9] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2018] [Accepted: 07/07/2018] [Indexed: 11/17/2022] Open
Abstract
Background In this study, we develop reliable and practical virtual coiling and stenting methods for intracranial aneurysm surgical planning. Since the purpose of deploying coils and stents is to provide device geometries for subsequent accurate post-treatment computational fluid dynamics analysis, we do not need to accurately capture all the details such as the stress and force distribution for the devices and vessel walls. Our philosophy for developing these methods is to balance accuracy and practicality. Methods We consider the mechanical properties of the devices and recapitulate the clinical practice using a finite element method (FEM) approach. At the same time, we apply some simplifications for FEM modeling to make our methods efficient. For the virtual coiling, the coils are modeled as 3D Euler–Bernoulli beam elements, which is computationally efficient and provides good geometry representation. During the stent deployment process, the stent–catheter system is transformed according to the centerline of the parent vessel since the final configuration of the stent is not dependent of the deployment history. The aneurysm and vessel walls are assumed to be rigid and are fully constrained during the simulation. All stent–catheter system and coil–catheter system are prepared and packaged as a library which contains all types of stents, coils and catheters, which improves the efficiency of surgical planning process. Results The stent was delivered to the suitable position during the clinical treatment, achieving good expansion and apposition of the stent to the arterial wall. The coil was deployed into the aneurysm sac and deformed to different shapes because of the stored strain energy during coil package process and the direction of the microcatheter. Conclusions The method which we develop here could become surgical planning for intracranial aneurysm treatment in the clinical workflow.
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Affiliation(s)
- Xiaochang Leng
- ArteryFlow Technology Co., Ltd, 459 Qianmo Road, Suite C1-501, Binjiang District, Hangzhou, 310000, Zhejiang Province, China
| | - Yang Wang
- Department of Neurosurgery, The First Affiliated Hospital of Nanchang University, Nanchang University, Nanchang, China
| | - Jing Xu
- Department of Neurosurgery, The Second Affiliated Hospital of Zhejiang University, Zhejiang University, Hangzhou, China
| | - Yeqing Jiang
- Department of Radiology, Huashan Hospital Affiliated to Fudan University, No. 12 Wulumuqi Zhong Road, Shanghai, 200040, China
| | - Xiaolong Zhang
- Department of Radiology, Huashan Hospital Affiliated to Fudan University, No. 12 Wulumuqi Zhong Road, Shanghai, 200040, China.
| | - Jianping Xiang
- ArteryFlow Technology Co., Ltd, 459 Qianmo Road, Suite C1-501, Binjiang District, Hangzhou, 310000, Zhejiang Province, China.
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Otani T, Shindo T, Ii S, Hirata M, Wada S. Effect of Local Coil Density on Blood Flow Stagnation in Densely Coiled Cerebral Aneurysms: A Computational Study Using a Cartesian Grid Method. J Biomech Eng 2018; 140:2671737. [DOI: 10.1115/1.4039150] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2017] [Indexed: 11/08/2022]
Abstract
Aneurysm recurrence is the most critical concern following coil embolization of a cerebral aneurysm. Adequate packing density (PD) and coil uniformity are believed necessary to achieve sufficient flow stagnation, which decreases the risk of aneurysm recurrence. The effect of coil distribution on the extent of flow stagnation, however, especially in cases of dense packing (high PD), has received less attention. Thus, the cause of aneurysm recurrence despite dense packing is still an open question. The primary aim of this study is to evaluate the effect of local coil density on the extent of blood flow stagnation in densely coiled aneurysms. For this purpose, we developed a robust computational framework to determine blood flow using a Cartesian grid method, by which the complex fluid pathways in coiled aneurysms could be flexibly treated using an implicit function. This tool allowed us to conduct blood flow analyses in two patient-specific geometries with 50 coil distribution patterns in each aneurysm at clinically adequate PD. The results demonstrated that dense packing in the aneurysm may not necessarily block completely the inflow into the aneurysm and local flow that formed in the neck region, whose strength was inversely related to this local PD. This finding suggests that local coil density in the neck region still plays an important role in disturbing the remaining local flow, which possibly prevents thrombus formation in a whole aneurysm sac, increasing the risk of aneurysm regrowth and subsequent recurrence.
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Affiliation(s)
- Tomohiro Otani
- Mem. ASME Department of Mechanical Science and Bioengineering, Graduate School of Engineering Science, Osaka University, 1-3 Machikaneyamacho, Toyonaka-shi 560-8531, Osaka, Japan e-mail:
| | - Takuya Shindo
- Department of Systems Science, School of Engineering Science, Osaka University, 1-3 Machikaneyamacho, Toyonaka-shi 560-8531, Osaka, Japan e-mail:
| | - Satoshi Ii
- Department of Mechanical Science and Bioengineering, Graduate School of Engineering Science, Osaka University, 1-3 Machikaneyamacho, Toyonaka-shi 560-8531, Osaka, Japan e-mail:
| | - Masayuki Hirata
- Department of Neurosurgery, Graduate School of Medicine and Global Center for Medical Engineering and Informatics (MEI Center), Osaka University, 2-2 Yamadaoka, Suita-shi 560-0871, Osaka, Japan e-mail:
| | - Shigeo Wada
- Department of Mechanical Science and Bioengineering, Graduate School of Engineering Science, Osaka University, 1-3 Machikaneyamacho, Toyonaka-shi 560-8531, Osaka, Japan e-mail:
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Sadasivan C, Swartwout E, Kappel AD, Woo HH, Fiorella DJ, Lieber BB. In vitro measurement of the permeability of endovascular coils deployed in cerebral aneurysms. J Neurointerv Surg 2018; 10:896-900. [PMID: 29298858 DOI: 10.1136/neurintsurg-2017-013481] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2017] [Revised: 12/04/2017] [Accepted: 12/07/2017] [Indexed: 11/03/2022]
Abstract
BACKGROUND AND PURPOSE Aneurysm recurrence is the primary limitation of endovascular coiling treatment for cerebral aneurysms. Coiling is currently quantified by a volumetric porosity measure called packing density (pd). Blood flow through a coil mass depends on the permeability of the coil mass, and not just its pd. The permeability of coil masses has not yet been quantified. Here we measure coil permeability with a traditional falling-head permeameter modified to incorporate idealized aneurysms. METHODS Silicone replicas of idealized aneurysms were manufactured with three different aneurysm diameters (4, 5, and 8 mm). Four different coil types (Codman Trufill Orbit, Covidien Axium, Microvention Microplex 10, and Penumbra 400) were deployed into the aneurysms with a target pd of 35%. Coiled replicas were installed on a falling-head permeameter setup and the time taken for a column of fluid above the aneurysm to drop a certain height was recorded. Permeability of the samples was calculated based on a simple modification of the traditional permeameter equation to incorporate a spherical aneurysm. RESULTS The targeted 35% pd was achieved for all samples (35%±1%, P=0.91). Coil permeabilities were significantly different from each other (P<0.001) at constant pd. Microplex 10 coils had the lowest permeability of all coil types. Data suggest a trend of increasing permeability with thicker coil wire diameter (not statistically significant). CONCLUSIONS A simple in vitro setup was developed to measure the permeabilities of coil masses based on traditional permeametry. Coil permeability should be considered when evaluating the hemodynamic efficacy of coiling instead of just packing density. Coils made of thicker wires may be more permeable, and thus less effective, than coils made from thinner wires. Whether aneurysm recurrence is affected by coil wire diameter or permeability needs to be confirmed with clinical trials.
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Affiliation(s)
- Chander Sadasivan
- Department of Neurological Surgery, Stony Brook University, Stony Brook, New York, USA
| | - Erica Swartwout
- Department of Neurological Surgery, Stony Brook University, Stony Brook, New York, USA
| | - Ari D Kappel
- Department of Neurological Surgery, Stony Brook University, Stony Brook, New York, USA
| | - Henry H Woo
- Department of Neurological Surgery, Stony Brook University, Stony Brook, New York, USA
| | - David J Fiorella
- Department of Neurological Surgery, Stony Brook University, Stony Brook, New York, USA
| | - Barry B Lieber
- Department of Neurological Surgery, Stony Brook University, Stony Brook, New York, USA
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Fujimura S, Takao H, Suzuki T, Dahmani C, Ishibashi T, Mamori H, Yamamoto M, Murayama Y. Hemodynamics and coil distribution with changing coil stiffness and length in intracranial aneurysms. J Neurointerv Surg 2017; 10:797-801. [PMID: 29259122 PMCID: PMC6204941 DOI: 10.1136/neurintsurg-2017-013457] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2017] [Revised: 11/25/2017] [Accepted: 11/27/2017] [Indexed: 12/02/2022]
Abstract
Purpose The purpose of this study was to investigate hemodynamics and coil distribution with changing coil stiffness and length using the finite element method (FEM) and computational fluid dynamics (CFD) analysis. Methods Basic side-wall and bifurcation type aneurysm models were used. Six types of coil models were generated by changing the coil stiffness and length, based on commercially available embolic coils. Coil embolization was simulated using FEM. CFD was performed to characterize the hemodynamics in the aneurysms after embolization. Coil distribution and velocity reduction in the aneurysms were evaluated. Results The median value of radial coil distribution was shifted from the center to the outer side of the aneurysmal dome by changing coil stiffness: harder coils entered the outer side of the aneurysmal dome more easily. Short coils were more distributed at the neck region, since their small size made it easy for them to enter the tighter area. CFD results also indicated that velocity in the aneurysm was effectively reduced when the coils were more distributed at the neck region and the outer side of the aneurysmal dome because of the disturbance in blood inflow. Conclusions It is easier for coils to enter the outer side of the aneurysmal sphere when they are harder. If coils are short, they can enter tighter areas more easily. In addition, high coil density at the outer side of the aneurysmal dome and at the neck region is important to achieve effective velocity reduction.
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Affiliation(s)
- Soichiro Fujimura
- Graduate School of Mechanical Engineering, Tokyo University of Science, Tokyo, Japan.,Department of Innovation for Medical Information Technology, The Jikei University School of Medicine, Tokyo, Japan
| | - Hiroyuki Takao
- Department of Innovation for Medical Information Technology, The Jikei University School of Medicine, Tokyo, Japan.,Department of Neurosurgery, The Jikei University School of Medicine, Tokyo, Japan
| | - Takashi Suzuki
- Department of Innovation for Medical Information Technology, The Jikei University School of Medicine, Tokyo, Japan.,Department of Mechanical Engineering, Tokyo University of Science, Tokyo, Japan
| | - Chihebeddine Dahmani
- Department of Neurosurgery, The Jikei University School of Medicine, Tokyo, Japan.,Siemens Healthcare KK, Tokyo, Japan
| | - Toshihiro Ishibashi
- Department of Neurosurgery, The Jikei University School of Medicine, Tokyo, Japan
| | - Hiroya Mamori
- Department of Mechanical Engineering, Tokyo University of Science, Tokyo, Japan
| | - Makoto Yamamoto
- Department of Mechanical Engineering, Tokyo University of Science, Tokyo, Japan
| | - Yuichi Murayama
- Department of Neurosurgery, The Jikei University School of Medicine, Tokyo, Japan
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Miraucourt O, Salmon S, Szopos M, Thiriet M. Blood flow in the cerebral venous system: modeling and simulation. Comput Methods Biomech Biomed Engin 2016; 20:471-482. [PMID: 27802781 DOI: 10.1080/10255842.2016.1247833] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
The development of a software platform incorporating all aspects, from medical imaging data, through three-dimensional reconstruction and suitable meshing, up to simulation of blood flow in patient-specific geometries, is a crucial challenge in biomedical engineering. In the present study, a fully three-dimensional blood flow simulation is carried out through a complete rigid macrovascular circuit, namely the intracranial venous network, instead of a reduced order simulation and partial vascular network. The biomechanical modeling step is carefully analyzed and leads to the description of the flow governed by the dimensionless Navier-Stokes equations for an incompressible viscous fluid. The equations are then numerically solved with a free finite element software using five meshes of a realistic geometry obtained from medical images to prove the feasibility of the pipeline. Some features of the intracranial venous circuit in the supine position such as asymmetric behavior in merging regions are discussed.
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Affiliation(s)
- Olivia Miraucourt
- a Laboratoire de Mathématiques, EA 4535 FR CNRS ARC 3399 , Université de Reims Champagne-Ardenne, UFR Sciences Exactes et Naturelles , Reims Cedex 2 , France
| | - Stéphanie Salmon
- a Laboratoire de Mathématiques, EA 4535 FR CNRS ARC 3399 , Université de Reims Champagne-Ardenne, UFR Sciences Exactes et Naturelles , Reims Cedex 2 , France
| | - Marcela Szopos
- b Université de Strasbourg , CNRS, IRMA UMR 7501 , F-67000 Strasbourg , France
| | - Marc Thiriet
- c Laboratoire J.-L. Lions , UMR 7598 CNRS/Université Pierre et Marie Curie-Paris 6 , Paris , France .,d INRIA, Equipe-projet REO , Le Chesnay , France
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15
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Otani T, Ii S, Shigematsu T, Fujinaka T, Hirata M, Ozaki T, Wada S. Computational study for the effects of coil configuration on blood flow characteristics in coil-embolized cerebral aneurysm. Med Biol Eng Comput 2016; 55:697-710. [DOI: 10.1007/s11517-016-1541-6] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2015] [Accepted: 06/29/2016] [Indexed: 11/28/2022]
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16
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Wall shear stress at the initiation site of cerebral aneurysms. Biomech Model Mechanobiol 2016; 16:97-115. [DOI: 10.1007/s10237-016-0804-3] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2015] [Accepted: 06/24/2016] [Indexed: 11/30/2022]
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Frangi AF, Taylor ZA, Gooya A. Precision Imaging: more descriptive, predictive and integrative imaging. Med Image Anal 2016; 33:27-32. [PMID: 27373145 DOI: 10.1016/j.media.2016.06.024] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2016] [Revised: 06/15/2016] [Accepted: 06/15/2016] [Indexed: 12/22/2022]
Abstract
Medical image analysis has grown into a matured field challenged by progress made across all medical imaging technologies and more recent breakthroughs in biological imaging. The cross-fertilisation between medical image analysis, biomedical imaging physics and technology, and domain knowledge from medicine and biology has spurred a truly interdisciplinary effort that stretched outside the original boundaries of the disciplines that gave birth to this field and created stimulating and enriching synergies. Consideration on how the field has evolved and the experience of the work carried out over the last 15 years in our centre, has led us to envision a future emphasis of medical imaging in Precision Imaging. Precision Imaging is not a new discipline but rather a distinct emphasis in medical imaging borne at the cross-roads between, and unifying the efforts behind mechanistic and phenomenological model-based imaging. It captures three main directions in the effort to deal with the information deluge in imaging sciences, and thus achieve wisdom from data, information, and knowledge. Precision Imaging is finally characterised by being descriptive, predictive and integrative about the imaged object. This paper provides a brief and personal perspective on how the field has evolved, summarises and formalises our vision of Precision Imaging for Precision Medicine, and highlights some connections with past research and current trends in the field.
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Affiliation(s)
- Alejandro F Frangi
- CISTIB Centre for Computational Imaging & Simulation Technologies in Biomedicine, Electronic and Electrical Engineering Department, University of Sheffield, Sheffield, UK.
| | - Zeike A Taylor
- CISTIB Centre for Computational Imaging & Simulation Technologies in Biomedicine, Mechanical Engineering Department, University of Sheffield, Sheffield, UK.
| | - Ali Gooya
- CISTIB Centre for Computational Imaging & Simulation Technologies in Biomedicine, Electronic and Electrical Engineering Department, University of Sheffield, Sheffield, UK.
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A Computational Framework for Personalized Blood Flow Analysis in the Human Left Atrium. Ann Biomed Eng 2016; 44:3284-3294. [DOI: 10.1007/s10439-016-1590-x] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2015] [Accepted: 03/07/2016] [Indexed: 01/30/2023]
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20
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Chung B, Cebral JR. CFD for Evaluation and Treatment Planning of Aneurysms: Review of Proposed Clinical Uses and Their Challenges. Ann Biomed Eng 2014; 43:122-38. [DOI: 10.1007/s10439-014-1093-6] [Citation(s) in RCA: 81] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2014] [Accepted: 08/08/2014] [Indexed: 11/29/2022]
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Accuracy and Reproducibility of Patient-Specific Hemodynamic Models of Stented Intracranial Aneurysms: Report on the Virtual Intracranial Stenting Challenge 2011. Ann Biomed Eng 2014; 43:154-67. [DOI: 10.1007/s10439-014-1082-9] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2014] [Accepted: 07/31/2014] [Indexed: 10/24/2022]
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22
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Approximating hemodynamics of cerebral aneurysms with steady flow simulations. J Biomech 2014; 47:178-85. [DOI: 10.1016/j.jbiomech.2013.09.033] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2013] [Revised: 09/10/2013] [Accepted: 09/17/2013] [Indexed: 11/19/2022]
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Morales HG, Larrabide I, Geers AJ, Aguilar ML, Frangi AF. Newtonian and non-Newtonian blood flow in coiled cerebral aneurysms. J Biomech 2013; 46:2158-64. [DOI: 10.1016/j.jbiomech.2013.06.034] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2013] [Revised: 06/18/2013] [Accepted: 06/30/2013] [Indexed: 10/26/2022]
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Castro MA. Understanding the role of hemodynamics in the initiation, progression, rupture, and treatment outcome of cerebral aneurysm from medical image-based computational studies. ISRN RADIOLOGY 2013; 2013:602707. [PMID: 24967285 PMCID: PMC4045510 DOI: 10.5402/2013/602707] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 05/15/2013] [Accepted: 06/19/2013] [Indexed: 12/31/2022]
Abstract
About a decade ago, the first image-based computational hemodynamic studies of cerebral aneurysms were presented. Their potential for clinical applications was the result of a right combination of medical image processing, vascular reconstruction, and grid generation techniques used to reconstruct personalized domains for computational fluid and solid dynamics solvers and data analysis and visualization techniques. A considerable number of studies have captivated the attention of clinicians, neurosurgeons, and neuroradiologists, who realized the ability of those tools to help in understanding the role played by hemodynamics in the natural history and management of intracranial aneurysms. This paper intends to summarize the most relevant results in the field reported during the last years.
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Affiliation(s)
- Marcelo A. Castro
- Grupo de Investigación y Desarrollo en Bioingeniería, Facultad Regional Buenos Aires, Universidad Tecnológica Nacional, CONICET, Medrano 951, CP 1179, Buenos Aires, Argentina
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Otani T, Nakamura M, Fujinaka T, Hirata M, Kuroda J, Shibano K, Wada S. Computational fluid dynamics of blood flow in coil-embolized aneurysms: effect of packing density on flow stagnation in an idealized geometry. Med Biol Eng Comput 2013; 51:901-10. [PMID: 23529587 DOI: 10.1007/s11517-013-1062-5] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2012] [Accepted: 03/10/2013] [Indexed: 11/30/2022]
Abstract
Coil embolization is performed to induce flow stagnation in cerebral aneurysms and enhance blood clot formation, thus preventing rupture and further growth. We investigated hemodynamics in differently positioned aneurysms coiled at various packing densities to determine the effective packing density in terms of flow stagnation. As a first step, hemodynamic simulations were conducted for idealized geometries of both terminal- and sidewall-type aneurysms. Porous media modeling was employed to describe blood flow in coil-embolized aneurysms. The stagnant volume ratio (SVR) was analyzed to quantify the efficacy of coil embolization. Regardless of aneurysm type and angle, SVR increased with increasing packing density, but the increase in SVR varied depending on type. For sidewall-type aneurysms, the packing density required to achieve 60 % SVR was 20 %, roughly independent of aneurysm angle; flow stagnation was achieved at low packing density. In contrast, in terminal-type aneurysms, the packing density required to achieve 60 % SVR was highly dependent on aneurysm angle, accomplishing a 20 % packing density only for lower angles. Indications are that a relatively high packing density would be required, particularly when these aneurysms are angled against the parent artery. The packing density required for flow stagnation varies depending on aneurysm type and relative position.
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Affiliation(s)
- Tomohiro Otani
- Graduate School of Engineering Science, Osaka University, Machikaneyama-chou 1-3, Toyonaka, Osaka 560-8531, Japan
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Frangi AF, Hose DR, Hunter PJ, Ayache N, Brooks D. Special issue on medical imaging and image computing in computational physiology. IEEE TRANSACTIONS ON MEDICAL IMAGING 2013; 32:1-7. [PMID: 23409282 DOI: 10.1109/tmi.2012.2234320] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
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