Article
Clinical Neurology
Jinyu Xu, Christof Karmonik, Ying Yu, Nan Lv, Zhaoyue Shi, Jian-Min Liu, Qinghai Huang
Summary: The study evaluated an alternative strategy of modeling FD effects for the Tubridge system using a porous medium to reduce demands on time and complexity of simulation procedures. Comparisons between the porous medium approach and direct virtual FD simulations showed comparable hemodynamic alterations, with a significant reduction in modeling complexity and computation time.
WORLD NEUROSURGERY
(2022)
Article
Biotechnology & Applied Microbiology
Yuya Uchiyama, Soichiro Fujimura, Hiroyuki Takao, Takashi Suzuki, Motoharu Hayakawa, Toshihiro Ishibashi, Kostadin Karagiozov, Koji Fukudome, Yuichi Murayama, Makoto Yamamoto
Summary: This study investigated the hemodynamics of overlapping flow diverters (FDs) using computational fluid dynamics (CFD) simulations. Results showed significant changes in blood flow inside the aneurysm with overlapping FDs compared to a single FD. The qualitative and quantitative investigations are meaningful for the clinical outcomes of overlapped FD deployment.
BIOENGINEERING-BASEL
(2021)
Article
Chemistry, Multidisciplinary
Sima Baheri Islami, Mike Wesolowski, William Revell, Xiongbiao Chen
Summary: The study introduces a method of visualizing computational fluid dynamics simulations of cerebral aneurysm treatment using virtual reality. By developing a method to convert numerical data into three-dimensional objects in virtual reality, neurosurgeons and patients can make better decisions about treatment devices and improve the pre-treatment consulting process.
APPLIED SCIENCES-BASEL
(2021)
Article
Biology
Janneck Stahl, Laurel Morgan Miller Marsh, Maximilian Thormann, Andreas Ding, Sylvia Saalfeld, Daniel Behme, Philipp Berg
Summary: This study analyzed the hemodynamics of ten intracranial aneurysm patients treated with a novel flow diverter device. The results showed that the treatment led to a reduction in blood flow, promoting thrombus formation.
COMPUTERS IN BIOLOGY AND MEDICINE
(2023)
Article
Clinical Neurology
Bart M. W. Cornelissen, Eva L. Leemans, Cornelis H. Slump, Rene van den Berg, Henk A. Marquering, Charles B. L. M. Majoie
Summary: This study investigates how hemodynamic characteristics change over the course of aneurysm growth. They found that wall shear stress values generally decrease after growth, but there is significant variability in hemodynamic changes between aneurysms.
JOURNAL OF NEUROSURGERY
(2022)
Article
Geriatrics & Gerontology
Xinyu Liang, Fei Peng, Yunchu Yao, Yuting Yang, Aihua Liu, Duanduan Chen
Summary: This study investigated the pathophysiological mechanisms of intracranial fusiform aneurysms (IFAs) based on the characteristics of aneurysm wall enhancement (AWE), hemodynamics, and morphology. The results showed significant associations between AWE and aneurysm size as well as hemodynamic parameters. Further research is needed to understand the underlying pathological mechanisms of different types of fusiform aneurysms.
FRONTIERS IN AGING NEUROSCIENCE
(2023)
Article
Computer Science, Interdisciplinary Applications
Levente Sandor, Gyorgy Paal
Summary: This study examines the impact of linear and quadratic hydrodynamic resistance parameters on the flow of five patient-specific sidewall aneurysms. Through 125 blood flow simulations, a Darcy-Forcheimer porous layer approach based on real-life stent characteristics was used. The study found that the time- and space-averaged velocity magnitudes were strongly influenced by the linear coefficient, while the quadratic coefficients had a minor effect on the low-velocity flow in the aneurysm sac and neck region.
COMPUTER METHODS IN BIOMECHANICS AND BIOMEDICAL ENGINEERING
(2023)
Article
Engineering, Biomedical
Nhien Tran-Nguyen, Francesca Condemi, Andrew Yan, Stephen Fremes, Piero Triverio, Laura Jimenez-Juan
Summary: This prospective study used computational fluid dynamics to investigate how graft hemodynamics may vary among different types of grafts one month after coronary artery bypass graft (CABG) surgery. The study found differences in abnormal wall shear stress area among different types of grafts, suggesting a possible influence on long-term graft failure rates.
ANNALS OF BIOMEDICAL ENGINEERING
(2022)
Article
Clinical Neurology
Shintaro Nakajima, Shinichiro Sugiyama, Hidenori Oishi, Kenichi Sato, Yasushi Matsumoto, Kuniyasu Niizuma, Miki Fujimura, Teiji Tominaga
Summary: The study demonstrated the usefulness of CFD analysis in diagnosing atherosclerotic changes in large CCAs, which may affect therapeutic response following flow diversion. Post-CFD visualization showed that intra-aneurysmal swirling flow prolonged blood residence time under conditions of small inlet flow rates compared to aneurysmal volume.
Article
Clinical Neurology
Soichiro Fujimura, Kazutoshi Tanaka, Hiroyuki Takao, Takuma Okudaira, Hirokazu Koseki, Akiko Hasebe, Takashi Suzuki, Yuya Uchiyama, Toshihiro Ishibashi, Katharina Otani, Kostadin Karagiozov, Koji Fukudome, Motoharu Hayakawa, Makoto Yamamoto, Yuichi Murayama
Summary: This study investigates the relationship between aneurysm initiation and hemodynamic factors using angiographic images of patients with cerebral aneurysms taken before and after an aneurysm formation. The findings suggest that aneurysm initiation is more likely to occur in areas with high tensile forces acting on the vessel wall and high total pressure loss.
JOURNAL OF NEUROSURGERY
(2022)
Article
Engineering, Biomedical
Yoke Rung Wong, Chi Wei Ong, Alyssa LiYu Toh, Einly Lim, Pei Ho, Hwa Liang Leo
Summary: A novel method for measuring the real-time input flow impedance of thoracic aorta aneurysm (TAA) was developed in this study. The unique features of real-time input flow impedance were extracted to correlate with TAA formation. The proposed fluid mechanics model has the potential to analyze aneurysmal diseases in real-time.
BIOMEDICAL SIGNAL PROCESSING AND CONTROL
(2021)
Article
Chemistry, Multidisciplinary
Jhon Jasper Apan, Lemmuel Tayo, Jaime Honra
Summary: The study aimed to optimize the hemodynamics of bypass grafts to prolong graft patency. By inducing spiral flow using an internal ridge, it was found that smaller anastomosis angles can optimize graft performance by reducing pressure drop and abnormal shear stresses in the host artery. The modified design outperformed conventional grafts due to increased shear stress, which has atheroprotective benefits. These findings highlight the importance of understanding and optimizing different geometric properties in designing long-lasting bypass grafts.
APPLIED SCIENCES-BASEL
(2023)
Article
Clinical Neurology
Yongsheng Liu, Guinan Jiang, Feng Wang, Xiangbo An
Summary: This study aimed to investigate the hemodynamic changes of distal arterial trees and factors contributing to hyperperfusion after large intracranial aneurysms obliteration. Results showed that pressure and flow velocity of distal arterial trees increased significantly after aneurysm obliteration, with the aneurysmal angle being a key factor in pressure increase.
FRONTIERS IN NEUROLOGY
(2021)
Article
Mechanics
Takashi Suzuki, Hiroyuki Takao, Tomoaki Suzuki, Shunsuke Hataoka, Tomonobu Kodama, Ken Aoki, Katharina Otani, Toshihiro Ishibashi, Hideki Yamamoto, Yuichi Murayama, Makoto Yamamoto
Summary: A practical non-Newtonian viscosity model was employed to estimate patient-specific apparent viscosities based on hematocrit values, with results showing similarities to those obtained by patient-specific viscosity models in CFD analyses. The differences between calculated parameters using different viscosity models were verified, with the Hct model showing reliable results compared to other simplified models.
JOURNAL OF NON-NEWTONIAN FLUID MECHANICS
(2021)
Article
Engineering, Biomedical
Piotr Reorowicz, Zbigniew Tyfa, Damian Obidowski, Karol Wisniewski, Ludomir Stefanczyk, Krzysztof Jozwik, Michael Lee Levy
Summary: The Flow Diverter is a treatment method for fusiform aneurysms, commonly used for cerebral vascular anomalies but not for aortic aneurysms. Numerical simulation in a patient-specific model of abdominal aortic aneurysms allowed investigation and visualization of blood hemodynamics before and after stent implantation. The Flow Diverter stent significantly changed the flow pattern in the aneurysm region but did not affect blood flow to the renal arteries.
BIOCYBERNETICS AND BIOMEDICAL ENGINEERING
(2022)