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Fan X, Zhang A, Zheng Q, Li P, Wang Y, He L, Xue Y, Chen W, Wu X, Zhao Y, Wang Y. The biomechanical effects of different membrane layer structures and material constitutive modeling on patient-specific cerebral aneurysms. Front Bioeng Biotechnol 2024; 11:1323266. [PMID: 38288243 PMCID: PMC10822973 DOI: 10.3389/fbioe.2023.1323266] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2023] [Accepted: 12/29/2023] [Indexed: 01/31/2024] Open
Abstract
The prevention, control and treatment of cerebral aneurysm (CA) has become a common concern of human society, and by simulating the biomechanical environment of CA using finite element analysis (FEA), the risk of aneurysm rupture can be predicted and evaluated. The target models of the current study are mainly idealized single-layer linear elastic cerebral aneurysm models, which do not take into account the effects of the vessel wall structure, material constitution, and structure of the real CA model on the mechanical parameters. This study proposes a reconstruction method for patient-specific trilaminar CA structural modeling. Using two-way fluid-structure interaction (FSI), we comparatively analyzed the effects of the differences between linear and hyperelastic materials and three-layer and single-layer membrane structures on various hemodynamic parameters of the CA model. It was found that the numerical effects of the different CA membrane structures and material constitution on the stresses and wall deformations were obvious, but does not affect the change in its distribution pattern and had little effect on the blood flow patterns. For the same material constitution, the stress of the three-layer membrane structure were more than 10.1% larger than that of the single-layer membrane structure. For the same membrane structure, the stress of the hyperelastic material were more than 5.4% larger than that of the linear elastic material, and the displacement of the hyperelastic material is smaller than that of the linear elastic material by about 20%. And the maximum value of stress occurred in the media, and the maximum displacement occurred in the intima. In addition, the upper region of the tumor is the maximum rupture risk region for CA, and the neck of the tumor and the bifurcation of the artery are also the sub-rupture risk regions to focus on. This study can provide data support for the selection of model materials for CA simulation and analysis, as well as a theoretical basis for clinical studies and subsequent research methods.
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Affiliation(s)
- Xuanze Fan
- College of Biomedical Engineering, Taiyuan University of Technology, Taiyuan, China
| | - Aohua Zhang
- College of Biomedical Engineering, Taiyuan University of Technology, Taiyuan, China
| | - Qingli Zheng
- College of Biomedical Engineering, Taiyuan University of Technology, Taiyuan, China
| | - Pengcui Li
- Shanxi Provincial Key Laboratory for Repair of Bone and Soft Tissue Injury, Taiyuan, China
| | - Yanqin Wang
- College of Biomedical Engineering, Taiyuan University of Technology, Taiyuan, China
| | - Liming He
- Shanxi Bethune Hospital, Shanxi Academy of Medical Sciences, Tongji Shanxi Hospital, Third Hospital of Shanxi Medical University, Taiyuan, China
| | - Yanru Xue
- College of Biomedical Engineering, Taiyuan University of Technology, Taiyuan, China
- Shanxi Bethune Hospital, Shanxi Academy of Medical Sciences, Tongji Shanxi Hospital, Third Hospital of Shanxi Medical University, Taiyuan, China
| | - Weiyi Chen
- College of Biomedical Engineering, Taiyuan University of Technology, Taiyuan, China
| | - Xiaogang Wu
- College of Biomedical Engineering, Taiyuan University of Technology, Taiyuan, China
- Shanxi Bethune Hospital, Shanxi Academy of Medical Sciences, Tongji Shanxi Hospital, Third Hospital of Shanxi Medical University, Taiyuan, China
| | | | - Yonghong Wang
- Shanxi Bethune Hospital, Shanxi Academy of Medical Sciences, Tongji Shanxi Hospital, Third Hospital of Shanxi Medical University, Taiyuan, China
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2
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Kuyanova J, Dubovoi A, Fomichev A, Khelimskii D, Parshin D. Hemodynamics of vascular shunts: trends, challenges, and prospects. Biophys Rev 2023; 15:1287-1301. [PMID: 37975016 PMCID: PMC10643646 DOI: 10.1007/s12551-023-01149-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2023] [Accepted: 09/12/2023] [Indexed: 11/19/2023] Open
Abstract
Vascular bypass surgery takes a significant place in the treatment of vascular disease. According to various assessments, this type of surgery is associated with almost 20 % of all vascular surgery episodes (up to 23 % according to the Federal Neurosurgical Center of Novosibirsk). Even though the problem of using of vascular grafts is obvious and natural, many problems associated with them are not still elucidated. From the mechanics' point of view, a vascular bypass is a converging or diverging tee, and the functioning of such structures still does not have strict mathematical formulations and proofs in the general case, which forces many researchers to solve specific engineering problems associated with shunting. Mathematical modeling, which is the gold standard for virtual simulations of industrial and medical problems, faces great difficulties and limitations in solving problems for vascular bypasses. Complications in the treatment of the vascular disease may follow the difficulties in mathematical modeling, and the price can be a cardiac arrest or a stroke. This work is devoted to the main aspects of the medical application of vascular bypasses and their functioning as a mechanical system, as well the mathematical aspects of their possible setup.
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Affiliation(s)
- Julia Kuyanova
- Department, Lavrentyev Institute of Hydrodynamics SB RAS, Ac. Lavrentieva ave., Novosibirsk, 630090 Russian Federation
| | - Andrei Dubovoi
- Department, FSBI “Federal Neurosurgical Center”, Nemirovicha-Danchenko st., Novosibirsk, 630087 Russian Federation
| | - Aleksei Fomichev
- Department, Meshalkin National Medical Research Center, Rechkunovskaya st., Novosibirsk, 610101 Russian Federation
| | - Dmitrii Khelimskii
- Department, Meshalkin National Medical Research Center, Rechkunovskaya st., Novosibirsk, 610101 Russian Federation
| | - Daniil Parshin
- Department, Lavrentyev Institute of Hydrodynamics SB RAS, Ac. Lavrentieva ave., Novosibirsk, 630090 Russian Federation
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3
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Wang X, Carpenter HJ, Ghayesh MH, Kotousov A, Zander AC, Amabili M, Psaltis PJ. A review on the biomechanical behaviour of the aorta. J Mech Behav Biomed Mater 2023; 144:105922. [PMID: 37320894 DOI: 10.1016/j.jmbbm.2023.105922] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2023] [Revised: 05/14/2023] [Accepted: 05/20/2023] [Indexed: 06/17/2023]
Abstract
Large aortic aneurysm and acute and chronic aortic dissection are pathologies of the aorta requiring surgery. Recent advances in medical intervention have improved patient outcomes; however, a clear understanding of the mechanisms leading to aortic failure and, hence, a better understanding of failure risk, is still missing. Biomechanical analysis of the aorta could provide insights into the development and progression of aortic abnormalities, giving clinicians a powerful tool in risk stratification. The complexity of the aortic system presents significant challenges for a biomechanical study and requires various approaches to analyse the aorta. To address this, here we present a holistic review of the biomechanical studies of the aorta by categorising articles into four broad approaches, namely theoretical, in vivo, experimental and combined investigations. Experimental studies that focus on identifying mechanical properties of the aortic tissue are also included. By reviewing the literature and discussing drawbacks, limitations and future challenges in each area, we hope to present a more complete picture of the state-of-the-art of aortic biomechanics to stimulate research on critical topics. Combining experimental modalities and computational approaches could lead to more comprehensive results in risk prediction for the aortic system.
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Affiliation(s)
- Xiaochen Wang
- School of Electrical and Mechanical Engineering, The University of Adelaide, Adelaide, South Australia 5005, Australia.
| | - Harry J Carpenter
- School of Electrical and Mechanical Engineering, The University of Adelaide, Adelaide, South Australia 5005, Australia
| | - Mergen H Ghayesh
- School of Electrical and Mechanical Engineering, The University of Adelaide, Adelaide, South Australia 5005, Australia.
| | - Andrei Kotousov
- School of Electrical and Mechanical Engineering, The University of Adelaide, Adelaide, South Australia 5005, Australia
| | - Anthony C Zander
- School of Electrical and Mechanical Engineering, The University of Adelaide, Adelaide, South Australia 5005, Australia
| | - Marco Amabili
- Department of Mechanical Engineering, McGill University, Montreal H3A 0C3, Canada
| | - Peter J Psaltis
- Adelaide Medical School, The University of Adelaide, Adelaide, South Australia 5005, Australia; Department of Cardiology, Central Adelaide Local Health Network, Adelaide, South Australia 5000, Australia; Vascular Research Centre, Heart Health Theme, South Australian Health & Medical Research Institute (SAHMRI), Adelaide, South Australia 5000, Australia
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4
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Syed F, Khan S, Toma M. Modeling Dynamics of the Cardiovascular System Using Fluid-Structure Interaction Methods. BIOLOGY 2023; 12:1026. [PMID: 37508455 PMCID: PMC10376821 DOI: 10.3390/biology12071026] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/01/2023] [Revised: 07/07/2023] [Accepted: 07/18/2023] [Indexed: 07/30/2023]
Abstract
Using fluid-structure interaction algorithms to simulate the human circulatory system is an innovative approach that can provide valuable insights into cardiovascular dynamics. Fluid-structure interaction algorithms enable us to couple simulations of blood flow and mechanical responses of the blood vessels while taking into account interactions between fluid dynamics and structural behaviors of vessel walls, heart walls, or valves. In the context of the human circulatory system, these algorithms offer a more comprehensive representation by considering the complex interplay between blood flow and the elasticity of blood vessels. Algorithms that simulate fluid flow dynamics and the resulting forces exerted on vessel walls can capture phenomena such as wall deformation, arterial compliance, and the propagation of pressure waves throughout the cardiovascular system. These models enhance the understanding of vasculature properties in human anatomy. The utilization of fluid-structure interaction methods in combination with medical imaging can generate patient-specific models for individual patients to facilitate the process of devising treatment plans. This review evaluates current applications and implications of fluid-structure interaction algorithms with respect to the vasculature, while considering their potential role as a guidance tool for intervention procedures.
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Affiliation(s)
- Faiz Syed
- College of Osteopathic Medicine, New York Institute of Technology, Northern Boulevard, Old Westbury, NY 11568, USA
| | - Sahar Khan
- College of Osteopathic Medicine, New York Institute of Technology, Northern Boulevard, Old Westbury, NY 11568, USA
| | - Milan Toma
- College of Osteopathic Medicine, New York Institute of Technology, Northern Boulevard, Old Westbury, NY 11568, USA
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5
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Arslan AC, Salman HE. Effect of Intraluminal Thrombus Burden on the Risk of Abdominal Aortic Aneurysm Rupture. J Cardiovasc Dev Dis 2023; 10:233. [PMID: 37367398 DOI: 10.3390/jcdd10060233] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2023] [Revised: 05/19/2023] [Accepted: 05/23/2023] [Indexed: 06/28/2023] Open
Abstract
Abdominal aortic aneurysm (AAA) is a critical health disorder, where the abdominal aorta dilates more than 50% of its normal diameter. Enlargement in abdominal aorta alters the hemodynamics and flow-induced forces on the AAA wall. Depending on the flow conditions, the hemodynamic forces on the wall may result in excessive mechanical stresses that lead to AAA rupture. The risk of rupture can be predicted using advanced computational techniques such as computational fluid dynamics (CFD) and fluid-structure interaction (FSI). For a reliable rupture risk assessment, formation of intraluminal thrombus (ILT) and uncertainty in arterial material properties should be taken into account, mainly due to the patient-specific differences and unknowns in AAAs. In this study, AAA models are computationally investigated by performing CFD simulations combined with FSI analysis. Various levels of ILT burdens are artificially generated in a realistic AAA geometry, and the peak effective stresses are evaluated to elucidate the effect of material models and ILT formation. The results indicate that increasing the ILT burden leads to lowered effective stresses on the AAA wall. The material properties of the artery and ILT are also effective on the stresses; however, these effects are limited compared to the effect of ILT volume in the AAA sac.
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Affiliation(s)
- Aykut Can Arslan
- Department of Mechanical Engineering, TOBB University of Economics and Technology, Ankara 06530, Turkey
| | - Huseyin Enes Salman
- Department of Mechanical Engineering, TOBB University of Economics and Technology, Ankara 06530, Turkey
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6
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Haniel J, Yiu BYS, Chee AJY, Huebner R, Yu ACH. Efficacy of ultrasound vector flow imaging in tracking omnidirectional pulsatile flow. Med Phys 2023; 50:1699-1714. [PMID: 36546560 DOI: 10.1002/mp.16168] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2022] [Revised: 11/21/2022] [Accepted: 11/23/2022] [Indexed: 12/24/2022] Open
Abstract
BACKGROUND Ultrasound vector flow imaging (VFI) shows potential as an emerging non-invasive modality for time-resolved flow mapping. However, its efficacy in tracking multidirectional pulsatile flow with temporal resolvability has not yet been systematically evaluated because of the lack of an appropriate test protocol. PURPOSE We present the first systematic performance investigation of VFI in tracking pulsatile flow in a meticulously designed scenario with time-varying, omnidirectional flow fields (with flow angles from 0° to 360°). METHODS Ultrasound VFI was performed on a three-loop spiral flow phantom (4 mm diameter; 5 mm pitch) that was configured to operate under pulsatile flow conditions (10 ml/s peak flow rate; 1 Hz pulse rate; carotid pulse shape). The spiral lumen geometry was designed to simulate recirculatory flow dynamics observed in the heart and in curvy blood vessel segments such as the carotid bulb. The imaging sequence was based on steered plane wave pulsing (-10°, 0°, +10° steering angles; 5 MHz imaging frequency; 3.3 kHz interleaved pulse repetition frequency). VFI's pulsatile flow estimation performance and its ability to detect secondary flow were comparatively assessed against flow fields derived from computational fluid dynamics (CFD) simulations that included consideration of fluid-structure interactions (FSI). The mean percentage error (MPE) and the coefficient of determination (R2 ) were computed to assess the correspondence of the velocity estimates derived from VFI and CFD-FSI simulations. In addition, VFI's efficacy in tracking pulse waves was analyzed with respect to pressure transducer measurements made at the phantom's inlet and outlet. RESULTS Pulsatile flow patterns rendered by VFI agreed with the flow profiles computed from CFD-FSI simulations (average MPE: -5.3%). The shape of the VFI-measured velocity magnitude profile generally matched the inlet flow profile. High correlation exists between VFI measurements and simulated flow vectors (lateral velocity: R2 = 0.8; axial velocity R2 = 0.89; beam-flow angle: R2 = 0.98; p < 0.0001 for all three quantities). VFI was found to be capable of consistently tracking secondary flow. It also yielded pulse wave velocity (PWV) estimates (5.72 ± 1.02 m/s) that, on average, are within 6.4% of those obtained from pressure transducer measurements (6.11 ± 1.15 m/s). CONCLUSION VFI can consistently track omnidirectional pulsatile flow on a time-resolved basis. This systematic investigation serves well as a quality assurance test of VFI.
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Affiliation(s)
- Jonathas Haniel
- Schlegel Research Institute for Aging and Department of Electrical & Computer Engineering, University of Waterloo, Waterloo, Ontario, Canada
- Department of Mechanical Engineering, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
| | - Billy Y S Yiu
- Schlegel Research Institute for Aging and Department of Electrical & Computer Engineering, University of Waterloo, Waterloo, Ontario, Canada
| | - Adrian J Y Chee
- Schlegel Research Institute for Aging and Department of Electrical & Computer Engineering, University of Waterloo, Waterloo, Ontario, Canada
| | - Rudolf Huebner
- Department of Mechanical Engineering, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
| | - Alfred C H Yu
- Schlegel Research Institute for Aging and Department of Electrical & Computer Engineering, University of Waterloo, Waterloo, Ontario, Canada
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7
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Ramella A, Migliavacca F, Rodriguez Matas JF, Mandigers TJ, Bissacco D, Domanin M, Trimarchi S, Luraghi G. Applicability assessment for in-silico patient-specific TEVAR procedures. J Biomech 2023; 146:111423. [PMID: 36584506 DOI: 10.1016/j.jbiomech.2022.111423] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2022] [Revised: 12/05/2022] [Accepted: 12/23/2022] [Indexed: 12/25/2022]
Abstract
Thoracic Endovascular Aortic Repair (TEVAR) is a minimally invasive technique to treat thoracic aorta pathologies and consists of placing a self-expandable stent-graft into the pathological region to restore the vessel lumen and recreate a more physiological condition. Exhaustive computational models, namely the finite element analysis, can be implemented to reproduce the clinical procedure. In this context, numerical models, if used for clinical applications, must be reliable and the simulation credibility should be proved to predict clinical procedure outcomes or to build in-silico clinical trials. This work aims first at applying a previously validated TEVAR methodology to a patient-specific case. Then, defining the TEVAR procedure performed on a patient population as the context of use, the overall applicability of the TEVAR modeling is assessed to demonstrate the reliability of the model itself following a step-by-step method based on the ASME V&V40 protocol. Validation evidence sources are identified for the specific context of use and adopted to demonstrate the applicability of the numerical procedure, thereby answering a question of interest that evaluates the deployed stent-graft configuration in the vessel.
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Affiliation(s)
- Anna Ramella
- Department of Chemistry, Materials and Chemical Engineering, Politecnico di Milano, Piazza L. da Vinci 32, 20133 Milan, Italy
| | - Francesco Migliavacca
- Department of Chemistry, Materials and Chemical Engineering, Politecnico di Milano, Piazza L. da Vinci 32, 20133 Milan, Italy
| | - Jose Felix Rodriguez Matas
- Department of Chemistry, Materials and Chemical Engineering, Politecnico di Milano, Piazza L. da Vinci 32, 20133 Milan, Italy
| | - Tim J Mandigers
- Unit of Vascular Surgery, I.R.C.C.S. Fondazione Cà Granda Policlinico Milano, Via Francesco Sforza 35, Milan, Italy
| | - Daniele Bissacco
- Unit of Vascular Surgery, I.R.C.C.S. Fondazione Cà Granda Policlinico Milano, Via Francesco Sforza 35, Milan, Italy
| | - Maurizio Domanin
- Unit of Vascular Surgery, I.R.C.C.S. Fondazione Cà Granda Policlinico Milano, Via Francesco Sforza 35, Milan, Italy
| | - Santi Trimarchi
- Unit of Vascular Surgery, I.R.C.C.S. Fondazione Cà Granda Policlinico Milano, Via Francesco Sforza 35, Milan, Italy
| | - Giulia Luraghi
- Department of Chemistry, Materials and Chemical Engineering, Politecnico di Milano, Piazza L. da Vinci 32, 20133 Milan, Italy.
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8
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Chen B, Tao W, Li S, Zeng M, Zhang L, Huang Z, Chen F. Medial Gap: A Structural Factor at the Arterial Bifurcation Aggravating Hemodynamic Insult. J Neuropathol Exp Neurol 2022; 81:282-290. [PMID: 35312777 DOI: 10.1093/jnen/nlac017] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Previous studies have reported that intracranial aneurysms frequently occur adjacent to the medial gap. However, the role of the medial gap in aneurysm formation is controversial. We designed this study to explore the potential role of the medial gap in aneurysm formation. Widened artery bifurcations with or without medial gaps were microsurgically created and pathologically stained in the carotid arteries of 30 rats. Numerical artery bifurcation models were constructed, and bidirectional fluid-solid interaction analyses were performed. Animal experiments showed that the apexes of widened bifurcations with a medial gap were prone to being insulted by blood flow compared to those without a medial gap. The bidirectional fluid-solid interaction analyses indicated that artery bifurcations with the medial gap exhibited higher wall shear stress (WSS) and von Mises stress (VMS) at the apex of the bifurcation. The disparity of stress between the gap and no-gap model was larger for widened bifurcations, peaking at 180° with a maximum of 1.9 folds. The maximum VMS and relatively high WSS were located at the junction between the medial gap and the adjacent arterial wall. Our results suggest that the medial gap at the widened arterial bifurcation may promote aneurysm formation.
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Affiliation(s)
- Bo Chen
- From the Department of Neurosurgery, Xiangya Hospital, Central South University, Changsha, Hunan, China.,National Clinical Research Center for Geriatric Disorders, Xiangya Hospital, Central South University, Changsha, Hunan, China
| | - Wengui Tao
- From the Department of Neurosurgery, Xiangya Hospital, Central South University, Changsha, Hunan, China.,National Clinical Research Center for Geriatric Disorders, Xiangya Hospital, Central South University, Changsha, Hunan, China
| | - Shifu Li
- From the Department of Neurosurgery, Xiangya Hospital, Central South University, Changsha, Hunan, China.,National Clinical Research Center for Geriatric Disorders, Xiangya Hospital, Central South University, Changsha, Hunan, China
| | - Ming Zeng
- From the Department of Neurosurgery, Xiangya Hospital, Central South University, Changsha, Hunan, China.,National Clinical Research Center for Geriatric Disorders, Xiangya Hospital, Central South University, Changsha, Hunan, China
| | - Liyang Zhang
- From the Department of Neurosurgery, Xiangya Hospital, Central South University, Changsha, Hunan, China.,National Clinical Research Center for Geriatric Disorders, Xiangya Hospital, Central South University, Changsha, Hunan, China
| | - Zheng Huang
- From the Department of Neurosurgery, Xiangya Hospital, Central South University, Changsha, Hunan, China.,National Clinical Research Center for Geriatric Disorders, Xiangya Hospital, Central South University, Changsha, Hunan, China
| | - Fenghua Chen
- From the Department of Neurosurgery, Xiangya Hospital, Central South University, Changsha, Hunan, China.,National Clinical Research Center for Geriatric Disorders, Xiangya Hospital, Central South University, Changsha, Hunan, China
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9
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Shamloo A, Ebrahimi S, Ghorbani G, Alishiri M. Targeted drug delivery of magnetic microbubble for abdominal aortic aneurysm: an in silico study. Biomech Model Mechanobiol 2022; 21:735-753. [PMID: 35079930 DOI: 10.1007/s10237-022-01559-4] [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: 08/03/2021] [Accepted: 01/06/2022] [Indexed: 11/02/2022]
Abstract
Targeted drug delivery (TDD) to abdominal aortic aneurysm (AAA) using a controlled and efficient approach has recently been a significant challenge. In this study, by using magnetic microbubbles (MMBs) under a magnetic field, we investigated the MMBs performance in TDD to AAA based on the amount of surface density of MMBs (SDMM) adhered to the AAA lumen. The results showed that among the types of MMBs studied in the presence of the magnetic field, micromarkers are the best type of microbubble with a -[Formula: see text] increase in SDMM adhered to the critical area of AAA. The results show that applying a magnetic field causes the amount of SDMM adhered to the whole area of AAA to increase -[Formula: see text] times compared to the condition in which the magnetic field is absent. This optimal and maximum value occurs for Definity MMBs with - 3.3 μm diameter. Applying a magnetic field also increases the adhesion surface density by - [Formula: see text], - [Formula: see text], and -[Formula: see text] times for the Micromarker, Optison, and Sonovue microbubbles, respectively, relative to the condition in which the magnetic field is absent. It was shown that using MBBs under magnetic field has the best performance in delivery to AAA for patients with negative inlet blood flow. Also, we have exposed that in an efficient TDD to AAA using MMBs, decreasing the density of MMBs increases drug delivery efficiency and performance. When density is - [Formula: see text], there is the highest difference (about - 75%) between the SDMM adhered to AAA in the presence of a magnetic field and in the absence of a magnetic field.
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Affiliation(s)
- Amir Shamloo
- Nano-Bioengineering Lab, School of Mechanical Engineering, Sharif University of Technology , Azadi Ave., Tehran, Iran. .,Stem Cell and Regenerative Medicine Center, Sharif University of Technology, Tehran, Iran.
| | - Sina Ebrahimi
- Nano-Bioengineering Lab, School of Mechanical Engineering, Sharif University of Technology , Azadi Ave., Tehran, Iran.,Stem Cell and Regenerative Medicine Center, Sharif University of Technology, Tehran, Iran
| | - Ghazal Ghorbani
- Nano-Bioengineering Lab, School of Mechanical Engineering, Sharif University of Technology , Azadi Ave., Tehran, Iran.,Stem Cell and Regenerative Medicine Center, Sharif University of Technology, Tehran, Iran
| | - Mojgan Alishiri
- Nano-Bioengineering Lab, School of Mechanical Engineering, Sharif University of Technology , Azadi Ave., Tehran, Iran.,Stem Cell and Regenerative Medicine Center, Sharif University of Technology, Tehran, Iran
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10
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Zhang Y, Fan J, Xiu Y, Zhang L, Chen G, Fan J, Lin X, Ding C, Feng M, Wang R, Liu Y. Numerical simulation flow dynamics of an intracranial aneurysm. Biomed Mater Eng 2021; 33:123-129. [PMID: 34633312 DOI: 10.3233/bme-211270] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
BACKGROUND Computational fluid dynamics provides a new method for the study of the blood flow characteristics of the formation and development of intracranial aneurysms. OBJECTIVE To compare blood flow characteristics between the healthy internal carotid artery and normal intracranial aneurysms. METHODS The internal carotid arteries were simulated to obtain hemodynamic parameters in one patient. RESULTS The internal carotid artery associated with aneurysm presents low wall shear stress, high oscillatory shear index, and high particle retention time compared with the normal internal carotid artery. CONCLUSIONS There are differences in blood flow between the normal internal carotid artery and intracranial aneurysm. The vortex of the aneurysm will produce turbulence, indicating that it is unstable, which results in the growth and rupture of the aneurysm.
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Affiliation(s)
- Yang Zhang
- Laboratory of the Second Hospital Attached to Mudanjiang Medical University, Heilongjiang, Mudanjiang, China.,Department of Immunology, Mudanjiang Medical University, Heilongjiang, Mudanjiang, China
| | - Junjie Fan
- School of Health Management, Mudanjiang Medical University, Heilongjiang, Mudanjiang, China
| | - Yunxia Xiu
- Laboratory of the Second Hospital Attached to Mudanjiang Medical University, Heilongjiang, Mudanjiang, China
| | - Luyao Zhang
- Department of Immunology, Mudanjiang Medical University, Heilongjiang, Mudanjiang, China
| | - Guangxin Chen
- School of Imaging, Mudanjiang Medical University, Heilongjiang, Mudanjiang, China
| | - Jinyu Fan
- The First Clinical Medical School, Mudanjiang Medical University, Heilongjiang, Mudanjiang, China
| | - Xiao Lin
- Department of Immunology, Mudanjiang Medical University, Heilongjiang, Mudanjiang, China
| | - Chen Ding
- Department of Immunology, Mudanjiang Medical University, Heilongjiang, Mudanjiang, China
| | - Mingming Feng
- School of Imaging, Mudanjiang Medical University, Heilongjiang, Mudanjiang, China
| | - Ruliang Wang
- Department of Imaging, Hongqi Hospital Attached to Mudanjiang Medical University, Heilongjiang, Mudanjiang, China
| | - Yang Liu
- The Academic Affairs Office of Mudanjiang Medical University, Heilongjiang, Mudanjiang, China
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11
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Ebrahimi S, Vatani P, Amani A, Shamloo A. Drug delivery performance of nanocarriers based on adhesion and interaction for abdominal aortic aneurysm treatment. Int J Pharm 2020; 594:120153. [PMID: 33301866 DOI: 10.1016/j.ijpharm.2020.120153] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2020] [Revised: 12/03/2020] [Accepted: 12/03/2020] [Indexed: 10/22/2022]
Abstract
Targeted drug delivery using nanocarriers (NCs) is one of the novel techniques that has recently been used to improve drug delivery to the Abdominal aortic aneurysm (AAA) disease. The purpose of this study is to evaluate the surface density of NCs (SDNC) adhered via ligand-receptor binding to the inner wall of AAA. For this purpose, fluid-structure interaction (FSI) analysis was first performed for the patient-specific and ideal AAA models. Then, by injecting NCs into the aortic artery, the values of SDNC adhered to and interacted with AAA wall were obtained. Two types of NCs, liposomes, and solid particles in four different diameters, were used to investigate the effect of the diameter and the type of NCs on the drug delivery. Additionally, the effect of the number of the injected NCs to the artery on the values of SDNC adhered to and interacted with AAA wall was investigated. The simulation results showed that the interaction and adhesion values of SDNC for Liposome nanoparticles were higher than the ones for the solid particles. Furthermore, as the diameter of NCs increases, the values of SDNC adhered to AAA wall increase, but the values of SDNC interacted with the inner wall of AAA decrease. In the low number of inserted NCs in the artery (1000 NCs), the interaction and adhesion values of SDNC were very slight, and by increasing the number of NCs inserted into the artery, the drug delivery was improved. By examining different AAA models, it was found that the complexity of the shape of AAA has a minor effect on the pattern of increase or decrease of the values of SDNC adhered to and interacted with AAA wall.This study's findings can improve the understanding of NCs design and propose the appropriate amount of their injection into various AAA models.
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Affiliation(s)
- Sina Ebrahimi
- School of Mechanical Engineering, Sharif University of Technology, Tehran, Iran
| | - Pouyan Vatani
- School of Mechanical Engineering, Sharif University of Technology, Tehran, Iran
| | - Ali Amani
- School of Mechanical Engineering, Sharif University of Technology, Tehran, Iran
| | - Amir Shamloo
- School of Mechanical Engineering, Sharif University of Technology, Tehran, Iran.
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12
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de Lucio M, García MF, García JD, Rodríguez LER, Marcos FÁ. On the importance of tunica intima in the aging aorta: a three-layered in silico model for computing wall stresses in abdominal aortic aneurysms. Comput Methods Biomech Biomed Engin 2020; 24:467-484. [PMID: 33090043 DOI: 10.1080/10255842.2020.1836167] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
Layer-specific experimental data for human aortic tissue suggest that, in aged arteries and arteries with non-atherosclerotic intimal thickening, the innermost layer of the aorta increases significantly its stiffness and thickness, becoming load-bearing. However, there are very few computational studies of abdominal aortic aneurysms (AAAs) that take into account the mechanical contribution of the three layers that comprise the aneurysmal tissue. In this paper, a three-layered finite element model is proposed from the simplest uniaxial stress state to geometrically parametrized models of AAAs with different asymmetry values. Comparisons are made between a three-layered artery wall and a mono-layered intact artery, which represents the complex behavior of the aggregate adventitia-media-intima in a single layer with averaged mechanical properties. Likewise, the response of our idealized geometries is compared with similar experimental and numerical models. Finally, the mechanical contributions of adventitia, media and intima are analyzed for the three-layered aneurysms through the evaluation of the mean stress absorption percentage. Results show the relevance and necessity of considering the inclusion of tunica intima in multi-layered models of AAAs for getting accurate results in terms of peak wall stresses and displacements.
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Affiliation(s)
- Mario de Lucio
- School of Mechanical Engineering, Purdue University, West Lafayette, IN, USA
| | - Marcos Fernández García
- Structural Impact Laboratory (SIMLab) and Centre for Advanced Structural Analysis (CASA), Department of Structural Engineering, Norwegian University of Science and Technology (NTNU), Trondheim, Norway
| | - Jacobo Díaz García
- Structural Mechanics Group, School of Civil Engineering, Universidade da Coruña, A Coruña, Spain
| | | | - Francisco Álvarez Marcos
- Angiology and Vascular Surgery Department, Asturias University Central Hospital (HUCA), Oviedo, Spain
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13
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Shamloo A, Ebrahimi S, Amani A, Fallah F. Targeted Drug Delivery of Microbubble to Arrest Abdominal Aortic Aneurysm Development: A Simulation Study Towards Optimized Microbubble Design. Sci Rep 2020; 10:5393. [PMID: 32214205 PMCID: PMC7096410 DOI: 10.1038/s41598-020-62410-3] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2019] [Accepted: 03/12/2020] [Indexed: 01/10/2023] Open
Abstract
Abdominal aortic aneurysm (AAA) is an irreversible bulge in the artery with higher prevalence among the elderlies. Increase of the aneurysm diameter by time is a fatal phenomenon which will lead to its sidewall rupture. Invasive surgical treatments are vital in preventing from AAA development. These approaches however have considerable side effects. Targeted drug delivery using microbubbles (MBs) has been recently employed to suppress the AAA growth. The present study is aimed to investigate the surface adhesion of different types of drug-containing MBs to the inner wall of AAA through ligand-receptor binding, using fluid-structure interaction (FSI) simulation by using a patient CT-scan images of the vascular system. The effect of blood flow through AAA on MBs delivery to the intended surface was also addressed. For this purpose, the adherence of four types of MBs with three different diameters to the inner surface wall of AAA was studied in a patient with 40-mm diameter aneurysm. The effects of the blood mechanical properties on the hematocrit (Hct) percentage of patients suffering from anemia and diabetes were studied. Moreover, the impact of variations in the artery inlet velocity on blood flow was addressed. Simulation results demonstrated the dependency of the surface density of MBs (SDM) adhered on the AAA lumen to the size and the type of MBs. It was observed that the amount of SDM due to adhesion on the AAA lumen for one of the commercially-approved MBs (Optison) with a diameter of 4.5 μm was higher than the other MBs. Furthermore, we have shown that the targeted drug delivery to the AAA lumen is more favorable in healthy individuals (45% Hct) compared to the patients with diabetes and anemia. Also, it was found that the targeted drug delivery method using MBs on the patients having AAA with complicated aneurysm shape and negative inlet blood flow velocity can be severely affected.
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Affiliation(s)
- Amir Shamloo
- School of Mechanical Engineering, Sharif University of Technology, Tehran, Iran.
| | - Sina Ebrahimi
- School of Mechanical Engineering, Sharif University of Technology, Tehran, Iran
| | - Ali Amani
- School of Mechanical Engineering, Sharif University of Technology, Tehran, Iran
| | - Famida Fallah
- School of Mechanical Engineering, Sharif University of Technology, Tehran, Iran
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14
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On the optimal choice of a hyperelastic model of ruptured and unruptured cerebral aneurysm. Sci Rep 2019; 9:15865. [PMID: 31676797 PMCID: PMC6825163 DOI: 10.1038/s41598-019-52229-y] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2019] [Accepted: 10/03/2019] [Indexed: 12/15/2022] Open
Abstract
In the last decade, preoperative modelling of the treatment of cerebral aneurysms is being actively developed. Fluid-structure interaction problem is a key point of a such modelling. Hence arises the question about the reasonable choice of the model of the vessel and aneurysm wall material to build the adequate model from the physical point of view. This study covers experimental investigation of 8 tissue samples of cerebral aneurysms and 1 tissue sample of a healthy cerebral artery. Results on statistical significance in ultimate stress for the classification of 2 cohorts of aneurysms: ruptured and unruptured described earlier in the literature were confirmed (p ≤ 0.01). We used the four most common models of hyperelastic material: Yeoh, Neo-Hookean and Mooney-Rivlin (3 and 5 parameter) models to describe the experimental data. In this study for the first time, we obtained a classification of hyperelastic models of cerebral aneurysm tissue, which allows to choose the most appropriate model for the simulation problems requirements depending on the physical interpretation of the considered problem: aneurysm status and range of deformation.
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15
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Salman HE, Ramazanli B, Yavuz MM, Yalcin HC. Biomechanical Investigation of Disturbed Hemodynamics-Induced Tissue Degeneration in Abdominal Aortic Aneurysms Using Computational and Experimental Techniques. Front Bioeng Biotechnol 2019; 7:111. [PMID: 31214581 PMCID: PMC6555197 DOI: 10.3389/fbioe.2019.00111] [Citation(s) in RCA: 42] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2019] [Accepted: 05/02/2019] [Indexed: 11/13/2022] Open
Abstract
Abdominal aortic aneurysm (AAA) is the dilatation of the aorta beyond 50% of the normal vessel diameter. It is reported that 4-8% of men and 0.5-1% of women above 50 years of age bear an AAA and it accounts for ~15,000 deaths per year in the United States alone. If left untreated, AAA might gradually expand until rupture; the most catastrophic complication of the aneurysmal disease that is accompanied by a striking overall mortality of 80%. The precise mechanisms leading to AAA rupture remains unclear. Therefore, characterization of disturbed hemodynamics within AAAs will help to understand the mechanobiological development of the condition which will contribute to novel therapies for the condition. Due to geometrical complexities, it is challenging to directly quantify disturbed flows for AAAs clinically. Two other approaches for this investigation are computational modeling and experimental flow measurement. In computational modeling, the problem is first defined mathematically, and the solution is approximated with numerical techniques to get characteristics of flow. In experimental flow measurement, once the setup providing physiological flow pattern in a phantom geometry is constructed, velocity measurement system such as particle image velocimetry (PIV) enables characterization of the flow. We witness increasing number of applications of these complimentary approaches for AAA investigations in recent years. In this paper, we outline the details of computational modeling procedures and experimental settings and summarize important findings from recent studies, which will help researchers for AAA investigations and rupture mechanics.
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Affiliation(s)
| | - Burcu Ramazanli
- Department of Mechanical Engineering, Middle East Technical University, Ankara, Turkey
| | - Mehmet Metin Yavuz
- Department of Mechanical Engineering, Middle East Technical University, Ankara, Turkey
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16
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Legerer C, Almsherqi ZA, McLachlan CS. Over-Wrapping of the Aortic Wall with an Elastic Extra-Aortic Wrap Results in Luminal Creasing. J Cardiovasc Dev Dis 2018; 5:jcdd5030042. [PMID: 30103504 PMCID: PMC6162522 DOI: 10.3390/jcdd5030042] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2018] [Revised: 08/08/2018] [Accepted: 08/08/2018] [Indexed: 12/18/2022] Open
Abstract
Elastic extra-aortic wrapping is a potential non-pharmacological way to improve aortic compliance and treat isolated systolic hypertension associated with a stiffened aorta. We aimed to use computer simulations to re-evaluate whether there is aortic shape distortion in aortic wrapping to achieve greater elasticity of the wrapped aortic segment. Non-linear transient numerical analysis based on an idealized hyper-elastic single-layered aorta model was performed to simulate the force/displacement regimes of external aortic wrapping. Pressure-displacement relationships were used to establish model aortic wall distensibilities of 4.3 and 5.5 (10−3 mmHg−1). A physiological pulsatile lumen pressure was employed to estimate the potential improvements in aortic distensibility by compression forces representing elastic aortic wrapping. In the less distensible model of the aortic wall there was increased systolic expansion in the wrapped segment. We found a risk of creasing of the aortic luminal wall with wrapping. Sufficient unloading of a thick and elastic aortic wall to induce increased compliance, as observed in elastic wrapping, is associated with the potential risk of over compression and folding (creasing) inside the lumen.
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Affiliation(s)
- Christian Legerer
- Rural Clinical School, Faculty of Medicine, University of New South Wales, Sydney, NSW 2052, Australia.
| | - Zakaria A Almsherqi
- Rural Clinical School, Faculty of Medicine, University of New South Wales, Sydney, NSW 2052, Australia.
- Yong Loo Lin School of Medicine, National University of Singapore, Singapore 119228, Singapore.
| | - Craig S McLachlan
- Rural Clinical School, Faculty of Medicine, University of New South Wales, Sydney, NSW 2052, Australia.
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17
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Dolgov VY, Klyshnikov KY, Ovcharenko EA, Glushkova TV, Batranin AV, Agienko AS, Kudryavtseva YA, Yuzhalin AE, Kutikhin AG. Finite Element Analysis-Based Approach for Prediction of Aneurysm-Prone Arterial Segments. J Med Biol Eng 2018. [DOI: 10.1007/s40846-018-0422-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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18
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Zhao L, Jin H, Yang B, Zhang S, Han S, Yin F, Feng Y. Correlation Between ABCA1 Gene Polymorphism and aopA-I and HDL-C in Abdominal Aortic Aneurysm. Med Sci Monit 2016; 22:172-6. [PMID: 26774504 PMCID: PMC4723058 DOI: 10.12659/msm.895298] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
BACKGROUND As the most common type of aneurysm, abdominal aortic aneurysm (AAA) has an unfavorable prognosis due to the high frequency of rupture. Studies have indicated a close relationship between the pathogenesis and progression of AAA and abnormal serum lipid levels. ATP-binding cassette transport protein A1 (ABCA1) is a cell-surface protein facilitating cellular efflux of cholesterol. The single-nucleotide polymorphism (SNP) of ABCA1 gene has been suggested to be correlated with abnormal metabolism of lipids. Therefore, this study aimed to investigate the relationship between ABCA1 polymorphism and apoA-I and HDL-C in an attempt to elucidate its correlation with AAA occurrence. MATERIAL/METHODS We included 126 AAA patients and 119 healthy controls in this study. PCR and restriction fragment length polymorphism (RFLP) were used to detect the SNP pattern of ABCA1 gene at locus rs2230806 from both AAA patients and healthy controls. The distribution pattern and correlation with apoA-I and HDL-C was analyzed. RESULTS The distribution of KK/RR genotype of ABCA1 gene had significant difference between disease and control group, with lower rates of RR genotype and R allele in the disease group (p<0.05). Levels of apoA-I and HDL-C, but not triglyceride and LDL-C levels, in AAA patients who carried R allele in ABCA1 gene (including RR and RK genotypes) were higher than in non-carriers (p<0.05). The R allele of ABCA1 gene was shown to be related with the occurrence of AAA (p<0.05). CONCLUSIONS Polymorphism of ABCA1 gene is correlated with AAA occurrence, possibly via the regulation of serum lipid metabolism by R allele.
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Affiliation(s)
- Lingfeng Zhao
- Department of Vascular Surgery, First Affiliated Hospital of Kunming Medical University, Kunming, Yunnan, China (mainland)
| | - Hui Jin
- Department of Vascular Surgery, First Affiliated Hospital of Kunming Medical University, Kunming, Yunnan, China (mainland)
| | - Bin Yang
- Department of Vascular Surgery, First Affiliated Hospital of Kunming Medical University, Kunming, Yunnan, China (mainland)
| | - Shichao Zhang
- Department of Vascular Surgery, First Affiliated Hospital of Kunming Medical University, Kunming, Yunnan, China (mainland)
| | - Shengbin Han
- Department of Vascular Surgery, First Affiliated Hospital of Kunming Medical University, Kunming, Yunnan, China (mainland)
| | - Fang Yin
- Department of Vascular Surgery, First Affiliated Hospital of Kunming Medical University, Kunming, Yunnan, China (mainland)
| | - Yaoyu Feng
- Department of Vascular Surgery, First Affiliated Hospital of Kunming Medical University, Kunming, Yunnan, China (mainland)
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A Review of Computational Methods to Predict the Risk of Rupture of Abdominal Aortic Aneurysms. BIOMED RESEARCH INTERNATIONAL 2015; 2015:861627. [PMID: 26509168 PMCID: PMC4609803 DOI: 10.1155/2015/861627] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/20/2015] [Accepted: 05/26/2015] [Indexed: 12/02/2022]
Abstract
Computational methods have played an important role in health care in recent years, as determining parameters that affect a certain medical condition is not possible in experimental conditions in many cases. Computational fluid dynamics (CFD) methods have been used to accurately determine the nature of blood flow in the cardiovascular and nervous systems and air flow in the respiratory system, thereby giving the surgeon a diagnostic tool to plan treatment accordingly. Machine learning or data mining (MLD) methods are currently used to develop models that learn from retrospective data to make a prediction regarding factors affecting the progression of a disease. These models have also been successful in incorporating factors such as patient history and occupation. MLD models can be used as a predictive tool to determine rupture potential in patients with abdominal aortic aneurysms (AAA) along with CFD-based prediction of parameters like wall shear stress and pressure distributions. A combination of these computer methods can be pivotal in bridging the gap between translational and outcomes research in medicine. This paper reviews the use of computational methods in the diagnosis and treatment of AAA.
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20
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Raut SS, Liu P, Finol EA. An approach for patient-specific multi-domain vascular mesh generation featuring spatially varying wall thickness modeling. J Biomech 2015; 48:1972-81. [PMID: 25976018 DOI: 10.1016/j.jbiomech.2015.04.006] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2014] [Revised: 04/02/2015] [Accepted: 04/02/2015] [Indexed: 11/24/2022]
Abstract
In this work, we present a computationally efficient image-derived volume mesh generation approach for vasculatures that implements spatially varying patient-specific wall thickness with a novel inward extrusion of the wall surface mesh. Multi-domain vascular meshes with arbitrary numbers, locations, and patterns of both iliac bifurcations and thrombi can be obtained without the need to specify features or landmark points as input. In addition, the mesh output is coordinate-frame independent and independent of the image grid resolution with high dimensional accuracy and mesh quality, devoid of errors typically found in off-the-shelf image-based model generation workflows. The absence of deformable template models or Cartesian grid-based methods enables the present approach to be sufficiently robust to handle aneurysmatic geometries with highly irregular shapes, arterial branches nearly parallel to the image plane, and variable wall thickness. The assessment of the methodology was based on i) estimation of the surface reconstruction accuracy, ii) validation of the output mesh using an aneurysm phantom, and iii) benchmarking the volume mesh quality against other frameworks. For the phantom image dataset (pixel size 0.105 mm; slice spacing 0.7 mm; and mean wall thickness 1.401±0.120 mm), the average wall thickness in the mesh was 1.459±0.123 mm. The absolute error in average wall thickness was 0.060±0.036 mm, or about 8.6% of the largest image grid spacing (0.7 mm) and 4.36% of the actual mean wall thickness. Mesh quality metrics and the ability to reproduce regional variations of wall thickness were found superior to similar alternative frameworks.
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Affiliation(s)
- Samarth S Raut
- Carnegie Mellon University, Pittsburgh, PA 15213, United States.
| | - Peng Liu
- Carnegie Mellon University, Pittsburgh, PA 15213, United States.
| | - Ender A Finol
- University of Texas at San Antonio, Department of Biomedical Engineering, AET 1.360, One UTSA Circle, San Antonio, TX 78249, United States.
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