1
|
Wei H, Wang G, Tian Q, Liu C, Han W, Wang J, He P, Li M. Low shear stress induces macrophage infiltration and aggravates aneurysm wall inflammation via CCL7/CCR1/TAK1/ NF-κB axis. Cell Signal 2024; 117:111122. [PMID: 38417634 DOI: 10.1016/j.cellsig.2024.111122] [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: 11/20/2023] [Revised: 02/18/2024] [Accepted: 02/25/2024] [Indexed: 03/01/2024]
Abstract
BACKGROUND This study aimed to elucidate the mechanism by which wall shear stress (WSS) influences vascular walls, accounting for the susceptibility of intracranial aneurysms (IAs) to rupture. METHOD We collected blood samples from the sacs of 24 ruptured and 28 unruptured IAs and analyzed the expression of chemokine CCL7 using enzyme-linked immunosorbent assay (ELISA). Univariate and multivariate logistic regression analyses were employed to assess clinical data, aneurysm morphology, and hemodynamics in both groups. Pearson correlation analysis investigated the relationship between CCL7 expression in aneurysm sac blood and WSS. Additionally, we established a bionic cell parallel plate co-culture shear stress model and a mouse low shear stress (LSS) model. The model was modulated using CCL7 recombinant protein, CCR1 inhibitor, and TAK1 inhibitor. We further evaluated CCL7 expression in endothelial cells and the levels of TAK1, NF-κB, IL-1β, and TNF-α in macrophages. Subsequently, the intergroup differences in expression were calculated. RESULTS CCL7 expression was significantly higher in the ruptured group compared to the unruptured group. Hemodynamic analysis indicated that WSS was an independent predictor of the risk of aneurysm rupture. A negative linear correlation was observed between CCL7 expression and WSS. Upon addition of CCL7 recombinant protein, upregulation of CCR1 expression and increased levels of p-TAK1 and p-p65 were observed. Treatment with CCR1 and TAK1 inhibitors reduced inflammatory cytokine expression in macrophages under LSS conditions. Overexpression of TAK1 significantly alleviated the inhibitory effects of CCR1 inhibitors on p-p65 and inflammatory cytokines. CONCLUSION LSS prompts endothelial cells to secrete CCL7, which, upon binding to the macrophage surface receptor CCR1, stimulates the release of macrophage inflammatory factors via the TAK1/NF-κB signaling pathway. This process exacerbates aneurysm wall inflammation and increases the risk of aneurysm rupture.
Collapse
Affiliation(s)
- Heng Wei
- Department of Neurosurgery, Renmin Hospital of Wuhan University, Wuhan 430060, Hubei Province, China
| | - Guijun Wang
- Department of Neurosurgery, Renmin Hospital of Wuhan University, Wuhan 430060, Hubei Province, China
| | - Qi Tian
- Department of Neurosurgery, Renmin Hospital of Wuhan University, Wuhan 430060, Hubei Province, China
| | - Chengli Liu
- Department of Neurosurgery, Renmin Hospital of Wuhan University, Wuhan 430060, Hubei Province, China
| | - Wenrui Han
- Department of Neurosurgery, Renmin Hospital of Wuhan University, Wuhan 430060, Hubei Province, China
| | - Jianfeng Wang
- Department of Neurosurgery, Renmin Hospital of Wuhan University, Wuhan 430060, Hubei Province, China
| | - Peibang He
- Department of Neurosurgery, Renmin Hospital of Wuhan University, Wuhan 430060, Hubei Province, China
| | - Mingchang Li
- Department of Neurosurgery, Renmin Hospital of Wuhan University, Wuhan 430060, Hubei Province, China.
| |
Collapse
|
2
|
Liu Y, Chen S, Zhang E, Xu Y, Deng X, Hu Z, Nie S, Lin Y, Huang Y. Exploring the potential of VGLL3 methylation as a prognostic indicator for intracranial aneurysm with gender-specific considerations. Biosci Rep 2024; 44:BSR20231374. [PMID: 38348744 PMCID: PMC10912501 DOI: 10.1042/bsr20231374] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2023] [Revised: 01/24/2024] [Accepted: 02/09/2024] [Indexed: 03/02/2024] Open
Abstract
DNA methylation is widely recognized to play a role in intracranial aneurysm (IA) pathogenesis. We investigated the levels of methylation of vestigial-like 3 (VGLL3) in IA and explored its potential as a prognostic indicator. A total of 48 patients with IA and 48 healthy controls were included in the present study. Methylation levels of CpG sites were assessed using bisulfite pyrosequencing, and levels of VGLL3, TEAD, and YAP in the blood were measured by real-time quantitative polymerase chain reaction testing. VGLL3 methylation was significantly higher in controls than in IA patients (P=0.001), and this phenomenon was more pronounced in females (P<0.001). Compared with the control group, the expression levels of VGLL3 and TEAD in the blood of IA patients were significantly increased, while YAP was significantly decreased. VGLL3 methylation was positively correlated with HDL (P=0.003) and female Lpa concentration (r = 0.426, P=0.03), and was also negatively correlated with age (P=0.003), APOE (P=0.005), and VGLL3 mRNA expression (P<0.001). Methylation and mRNA expression of VGLL3 may serve as indicators of IA risk in females (AUC = 0.810 and 0.809). VGLL3 methylation may participate in the pathogenesis of IA by regulating the expression of the VGLL3/TEAD/YAP pathway, and its gene methylation and expression levels have IA risk prediction value.
Collapse
Affiliation(s)
- Yuchun Liu
- Department of Neurosurgery, The First Affiliated Hospital of Ningbo University, Ningbo, Zhejiang 315010, China
- Laboratory of Neurological Diseases and Brain Function, The First Affiliated Hospital of Ningbo University, Ningbo, Zhejiang 315010, China
| | - Siqi Chen
- Department of Neurosurgery, The First Affiliated Hospital of Ningbo University, Ningbo, Zhejiang 315010, China
- Laboratory of Neurological Diseases and Brain Function, The First Affiliated Hospital of Ningbo University, Ningbo, Zhejiang 315010, China
- Key Laboratory of Precision Medicine for Atherosclerotic Diseases of Zhejiang Province, Ningbo, Zhejiang 315010, China
| | - Enhao Zhang
- Department of Neurosurgery, The First Affiliated Hospital of Ningbo University, Ningbo, Zhejiang 315010, China
- Laboratory of Neurological Diseases and Brain Function, The First Affiliated Hospital of Ningbo University, Ningbo, Zhejiang 315010, China
- Key Laboratory of Precision Medicine for Atherosclerotic Diseases of Zhejiang Province, Ningbo, Zhejiang 315010, China
| | - Yinbin Xu
- Department of Neurosurgery, The First Affiliated Hospital of Ningbo University, Ningbo, Zhejiang 315010, China
- Laboratory of Neurological Diseases and Brain Function, The First Affiliated Hospital of Ningbo University, Ningbo, Zhejiang 315010, China
- Key Laboratory of Precision Medicine for Atherosclerotic Diseases of Zhejiang Province, Ningbo, Zhejiang 315010, China
| | - Xinpeng Deng
- Department of Neurosurgery, The First Affiliated Hospital of Ningbo University, Ningbo, Zhejiang 315010, China
- Laboratory of Neurological Diseases and Brain Function, The First Affiliated Hospital of Ningbo University, Ningbo, Zhejiang 315010, China
- Key Laboratory of Precision Medicine for Atherosclerotic Diseases of Zhejiang Province, Ningbo, Zhejiang 315010, China
| | - Ziliang Hu
- Department of Neurosurgery, The First Affiliated Hospital of Ningbo University, Ningbo, Zhejiang 315010, China
- Laboratory of Neurological Diseases and Brain Function, The First Affiliated Hospital of Ningbo University, Ningbo, Zhejiang 315010, China
- Key Laboratory of Precision Medicine for Atherosclerotic Diseases of Zhejiang Province, Ningbo, Zhejiang 315010, China
| | - Sheng Nie
- Department of Neurosurgery, The First Affiliated Hospital of Ningbo University, Ningbo, Zhejiang 315010, China
- Laboratory of Neurological Diseases and Brain Function, The First Affiliated Hospital of Ningbo University, Ningbo, Zhejiang 315010, China
| | - Yinglu Lin
- Department of Neurology, The Second People’s Hospital of Pingyang County, Wenzhou, Zhejiang 325400, China
| | - Yi Huang
- Department of Neurosurgery, The First Affiliated Hospital of Ningbo University, Ningbo, Zhejiang 315010, China
- Laboratory of Neurological Diseases and Brain Function, The First Affiliated Hospital of Ningbo University, Ningbo, Zhejiang 315010, China
- Key Laboratory of Precision Medicine for Atherosclerotic Diseases of Zhejiang Province, Ningbo, Zhejiang 315010, China
| |
Collapse
|
3
|
Joerger AK, Albrecht C, Rothhammer V, Neuhaus K, Wagner A, Meyer B, Wostrack M. The Role of Gut and Oral Microbiota in the Formation and Rupture of Intracranial Aneurysms: A Literature Review. Int J Mol Sci 2023; 25:48. [PMID: 38203219 PMCID: PMC10779325 DOI: 10.3390/ijms25010048] [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: 11/12/2023] [Revised: 12/14/2023] [Accepted: 12/18/2023] [Indexed: 01/12/2024] Open
Abstract
In recent years, there has been a growing interest in the role of the microbiome in cardiovascular and cerebrovascular diseases. Emerging research highlights the potential role of the microbiome in intracranial aneurysm (IA) formation and rupture, particularly in relation to inflammation. In this review, we aim to explore the existing literature regarding the influence of the gut and oral microbiome on IA formation and rupture. In the first section, we provide background information, elucidating the connection between inflammation and aneurysm formation and presenting potential mechanisms of gut-brain interaction. Additionally, we explain the methods for microbiome analysis. The second section reviews existing studies that investigate the relationship between the gut and oral microbiome and IAs. We conclude with a prospective overview, highlighting the extent to which the microbiome is already therapeutically utilized in other fields. Furthermore, we address the challenges associated with the context of IAs that still need to be overcome.
Collapse
Affiliation(s)
- Ann-Kathrin Joerger
- Department of Neurosurgery, Klinikum Rechts der Isar, Technical University, 81675 Munich, Germany; (A.-K.J.); (B.M.)
| | - Carolin Albrecht
- Department of Neurosurgery, Klinikum Rechts der Isar, Technical University, 81675 Munich, Germany; (A.-K.J.); (B.M.)
| | - Veit Rothhammer
- Department of Neurology, University Hospital Erlangen, Friedrich-Alexander University Erlangen Nuremberg, 91054 Erlangen, Germany;
| | - Klaus Neuhaus
- Core Facility Microbiom, ZIEL Institute for Food & Health, Technical University of Munich, 85354 Freising, Germany;
| | - Arthur Wagner
- Department of Neurosurgery, Klinikum Rechts der Isar, Technical University, 81675 Munich, Germany; (A.-K.J.); (B.M.)
| | - Bernhard Meyer
- Department of Neurosurgery, Klinikum Rechts der Isar, Technical University, 81675 Munich, Germany; (A.-K.J.); (B.M.)
| | - Maria Wostrack
- Department of Neurosurgery, Klinikum Rechts der Isar, Technical University, 81675 Munich, Germany; (A.-K.J.); (B.M.)
| |
Collapse
|
4
|
Zaniker EJ, Babayev E, Duncan FE. Common mechanisms of physiological and pathological rupture events in biology: novel insights into mammalian ovulation and beyond. Biol Rev Camb Philos Soc 2023; 98:1648-1667. [PMID: 37157877 PMCID: PMC10524764 DOI: 10.1111/brv.12970] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2022] [Revised: 04/17/2023] [Accepted: 04/24/2023] [Indexed: 05/10/2023]
Abstract
Ovulation is a cyclical biological rupture event fundamental to fertilisation and endocrine function. During this process, the somatic support cells that surround the germ cell undergo a remodelling process that culminates in breakdown of the follicle wall and release of a mature egg. Ovulation is driven by known proteolytic and inflammatory pathways as well as structural alterations to the follicle vasculature and the fluid-filled antral cavity. Ovulation is one of several types of systematic remodelling that occur in the human body that can be described as rupture. Although ovulation is a physiological form of rupture, other types of rupture occur in the human body which can be pathological, physiological, or both. In this review, we use intracranial aneurysms and chorioamniotic membrane rupture as examples of rupture events that are pathological or both pathological and physiological, respectively, and compare these to the rupture process central to ovulation. Specifically, we compared existing transcriptomic profiles, immune cell functions, vascular modifications, and biomechanical forces to identify common processes that are conserved between rupture events. In our transcriptomic analysis, we found 12 differentially expressed genes in common among two different ovulation data sets and one intracranial aneurysm data set. We also found three genes that were differentially expressed in common for both ovulation data sets and one chorioamniotic membrane rupture data set. Combining analysis of all three data sets identified two genes (Angptl4 and Pfkfb4) that were upregulated across rupture systems. Some of the identified genes, such as Rgs2, Adam8, and Lox, have been characterised in multiple rupture contexts, including ovulation. Others, such as Glul, Baz1a, and Ddx3x, have not yet been characterised in the context of ovulation and warrant further investigation as potential novel regulators. We also identified overlapping functions of mast cells, macrophages, and T cells in the process of rupture. Each of these rupture systems share local vasoconstriction around the rupture site, smooth muscle contractions away from the site of rupture, and fluid shear forces that initially increase and then decrease to predispose one specific region to rupture. Experimental techniques developed to study these structural and biomechanical changes that underlie rupture, such as patient-derived microfluidic models and spatiotemporal transcriptomic analyses, have not yet been comprehensively translated to the study of ovulation. Review of the existing knowledge, transcriptomic data, and experimental techniques from studies of rupture in other biological systems yields a better understanding of the physiology of ovulation and identifies avenues for novel studies of ovulation with techniques and targets from the study of vascular biology and parturition.
Collapse
Affiliation(s)
- Emily J. Zaniker
- Department of Obstetrics and Gynecology, Feinberg School of Medicine, Northwestern University, 303 E. Superior Street, Lurie 10-109, Chicago, IL 60611, USA
| | - Elnur Babayev
- Department of Obstetrics and Gynecology, Feinberg School of Medicine, Northwestern University, 303 E. Superior Street, Lurie 10-109, Chicago, IL 60611, USA
| | - Francesca E. Duncan
- Department of Obstetrics and Gynecology, Feinberg School of Medicine, Northwestern University, 303 E. Superior Street, Lurie 10-109, Chicago, IL 60611, USA
| |
Collapse
|
5
|
Cayron AF, Morel S, Allémann E, Bijlenga P, Kwak BR. Imaging of intracranial aneurysms in animals: a systematic review of modalities. Neurosurg Rev 2023; 46:56. [PMID: 36786880 PMCID: PMC9928939 DOI: 10.1007/s10143-023-01953-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2022] [Revised: 11/28/2022] [Accepted: 01/23/2023] [Indexed: 02/15/2023]
Abstract
Intracranial aneurysm (IA) animal models are paramount to study IA pathophysiology and to test new endovascular treatments. A number of in vivo imaging modalities are available to characterize IAs at different stages of development in these animal models. This review describes existing in vivo imaging techniques used so far to visualize IAs in animal models. We systematically searched for studies containing in vivo imaging of induced IAs in animal models in PubMed and SPIE Digital library databases between 1 January 1945 and 13 July 2022. A total of 170 studies were retrieved and reviewed in detail, and information on the IA animal model, the objective of the study, and the imaging modality used was collected. A variety of methods to surgically construct or endogenously induce IAs in animals were identified, and 88% of the reviewed studies used surgical methods. The large majority of IA imaging in animals was performed for 4 reasons: basic research for IA models, testing of new IA treatment modalities, research on IA in vivo imaging of IAs, and research on IA pathophysiology. Six different imaging techniques were identified: conventional catheter angiography, computed tomography angiography, magnetic resonance angiography, hemodynamic imaging, optical coherence tomography, and fluorescence imaging. This review presents and discusses the advantages and disadvantages of all in vivo IA imaging techniques used in animal models to help future IA studies finding the most appropriate IA imaging modality and animal model to answer their research question.
Collapse
Affiliation(s)
- Anne F Cayron
- Department of Pathology and Immunology, Faculty of Medicine, University of Geneva, Rue Michel-Servet 1, CH-1211, Geneva, Switzerland
- Geneva Center for Inflammation Research, Faculty of Medicine, University of Geneva, Geneva, Switzerland
- School of Pharmaceutical Sciences, University of Geneva, Geneva, Switzerland
- Institute of Pharmaceutical Sciences of Western Switzerland, University of Geneva, Geneva, Switzerland
| | - Sandrine Morel
- Department of Pathology and Immunology, Faculty of Medicine, University of Geneva, Rue Michel-Servet 1, CH-1211, Geneva, Switzerland
- Geneva Center for Inflammation Research, Faculty of Medicine, University of Geneva, Geneva, Switzerland
- Department of Clinical Neurosciences - Division of Neurosurgery, Geneva University Hospitals and Faculty of Medicine, University of Geneva, Geneva, Switzerland
| | - Eric Allémann
- School of Pharmaceutical Sciences, University of Geneva, Geneva, Switzerland
- Institute of Pharmaceutical Sciences of Western Switzerland, University of Geneva, Geneva, Switzerland
| | - Philippe Bijlenga
- Department of Clinical Neurosciences - Division of Neurosurgery, Geneva University Hospitals and Faculty of Medicine, University of Geneva, Geneva, Switzerland
| | - Brenda R Kwak
- Department of Pathology and Immunology, Faculty of Medicine, University of Geneva, Rue Michel-Servet 1, CH-1211, Geneva, Switzerland.
- Geneva Center for Inflammation Research, Faculty of Medicine, University of Geneva, Geneva, Switzerland.
| |
Collapse
|
6
|
Murakami M, Jiang F, Kageyama N, Chen X. Computational Fluid Dynamics Analysis of Blood Flow Changes during the Growth of Saccular Abdominal Aortic Aneurysm. Ann Vasc Dis 2022; 15:260-267. [PMID: 36644268 PMCID: PMC9816029 DOI: 10.3400/avd.oa.22-00098] [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: 09/02/2022] [Accepted: 09/24/2022] [Indexed: 11/06/2022] Open
Abstract
Computational fluid dynamics analysis of the growth process of saccular abdominal aortic aneurysm was performed. A 3D model of aortic aneurysm was created based on CT images. Properties in terms of wall shear stress, mean flow velocity, mean pressure, energy loss, and pressure loss coefficient were calculated using thermal fluid analysis software "ANSYS CFX." As the aneurysm expanded, the mean flow velocity decreased and the wall shear stress, mean pressure, energy loss, and pressure loss coefficient increased. Wall shear stress increased when the aneurysm was small, suggesting that is related to the development and growth of the aneurysm. (This is secondary publication from J Jpn Coll Angiol 2021; 61: 3-10.).
Collapse
Affiliation(s)
- Masanori Murakami
- Department of Cardiovascular Surgery, National Hospital Organization, Kanmon Medical Center, Shimonoseki, Yamaguchi, Japan,Corresponding author: Masanori Murakami, MD, PhD. Department of Cardiovascular Surgery, National Hospital Organization, Kanmon Medical Center, 1-1 Choufusotoura-chou, Shimonoseki, Yamaguchi 752-8510, Japan Tel: +81-83-241-1199, Fax: +81-83-241-1301, E-mail:
| | - Fei Jiang
- Department of Mechanical Engineering, Graduate School of Sciences and Technology for Innovation, Yamaguchi University, Yamaguchi, Yamaguchi, Japan
| | - Nobuyasu Kageyama
- Department of Mechanical Engineering, Graduate School of Sciences and Technology for Innovation, Yamaguchi University, Yamaguchi, Yamaguchi, Japan
| | - Xian Chen
- Department of Mechanical Engineering, Graduate School of Sciences and Technology for Innovation, Yamaguchi University, Yamaguchi, Yamaguchi, Japan
| |
Collapse
|
7
|
Long-Lasting Unruptured Large Intracranial Aneurysm in Bilateral Moyamoya Disease: Case Report. Case Rep Neurol Med 2022; 2022:2635724. [PMID: 36246053 PMCID: PMC9553707 DOI: 10.1155/2022/2635724] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2022] [Accepted: 09/07/2022] [Indexed: 11/17/2022] Open
Abstract
Introduction. The rupture risk of intracranial aneurysms in patients with moyamoya disease is higher than that in the general population. We report a confirmed case of moyamoya disease with bilateral middle cerebral artery (MCA) occlusion with a large and long-lasting aneurysm. Case. A 71-year-old woman visited the clinic with a large intracranial aneurysm. The patient was diagnosed with an ischemic stroke 2 months ago. She exhibited weakness in the left upper and lower extremities and dysarthria and was taking aspirin. The brain magnetic resonance imaging showed complete occlusion in the bilateral MCA proximal (M1) and a large 11 × 11 mm nonruptured cerebral aneurysm in the A3 segment of the left anterior cerebral artery. On transfemoral cerebral angiography, the patient was diagnosed with Suzuki grade VI moyamoya disease with bilateral MCA occlusion. After 7 years, the cerebral aneurysm size further increased, but it remained unruptured. Conclusions. Here, the patient had moyamoya disease with a large aneurysm, but aneurysmal rupture did not occur even after 7 years. Our case report might help in understanding the mechanisms of cerebral aneurysm occurrence and rupture in moyamoya patients.
Collapse
|
8
|
Xu J, Karmonik C, Yu Y, Lv N, Shi Z, Liu JM, Huang Q. Modeling Flow Diverters using a Porous Medium Approach: A Fast Alternative to Virtual Flow Diverter Deployment. World Neurosurg 2022; 164:e501-e508. [PMID: 35552028 DOI: 10.1016/j.wneu.2022.04.132] [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: 02/28/2022] [Revised: 04/29/2022] [Accepted: 04/29/2022] [Indexed: 11/29/2022]
Abstract
BACKGROUND The Tubridge flow diverter (FD) is a novel device aimed at reconstructing the parent artery and eliminating the aneurysm. Numerical simulations based on virtual FD deployment allow the assessment of the complex nature of aneurismal flow changes before the actual intervention but are demanding on computational resources. Here, we evaluate an alternative strategy of modeling FD effects for the Tubridge system using a porous medium. The goal of this study is to reduce demands on time and complexity of the simulation procedure for applications in clinical research. METHODS Ten patient-specific aneurysm models were reconstructed from retrospectively collected diagnostic 3D-DSA images. Virtual FDs were deployed (SolidWorks, Meshmixer) and corresponding porous medium patches were constructed at the ostium with a research CFD prototype (Siemens Healthineers, Forchheim, Germany). Hemodynamic conditions were simulated in two approaches. RESULTS Hemodynamics inside the aneurysm based on these two approaches were compared. Both approaches yielded similar results. Mean wall shear stress (WSS) and mean pressure of the aneurysmal wall correlated significantly (r=0.8, r=1.0, p-value<0.05) as did mean velocity, mean pressure at a region inside the aneurysm, at the ostium and at a cross section containing the main vertex (for velocities r=0.9; for pressures r=1.0, p-value<0.05). The use of porous medium patches reduced the preparation and simulation time together by approximately 50%. CONCLUSION Using a porous medium approach yields comparable mean values for hemodynamic alterations compared to direct virtual FD simulations. Additionally, the porous medium approach greatly reduced the modeling complexity and computation time.
Collapse
Affiliation(s)
- Jinyu Xu
- From the Department of Neurosurgery, Changhai Hospital, Second Military Medical University, Shanghai, China
| | - Christof Karmonik
- Translational Imaging Center, MRI core, Houston Methodist Research Institute, Houston TX, USA
| | - Ying Yu
- From the Department of Neurosurgery, Changhai Hospital, Second Military Medical University, Shanghai, China
| | - Nan Lv
- From the Department of Neurosurgery, Changhai Hospital, Second Military Medical University, Shanghai, China
| | - Zhaoyue Shi
- Translational Imaging Center, MRI core, Houston Methodist Research Institute, Houston TX, USA
| | - Jian-Min Liu
- From the Department of Neurosurgery, Changhai Hospital, Second Military Medical University, Shanghai, China.
| | - Qinghai Huang
- From the Department of Neurosurgery, Changhai Hospital, Second Military Medical University, Shanghai, China.
| |
Collapse
|
9
|
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.
Collapse
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
| |
Collapse
|
10
|
Tang H, Wang Q, Xu F, Zhang X, Zeng Z, Yan Y, Lu Z, Xue G, Zuo Q, Luo Y, Liu J, Huang Q. Underlying mechanism of hemodynamics and intracranial aneurysm. Chin Neurosurg J 2021; 7:44. [PMID: 34847937 PMCID: PMC8638472 DOI: 10.1186/s41016-021-00260-2] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2020] [Accepted: 09/17/2021] [Indexed: 12/13/2022] Open
Abstract
In modern society, subarachnoid hemorrhage, mostly caused by intracranial aneurysm rupture, is accompanied by high disability and mortality rate, which has become a major threat to human health. Till now, the etiology of intracranial aneurysm has not been entirely clarified. In recent years, more and more studies focus on the relationship between hemodynamics and intracranial aneurysm. Under the physiological condition, the mechanical force produced by the stable blood flow in the blood vessels keeps balance with the structure of the blood vessels. When the blood vessels are stimulated by the continuous abnormal blood flow, the functional structure of the blood vessels changes, which becomes the pathophysiological basis of the inflammation and atherosclerosis of the blood vessels and further promotes the occurrence and development of the intracranial aneurysm. This review will focus on the relationship between hemodynamics and intracranial aneurysms, will discuss the mechanism of occurrence and development of intracranial aneurysms, and will provide a new perspective for the research and treatment of intracranial aneurysms.
Collapse
Affiliation(s)
- Haishuang Tang
- Department of Neurosurgery, Changhai Hospital, Naval Military Medical University, 168 Changhai Road, Shanghai, 200433, People's Republic of China.,Naval Medical Center of PLA, Naval Military Medical University, Shanghai, 200050, People's Republic of China
| | - Qingsong Wang
- Department of Cardiology, the First Medical Centre, Chinese PLA General Hospital, Beijing, 100853, People's Republic of China
| | - Fengfeng Xu
- Naval Medical Center of PLA, Naval Military Medical University, Shanghai, 200050, People's Republic of China
| | - Xiaoxi Zhang
- Department of Neurosurgery, Changhai Hospital, Naval Military Medical University, 168 Changhai Road, Shanghai, 200433, People's Republic of China
| | - Zhangwei Zeng
- Department of Neurosurgery, Changhai Hospital, Naval Military Medical University, 168 Changhai Road, Shanghai, 200433, People's Republic of China
| | - Yazhou Yan
- Department of Neurosurgery, Changhai Hospital, Naval Military Medical University, 168 Changhai Road, Shanghai, 200433, People's Republic of China
| | - Zhiwen Lu
- Department of Neurosurgery, Changhai Hospital, Naval Military Medical University, 168 Changhai Road, Shanghai, 200433, People's Republic of China
| | - Gaici Xue
- Department of Neurosurgery, Changhai Hospital, Naval Military Medical University, 168 Changhai Road, Shanghai, 200433, People's Republic of China
| | - Qiao Zuo
- Department of Neurosurgery, Changhai Hospital, Naval Military Medical University, 168 Changhai Road, Shanghai, 200433, People's Republic of China
| | - Yin Luo
- Department of Neurosurgery, Changhai Hospital, Naval Military Medical University, 168 Changhai Road, Shanghai, 200433, People's Republic of China
| | - Jianmin Liu
- Department of Neurosurgery, Changhai Hospital, Naval Military Medical University, 168 Changhai Road, Shanghai, 200433, People's Republic of China.
| | - Qinghai Huang
- Department of Neurosurgery, Changhai Hospital, Naval Military Medical University, 168 Changhai Road, Shanghai, 200433, People's Republic of China.
| |
Collapse
|
11
|
Malek AM, Hippelheuser JE, Lauric A. Vortex formation and associated aneurysmogenic transverse rotational shear stress near the apex of wide-angle cerebral bifurcations. J Neurosurg 2021:1-12. [PMID: 34715656 DOI: 10.3171/2021.6.jns204385] [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: 12/20/2020] [Accepted: 06/15/2021] [Indexed: 11/06/2022]
Abstract
OBJECTIVE Aneurysm formation preferentially occurs at the site of wide-angle cerebral arterial bifurcations, which were recently shown to have a high longitudinal positive wall shear stress (WSS) gradient that promotes aneurysm formation. The authors sought to explore the other components of the hemodynamic environment that are altered with increasing bifurcation angle in the apical region and the effects of these components on WSS patterns on the vessel wall that may modulate aneurysm genesis and progression. METHODS Parametric models of symmetrical and asymmetrical bifurcations were created with increasing bifurcation angles (45°-240°), and 3D rotational angiography models of 13 middle cerebral artery (MCA) bifurcations (7 aneurysmal, 6 controls) were analyzed using computational fluid dynamics. For aneurysmal bifurcations, the aneurysm was digitally removed to uncover hemodynamics at the apex. WSS vectors along cross-sectional planes distal to the bifurcation apex were decomposed as orthogonal projections to the cut plane into longitudinal and transverse (tangential to the cross-sectional plane) components. Transverse rotational WSS (TRWSS) and TRWSS gradients (TRWSSGs) were sampled and evaluated at the apex and immediately distal from the apex. RESULTS In parametric models, increased bifurcation angle was associated with transverse flow vortex formation with emergence of an associated apical high TRWSS with highly aneurysmogenic positive TRWSSGs. While TRWSS decayed rapidly away from the apex in narrow-angle bifurcations, it remained greatly elevated for many radii downstream in aneurysm-prone wider bifurcations. In asymmetrical bifurcations, TRWSS was higher on the aneurysm-prone daughter vessel associated with the wider angle. Patient-derived models with aneurysmal bifurcations had wider angles (149.33° ± 12.56° vs 98.17° ± 8.67°, p < 0.001), with significantly higher maximum TRWSS (1.37 ± 0.67 vs 0.48 ± 0.23 Pa, p = 0.01) and TRWSSG (1.78 ± 0.92 vs 0.76 ± 0.50 Pa/mm, p = 0.03) compared to control nonaneurysmal bifurcations. CONCLUSIONS Wider vascular bifurcations are associated with a novel and to the authors' knowledge previously undescribed transverse component rotational wall shear stress associated with a positive (aneurysmogenic) spatial gradient. The resulting hemodynamic insult, demonstrated in both parametric models and patient-based anatomy, is noted to decay rapidly away from the protection of the medial pad in healthy narrow-angle bifurcations but remain elevated distally downstream of wide-angle aneurysm-prone bifurcations. This TRWSS serves as a new contribution to the hemodynamic environment favoring aneurysm formation and progression at wide cerebral bifurcations and may have clinical implications favoring interventions that reduce bifurcation angle.
Collapse
Affiliation(s)
- Adel M Malek
- 1Department of Neurosurgery, Tufts Medical Center and Tufts University School of Medicine, Boston, Massachusetts
| | - James E Hippelheuser
- 1Department of Neurosurgery, Tufts Medical Center and Tufts University School of Medicine, Boston, Massachusetts
| | - Alexandra Lauric
- 1Department of Neurosurgery, Tufts Medical Center and Tufts University School of Medicine, Boston, Massachusetts
| |
Collapse
|
12
|
Swiatek VM, Neyazi B, Roa JA, Zanaty M, Samaniego EA, Ishii D, Lu Y, Sandalcioglu IE, Saalfeld S, Berg P, Hasan DM. Aneurysm Wall Enhancement Is Associated With Decreased Intrasaccular IL-10 and Morphological Features of Instability. Neurosurgery 2021; 89:664-671. [PMID: 34245147 PMCID: PMC8578742 DOI: 10.1093/neuros/nyab249] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2020] [Accepted: 05/08/2021] [Indexed: 02/06/2023] Open
Abstract
BACKGROUND High-resolution vessel wall imaging plays an increasingly important role in assessing the risk of aneurysm rupture. OBJECTIVE To introduce an approach toward the validation of the wall enhancement as a direct surrogate parameter for aneurysm stability. METHODS A total of 19 patients harboring 22 incidental intracranial aneurysms were enrolled in this study. The aneurysms were dichotomized according to their aneurysm-to-pituitary stalk contrast ratio using a cutoff value of 0.5 (nonenhancing < 0.5; enhancing ≥ 0.5). We evaluated the association of aneurysm wall enhancement with morphological characteristics, hemodynamic features, and inflammatory chemokines directly measured inside the aneurysm. RESULTS Differences in plasma concentration of chemokines and inflammatory molecules, morphological, and hemodynamic parameters were analyzed using the Welch test or Mann-Whitney U test. The concentration ΔIL-10 in the lumen of intracranial aneurysms with low wall enhancement was significantly increased compared to aneurysms with strong aneurysm wall enhancement (P = .014). The analysis of morphological and hemodynamic parameters showed significantly increased values for aneurysm volume (P = .03), aneurysm area (P = .044), maximal diameter (P = .049), and nonsphericity index (P = .021) for intracranial aneurysms with strong aneurysm wall enhancement. None of the hemodynamic parameters reached statistical significance; however, the total viscous shear force computed over the region of low wall shear stress showed a strong tendency toward significance (P = .053). CONCLUSION Aneurysmal wall enhancement shows strong associations with decreased intrasaccular IL-10 and established morphological indicators of aneurysm instability.
Collapse
Affiliation(s)
- Vanessa M Swiatek
- Deparment of Neurosurgery, Otto-von-Guericke University, Magdeburg, Saxony Anhalt, Germany
| | - Belal Neyazi
- Deparment of Neurosurgery, Otto-von-Guericke University, Magdeburg, Saxony Anhalt, Germany
| | - Jorge A Roa
- Deparment of Neurosurgery, University of Iowa Hospitals and Clinics, Iowa City, Iowa, USA
- Deparment of Neurology, University of Iowa Hospitals and Clinics, Iowa City, Iowa, USA
| | - Mario Zanaty
- Deparment of Neurosurgery, University of Iowa Hospitals and Clinics, Iowa City, Iowa, USA
| | - Edgar A Samaniego
- Deparment of Neurosurgery, University of Iowa Hospitals and Clinics, Iowa City, Iowa, USA
- Deparment of Neurology, University of Iowa Hospitals and Clinics, Iowa City, Iowa, USA
| | - Daizo Ishii
- Deparment of Neurosurgery, University of Iowa Hospitals and Clinics, Iowa City, Iowa, USA
| | - Yongjun Lu
- Deparment of Neurosurgery, University of Iowa Hospitals and Clinics, Iowa City, Iowa, USA
| | - I Erol Sandalcioglu
- Deparment of Neurosurgery, Otto-von-Guericke University, Magdeburg, Saxony Anhalt, Germany
| | - Sylvia Saalfeld
- Deparment of Simulation and Graphics, University of Magdeburg, Magdeburg, Saxony Anhalt, Germany
- Research Campus STIMULATE, Magdeburg, Saxony Anhalt, Germany
| | - Philipp Berg
- Research Campus STIMULATE, Magdeburg, Saxony Anhalt, Germany
- Department of Fluid Dynamics and Technical Flows, University of Magdeburg, Magdeburg, Saxony Anhalt, Germany
| | - David M Hasan
- Deparment of Neurosurgery, University of Iowa Hospitals and Clinics, Iowa City, Iowa, USA
| |
Collapse
|
13
|
Identification of intima-to-media signals for flow-induced vascular remodeling using correlative gene expression analysis. Sci Rep 2021; 11:16142. [PMID: 34373496 PMCID: PMC8352890 DOI: 10.1038/s41598-021-95403-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2021] [Accepted: 07/26/2021] [Indexed: 12/12/2022] Open
Abstract
Changes in blood flow can induce arterial remodeling. Intimal cells sense flow and send signals to the media to initiate remodeling. However, the nature of such intima-media signaling is not fully understood. To identify potential signals, New Zealand white rabbits underwent bilateral carotid ligation to increase flow in the basilar artery or sham surgery (n = 2 ligated, n = 2 sham). Flow was measured by transcranial Doppler ultrasonography, vessel geometry was determined by 3D angiography, and hemodynamics were quantified by computational fluid dynamics. 24 h post-surgery, the basilar artery and terminus were embedded for sectioning. Intima and media were separately microdissected from the sections, and whole transcriptomes were obtained by RNA-seq. Correlation analysis of expression across all possible intima-media gene pairs revealed potential remodeling signals. Carotid ligation increased flow in the basilar artery and terminus and caused differential expression of 194 intimal genes and 529 medial genes. 29,777 intima-media gene pairs exhibited correlated expression. 18 intimal genes had > 200 medial correlates and coded for extracellular products. Gene ontology of the medial correlates showed enrichment of organonitrogen metabolism, leukocyte activation/immune response, and secretion/exocytosis processes. This demonstrates correlative expression analysis of intimal and medial genes can reveal novel signals that may regulate flow-induced arterial remodeling.
Collapse
|
14
|
İdil Soylu A, Uzunkaya F, Akan H. Anterior communicating artery aneurysms: Nonmodifiable morphological parameters associated with rupture risk. J Neuroimaging 2021; 31:940-946. [PMID: 34143925 DOI: 10.1111/jon.12896] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2021] [Revised: 05/20/2021] [Accepted: 05/25/2021] [Indexed: 11/29/2022] Open
Abstract
BACKGROUND AND PURPOSE The aim of this study was to investigate the relationship between arterial morphological parameters and the rupture risk of anterior communicating artery (AComA) aneurysms. METHODS A hospital database was retrospectively reviewed to identify patients with AComA aneurysms. Morphologic parameters were evaluated on the 3-dimensional computed tomography angiograms. The patients were divided into two groups as ruptured and unruptured. Patient age, sex, morphological parameters such as aneurysm height and weight, neck diameter, aspect ratio (AR), size ratio (SR), bifurcation angle, aneurysm shape, and diameters of the artery were statistically compared between two groups. RESULTS Ninety-five AComA aneurysms were analyzed in this study (60 ruptured and 35 unruptured). The aneurysm neck size (p = .005) and the diameter of the A1 segment of the ipsilateral anterior cerebral artery (i-A1) were smaller in the ruptured group than in the unruptured group (p = .001), but AR (p = .001) was higher. The number of patients with irregular shape aneurysm were higher in the ruptured group (p = .006). There was no significant difference between the two groups in terms of age, sex, aneurysm height and weight, bifurcation angle, and SR. Univariate logistic regression analysis showed that i-A1 segment diameter (odds ratio [OR]: -2.070, confidence interval [CI]: 0.030-0.531, p = .005), aneurysm neck diameter (OR: -0.409, CI: 0.491-0.899, p = .008), irregular shape (OR: 1.197, CI: 1.382-7.929, p = .007), and AR (OR: 0.880, CI: 1.315-4.417, p = .004) were significantly correlated with ruptured status. Multivariate regression analysis demonstrated that aneurysm neck diameter (OR: -0.457, CI: 0.410-0.977, p = .039) was the only independent variable for rupture. CONCLUSION AComA aneurysm rupture is more likely to occur in aneurysms with smaller i-A1 segment diameter, smaller aneurysm neck diameter, irregular aneurysm shape, and higher AR. Aneurysm neck diameter may be a more important determinant for rupture prediction.
Collapse
Affiliation(s)
- Ayşegül İdil Soylu
- Department of Radiology, Faculty of Medicine, Ondokuz Mayis University, Samsun, Turkey
| | - Fatih Uzunkaya
- Department of Radiology, Faculty of Medicine, Ondokuz Mayis University, Samsun, Turkey
| | - Hüseyin Akan
- Department of Radiology, Faculty of Medicine, Ondokuz Mayis University, Samsun, Turkey
| |
Collapse
|
15
|
Endogenous animal models of intracranial aneurysm development: a review. Neurosurg Rev 2021; 44:2545-2570. [PMID: 33501561 DOI: 10.1007/s10143-021-01481-w] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2020] [Revised: 01/05/2021] [Accepted: 01/18/2021] [Indexed: 12/13/2022]
Abstract
The pathogenesis and natural history of intracranial aneurysm (IA) remains poorly understood. To this end, animal models with induced cerebral vessel lesions mimicking human aneurysms have provided the ability to greatly expand our understanding. In this review, we comprehensively searched the published literature to identify studies that endogenously induced IA formation in animals. Studies that constructed aneurysms (i.e., by surgically creating a sac) were excluded. From the eligible studies, we reported information including the animal species, method for aneurysm induction, aneurysm definitions, evaluation methods, aneurysm characteristics, formation rate, rupture rate, and time course. Between 1960 and 2019, 174 articles reported endogenous animal models of IA. The majority used flow modification, hypertension, and vessel wall weakening (i.e., elastase treatment) to induce IAs, primarily in rats and mice. Most studies utilized subjective or qualitative descriptions to define experimental aneurysms and histology to study them. In general, experimental IAs resembled the pathobiology of the human disease in terms of internal elastic lamina loss, medial layer degradation, and inflammatory cell infiltration. After the early 2000s, many endogenous animal models of IA began to incorporate state-of-the-art technology, such as gene expression profiling and 9.4-T magnetic resonance imaging (MRI) in vivo imaging, to quantitatively analyze the biological mechanisms of IA. Future studies aimed at longitudinally assessing IA pathobiology in models that incorporate aneurysm growth will likely have the largest impact on our understanding of the disease. We believe this will be aided by high-resolution, small animal, survival imaging, in situ live-cell imaging, and next-generation omics technology.
Collapse
|
16
|
Zhang S, Shen Y, Zhou C, Zhu W, Zhang F, Hu J, Liu D, Lv M. Association between sleep duration and rupture of intracranial aneurysms: A single-center retrospective study. J Clin Neurosci 2020; 81:252-258. [DOI: 10.1016/j.jocn.2020.09.060] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2020] [Revised: 08/30/2020] [Accepted: 09/28/2020] [Indexed: 11/25/2022]
|
17
|
Sasaki T, Kakizawa Y, Yoshino M, Fujii Y, Yoroi I, Ichikawa Y, Horiuchi T, Hongo K. Numerical Analysis of Bifurcation Angles and Branch Patterns in Intracranial Aneurysm Formation. Neurosurgery 2020; 85:E31-E39. [PMID: 30137458 DOI: 10.1093/neuros/nyy387] [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] [Received: 11/09/2017] [Accepted: 07/24/2018] [Indexed: 11/14/2022] Open
Abstract
BACKGROUND Hemodynamic factors, especially wall shear stress (WSS), are generally thought to play an important role in intracranial aneurysm (IA) formation. IAs frequently occur at bifurcation apices, where the vessels are exposed to the impact of WSS. OBJECTIVE To elucidate the relationship between bifurcation geometry and WSS for IA formation. METHODS Twenty-one bifurcation models varying in branch angles and branch diameters were made with 3-dimensional computer-aided design software. In all models, the value of maximum WSS (WSSMAX), the area of high WSS (AREA), and the magnitude of wall shear force over AREA ($| {{{\vec{F}}_w}} |$) were investigated by the steady-flow simulation of computational fluid dynamics. RESULTS On the basis of statistical analysis, WSSMAX tended to be high when the bifurcation angle and/or branch diameter was small. AREA and $| {{{\vec{F}}_w}} |$ significantly increase as the bifurcation and/or the branch angle became larger. CONCLUSION The magnitude of WSS strongly correlated with bifurcation geometry. In addition to high WSS, AREA and $| {{{\vec{F}}_w}} |$ were thought to affect IA formation. Observed bifurcation geometry may predict IA formation. Large branch angles and small branch may increase the risk of IA formation.
Collapse
Affiliation(s)
- Tetsuo Sasaki
- Department of Neurosurgery, Shinshu University School of Medicine, Matsumoto, Japan
| | - Yukinari Kakizawa
- Department of Neurosurgery, Shinshu University School of Medicine, Matsumoto, Japan
| | - Masato Yoshino
- Institute of Engineering, Academic Assembly, Shinshu University, Nagano, Japan.,Institute of Carbon Science and Technology, Interdisciplinary Cluster for Cutting Edge Research, Shinshu University, Nagano, Japan
| | - Yasuhiro Fujii
- Department of Mechanical Systems Engineering, Shinshu University, Nagano, Japan
| | - Ikumi Yoroi
- Department of Mechanical Systems Engineering, Shinshu University, Nagano, Japan
| | - Yozo Ichikawa
- Department of Neurosurgery, Shinshu University School of Medicine, Matsumoto, Japan
| | - Tetsuyoshi Horiuchi
- Department of Neurosurgery, Shinshu University School of Medicine, Matsumoto, Japan
| | - Kazuhiro Hongo
- Department of Neurosurgery, Shinshu University School of Medicine, Matsumoto, Japan
| |
Collapse
|
18
|
Liu Z, Ajimu K, Yalikun N, Zheng Y, Xu F. Potential Therapeutic Strategies for Intracranial Aneurysms Targeting Aneurysm Pathogenesis. Front Neurosci 2019; 13:1238. [PMID: 31849575 PMCID: PMC6902030 DOI: 10.3389/fnins.2019.01238] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2019] [Accepted: 11/01/2019] [Indexed: 12/20/2022] Open
Abstract
Subarachnoid hemorrhage resulting from intracranial aneurysms (IAs) is associated with high rates of morbidity and mortality. Although trigger mechanisms in the pathogenesis of IAs have not been fully elucidated, accumulating evidence has demonstrated that inflammation acts as a critical contributor to aneurysm pathogenesis. IAs is initiated by disruption and dysfunction of endothelial cells (ECs) caused by abnormal wall shear stress (WSS). Subsequently, vascular inflammation can trigger a series of biochemical reactions resulting in vascular smooth muscle cell (VSMC) apoptosis and migration, accompanied by inflammatory cell infiltration, secretion of various cytokines, and inflammatory factors. These changes result in degradation of vascular wall, leading to the progression and eventual rupture of IAs. Increasing our knowledge of the pathogenesis of these lesions will offer physicians new options for prevention and treatment. In this study, we review aneurysmal pathogenesis to seek for safe, effective, and non-invasive therapeutic strategies.
Collapse
Affiliation(s)
- Zhao Liu
- Department of Neurosurgery, Jingjiang People's Hospital, Taizhou, China
| | - Kuerban Ajimu
- Department of Neurosurgery, First People's Hospital of Kashgar, Kashgar, China
| | - Naibijiang Yalikun
- Department of Neurosurgery, Hotan District People's Hospital, Hotan, China
| | - Yongtao Zheng
- Department of Neurosurgery, Shanghai Medical College, Huashan Hospital Fudan University, Shanghai, China
| | - Feng Xu
- Department of Neurosurgery, Shanghai Medical College, Huashan Hospital Fudan University, Shanghai, China.,Department of Neurosurgery, Kashgar Prefecture Second People's Hospital, Kashgar, China
| |
Collapse
|
19
|
Acuna A, Berman AG, Damen FW, Meyers BA, Adelsperger AR, Bayer KC, Brindise MC, Bungart B, Kiel AM, Morrison RA, Muskat JC, Wasilczuk KM, Wen Y, Zhang J, Zito P, Goergen CJ. Computational Fluid Dynamics of Vascular Disease in Animal Models. J Biomech Eng 2019; 140:2676341. [PMID: 29570754 DOI: 10.1115/1.4039678] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2017] [Indexed: 12/19/2022]
Abstract
Recent applications of computational fluid dynamics (CFD) applied to the cardiovascular system have demonstrated its power in investigating the impact of hemodynamics on disease initiation, progression, and treatment outcomes. Flow metrics such as pressure distributions, wall shear stresses (WSS), and blood velocity profiles can be quantified to provide insight into observed pathologies, assist with surgical planning, or even predict disease progression. While numerous studies have performed simulations on clinical human patient data, it often lacks prediagnosis information and can be subject to large intersubject variability, limiting the generalizability of findings. Thus, animal models are often used to identify and manipulate specific factors contributing to vascular disease because they provide a more controlled environment. In this review, we explore the use of CFD in animal models in recent studies to investigate the initiating mechanisms, progression, and intervention effects of various vascular diseases. The first section provides a brief overview of the CFD theory and tools that are commonly used to study blood flow. The following sections are separated by anatomical region, with the abdominal, thoracic, and cerebral areas specifically highlighted. We discuss the associated benefits and obstacles to performing CFD modeling in each location. Finally, we highlight animal CFD studies focusing on common surgical treatments, including arteriovenous fistulas (AVF) and pulmonary artery grafts. The studies included in this review demonstrate the value of combining CFD with animal imaging and should encourage further research to optimize and expand upon these techniques for the study of vascular disease.
Collapse
Affiliation(s)
- Andrea Acuna
- Weldon School of Biomedical Engineering, Purdue University, 206 S. Martin Jischke Drive, West Lafayette, IN 47907 e-mail:
| | - Alycia G Berman
- Weldon School of Biomedical Engineering, Purdue University, 206 S. Martin Jischke Drive, West Lafayette, IN 47907 e-mail:
| | - Frederick W Damen
- Weldon School of Biomedical Engineering, Purdue University, 206 S. Martin Jischke Drive, West Lafayette, IN 47907 e-mail:
| | - Brett A Meyers
- School of Mechanical Engineering, Purdue University, 585 Purdue Mall, West Lafayette, IN 47907 e-mail:
| | - Amelia R Adelsperger
- Weldon School of Biomedical Engineering, Purdue University, 206 S. Martin Jischke Drive, West Lafayette, IN 47907 e-mail:
| | - Kelsey C Bayer
- Weldon School of Biomedical Engineering, Purdue University, 206 S. Martin Jischke Drive, West Lafayette, IN 47907 e-mail:
| | - Melissa C Brindise
- School of Mechanical Engineering, Purdue University, 585 Purdue Mall, West Lafayette, IN 47907 e-mail:
| | - Brittani Bungart
- Weldon School of Biomedical Engineering, Purdue University, 206 S. Martin Jischke Drive, West Lafayette, IN 47907 e-mail:
| | - Alexander M Kiel
- Weldon School of Biomedical Engineering, Purdue University, 206 S. Martin Jischke Drive, West Lafayette, IN 47907 e-mail:
| | - Rachel A Morrison
- Weldon School of Biomedical Engineering, Purdue University, 206 S. Martin Jischke Drive, West Lafayette, IN 47907 e-mail:
| | - Joseph C Muskat
- Weldon School of Biomedical Engineering, Purdue University, 206 S. Martin Jischke Drive, West Lafayette, IN 47907 e-mail:
| | - Kelsey M Wasilczuk
- Weldon School of Biomedical Engineering, Purdue University, 206 S. Martin Jischke Drive, West Lafayette, IN 47907 e-mail:
| | - Yi Wen
- Department of Agricultural and Biological Engineering, Purdue University, 225 South University Street, West Lafayette, IN 47907 e-mail:
| | - Jiacheng Zhang
- School of Mechanical Engineering, Purdue University, 585 Purdue Mall, West Lafayette, IN 47907 e-mail:
| | - Patrick Zito
- Weldon School of Biomedical Engineering, Purdue University, 206 S. Martin Jischke Drive, West Lafayette, IN 47907 e-mail:
| | - Craig J Goergen
- ASME Membership Bioengineering Division, Weldon School of Biomedical Engineering, Purdue University, 206 S. Martin Jischke Drive, West Lafayette, IN 47907 e-mail:
| |
Collapse
|
20
|
Texakalidis P, Sweid A, Mouchtouris N, Peterson EC, Sioka C, Rangel-Castilla L, Reavey-Cantwell J, Jabbour P. Aneurysm Formation, Growth, and Rupture: The Biology and Physics of Cerebral Aneurysms. World Neurosurg 2019; 130:277-284. [DOI: 10.1016/j.wneu.2019.07.093] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2019] [Revised: 07/08/2019] [Accepted: 07/09/2019] [Indexed: 12/18/2022]
|
21
|
Qiu T, Jin G, Bao W, Lu H. Intercorrelations of morphology with hemodynamics in intracranial aneurysms in computational fluid dynamics. ACTA ACUST UNITED AC 2019; 22:205-212. [PMID: 28678215 PMCID: PMC5946365 DOI: 10.17712/nsj.2017.3.20160452] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Objective: To measure morphological indices and wall shear stress (WSS) of aneurysms and parent artery surface in order to explore the relationship of morphological characteristics and WSS. Methods: Data from 47 events of consecutive cerebral saccular aneurysms from 39 patients which were referred to the interventional Neuroradiology service of the Shaoxing People’s Hospital, Shaoxing, China between 2014 April and 2015 August. Wall shear stress and wall pressure (WP) of the pre-aneurysm, aneurysm and near vessel (<1.0 cm) surface were obtained. Correlation analysis was carried between morphological parameters and WSS and its ratio. WSS, WP, intra-aneurysmal flow pattern, and location of aneurysms were analyzed. Results: Impaction zone from inflow jet was located in the distal neck part of aneurysm with high WSS in 36 aneurysms (76.6%). There were significant differences in WSS between pre-aneurysm surface and near vessel (p<0.001), aneurysm (p<0.001), aneurysm and near vessel (p<0.001). Significant correlations were found between aneurysm WSS and aspect ratio (r=-0.296), aneurysm-artery WSS ratio and size ratio (r=-0.322), aspect ratio (r=-0.416). Conclusion: Uneven WSS distributes in the various part of the pre-aneurysm vessel. The impaction zone from inflow jet is located in the distal neck of aneurysm. Aspect and size ratios can effect aneurysm WSS
Collapse
Affiliation(s)
- Tianlun Qiu
- Department of Neurosurgery, Shaoxing People`s Hospital, Shaoxing, Zhejiang, China
| | | | | | | |
Collapse
|
22
|
İdil Soylu A, Ozturk M, Akan H. Can vessel diameters, diameter ratios, and vessel angles predict the development of anterior communicating artery aneurysms: A morphological analysis. J Clin Neurosci 2019; 68:250-255. [PMID: 31358430 DOI: 10.1016/j.jocn.2019.07.024] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2019] [Accepted: 07/05/2019] [Indexed: 12/17/2022]
Abstract
The anterior communicating artery (AcomA) junction is the most common location for cerebral aneurysms. This might because of increased vascular wall stress due to the complex structure of the junction. The aim of this study investigate the effect of morphological parameters in the development of AcomA aneurysms. This retrospective study was approved by the institutional ethics committee. A retrospective analysis of our hospital database was performed to identify patients with AcomA aneurysms. Patients with normal computed tomography angiography (CTA) examinations were enrolled in the study as the control group. The control group was similar to the patient group in gender and age. Morphological parameters (vessel diameters, vessel diameter ratios, and vessel angles) on the same side (ipsilateral) and on the opposite side (contralateral) of the patients with aneurysm, and morphological parameters of the control group were compared. A total of 171 subjects were involved in the study (86 patients with aneurysms and 85 patients in the control group). Multivariate regression analysis revealed that the ipsilateral A1-A2 angle (OR: 0.932; 95% CI: 0.903-0.961; p < 0.001), the ipsilateral A1/A2 vessel diameter ratio (OR: 27.725; 95% CI: 1.715-448.139; p = 0.019), and the contralateral internal carotid artery (ICA)/A1 ratio (OR: 11.817; 95% CI: 2.617-53.355; p = 0.001) were significant morphological predictors for developing an aneurysm. An increased contralateral ICA/A1 ratio, an increased ipsilateral A1/A2 vessel diameter ratio, and a narrow bifurcation angle are significant predictors for developing an aneurysm. Therefore, in patients with clinical risk factors these parameters may be interpreted as additional morphological risk factors for developing an aneurysm.
Collapse
Affiliation(s)
- Ayşegül İdil Soylu
- Department of Radiology, Ondokuz Mayis University Faculty of Medicine, Samsun, Turkey.
| | - Mesut Ozturk
- Department of Radiology, Ondokuz Mayis University Faculty of Medicine, Samsun, Turkey
| | - Hüseyin Akan
- Department of Radiology, Ondokuz Mayis University Faculty of Medicine, Samsun, Turkey
| |
Collapse
|
23
|
Shakur SF, Alaraj A, Mendoza-Elias N, Osama M, Charbel FT. Hemodynamic characteristics associated with cerebral aneurysm formation in patients with carotid occlusion. J Neurosurg 2019; 130:917-922. [PMID: 29726778 DOI: 10.3171/2017.11.jns171794] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2017] [Accepted: 11/10/2017] [Indexed: 11/06/2022]
Abstract
OBJECTIVE The pathogenesis of cerebral aneurysms in patients with internal carotid artery (ICA) occlusion is hypothesized to be hemodynamic. For the first time, the authors quantify the hemodynamic characteristics associated with aneurysm formation in patients with ICA occlusion. METHODS Records of patients with unilateral ICA stenosis or occlusion ≥ 90% who underwent hemodynamic assessment before treatment using quantitative MR angiography were retrospectively reviewed. The patients were classified into 2 groups based on the presence or absence of aneurysms. The hemodynamic parameters of flow volume rate, flow velocity, and wall shear stress (WSS) were measured in each vessel supplying collateral flow-bilateral A1 segments and bilateral posterior communicating arteries-and then compared between the groups. RESULTS A total of 36 patients were included (8 with and 28 without aneurysms). The mean flow (72.3 vs 48.9 ml/min, p = 0.10), flow velocity (21.1 vs 12.7 cm/sec, p = 0.006), and WSS (22.0 vs 12.3 dynes/cm2, p = 0.003) were higher in the A1 segment contralateral to the side of the patent ICA in patients with versus without aneurysms. All de novo or growing aneurysms in our cohort were located on the anterior communicating artery (ACoA) or P1 segment. CONCLUSIONS Flow velocity and WSS are significantly higher across the ACoA in patients who harbor an aneurysm, and de novo or growing aneurysms are often located on collateral vessels. Thus, robust primary collaterals after ICA occlusion may be a contributing factor in cerebral aneurysm formation.
Collapse
|
24
|
Miyata H, Shimizu K, Koseki H, Abekura Y, Kataoka H, Miyamoto S, Nozaki K, Narumiya S, Aoki T. Real-time Imaging of an Experimental Intracranial Aneurysm in Rats. Neurol Med Chir (Tokyo) 2018; 59:19-26. [PMID: 30555120 PMCID: PMC6350001 DOI: 10.2176/nmc.oa.2018-0197] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Subarachnoid hemorrhage due to rupture of a pre-existing intracranial aneurysm has quite a poor outcome in spite of intensive medical care. Hemodynamic stress loaded on intracranial arterial walls is considered as a trigger and a regulator of formation and progression of the disease, but how intracranial arterial walls or intracranial aneurysm walls behave under hemodynamic stress loading remains unclear. The purpose of this study was to visualize and analyze the wall motion of intracranial aneurysms to detect a pathological flow condition. We subjected a transgenic rat line, in which endothelial cells are specifically visualized by expression of a green fluorescent protein, to an intracranial aneurysm model and observed a real-time motion of intracranial arterial walls or intracranial aneurysm walls by a multiphoton laser confocal microscopy. The anterior cerebral artery–olfactory artery bifurcation was surgically exposed for the monitoring. First, we observed the proper flow-dependent physiological dilatation of a contralateral intracranial artery in response to increase of blood flow by one side of carotid ligation. Next, we observed intracranial aneurysm lesions induced in a rat model and confirmed that a wall motion of the dome was static, whereas that of the neck was more dynamic in response to pulsation of blood flow. We successfully monitored a real-time motion of intracranial aneurysm walls. Findings obtained from such a real-time imaging will provide us many insights especially about the correlation of mechanical force and the pathogenesis of the disease and greatly promote our understanding of the disease.
Collapse
Affiliation(s)
- Haruka Miyata
- Department of Molecular Pharmacology, Research Institute, National Cerebral and Cardiovascular Center.,Department of Neurosurgery, Shiga University of Medical Science.,Core Research for Evolutional Science and Technology (CREST) from Japan Agency for Medical Research and Development (AMED), National Cerebral and Cardiovascular Center
| | - Kampei Shimizu
- Department of Molecular Pharmacology, Research Institute, National Cerebral and Cardiovascular Center.,Department of Neurosurgery, Kyoto University Graduate School of Medicine
| | - Hirokazu Koseki
- Department of Molecular Pharmacology, Research Institute, National Cerebral and Cardiovascular Center.,Core Research for Evolutional Science and Technology (CREST) from Japan Agency for Medical Research and Development (AMED), National Cerebral and Cardiovascular Center.,Department of Neurosurgery, Tokyo Women's Medical University Medical Center East
| | - Yu Abekura
- Department of Molecular Pharmacology, Research Institute, National Cerebral and Cardiovascular Center.,Department of Neurosurgery, Kyoto University Graduate School of Medicine
| | - Hiroharu Kataoka
- Department of Neurosurgery, Kyoto University Graduate School of Medicine
| | - Susumu Miyamoto
- Department of Neurosurgery, Kyoto University Graduate School of Medicine
| | - Kazuhiko Nozaki
- Department of Neurosurgery, Shiga University of Medical Science
| | - Shuh Narumiya
- Alliance Laboratory for Advanced Medical Research, Medical Innovation Center, Kyoto University Graduate School of Medicine
| | - Tomohiro Aoki
- Department of Molecular Pharmacology, Research Institute, National Cerebral and Cardiovascular Center.,Core Research for Evolutional Science and Technology (CREST) from Japan Agency for Medical Research and Development (AMED), National Cerebral and Cardiovascular Center.,Alliance Laboratory for Advanced Medical Research, Medical Innovation Center, Kyoto University Graduate School of Medicine
| |
Collapse
|
25
|
Matsukawa H, Kamiyama H, Noda K, Ota N, Takahashi O, Shonai T, Tokuda S, Tanikawa R. Embryological basilar apex disposition as a risk factor of basilar apex aneurysm. J Clin Neurosci 2018; 58:79-82. [PMID: 30327221 DOI: 10.1016/j.jocn.2018.10.004] [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: 01/03/2018] [Revised: 09/10/2018] [Accepted: 10/03/2018] [Indexed: 10/28/2022]
Abstract
The pathogenesis of basilar apex aneurysm (BAA) are still poorly understood. Embryologically, basilar apex anatomical disposition is formed by the fusion of both caudal internal carotid divisions on the midline. To compare basilar apex morphology by embryological classification among patients with BAAs, anterior circulation aneurysms (ACAs), and controls. Prospectively collected data of 47 consecutive patients with unruptured BAAs (42 females and five males), age- and gender-matched 47 patients with unruptured ACAs, and 47 controls without any aneurysms were analyzed. Based on embryology, basilar apex morphology was classified into symmetric cranial fusion (SCrF), symmetric caudal fusion, and asymmetric fusion type. Posterior communicating artery (Pcom) was classified into hypoplastic, adult, or fetal type. The asymmetrical Pcom was defined as bilaterally different type Pcom. The ACAs located at the anterior communicating artery (n = 18), paraclinoid portion (n = 12), middle cerebral artery (n = 8), anterior cerebral artery (n = 5), the top of internal carotid artery (n = 2), and anterior choroidal artery (n = 2). Compared with the ACA group and controls, smoking, asymmetrical Pcom (fetal and adult type), and SCrF type were more prevalent in patients with BAAs by residual analysis. The multinomial logistic regression comparative analysis demonstrated that SCrF type was associated with BAAs (vs. ACA group; odds ratio, 13; 95% confidence interval, 3.8-41 and vs. controls; odds ratio, 25; 95% confidence interval, 5.4-121). The assessment of basilar apex morphology may aid in the understanding of the pathogenesis of BAA and the prediction of BAA formation.
Collapse
Affiliation(s)
- Hidetoshi Matsukawa
- Department of Neurosurgery, Stroke Center, Teishinkai Hospital, Sapporo, Japan
| | - Hiroyasu Kamiyama
- Department of Neurosurgery, Stroke Center, Teishinkai Hospital, Sapporo, Japan
| | - Kosumo Noda
- Department of Neurosurgery, Stroke Center, Teishinkai Hospital, Sapporo, Japan
| | - Nakao Ota
- Department of Neurosurgery, Stroke Center, Teishinkai Hospital, Sapporo, Japan
| | - Osamu Takahashi
- Center for Clinical Epidemiology, Internal Medicine, St. Luke's International Hospital, Tokyo, Japan
| | - Takaharu Shonai
- Department of Radiology, Teishinkai Hospital, Sapporo, Japan
| | - Sadahisa Tokuda
- Department of Neurosurgery, Stroke Center, Teishinkai Hospital, Sapporo, Japan
| | - Rokuya Tanikawa
- Department of Neurosurgery, Stroke Center, Teishinkai Hospital, Sapporo, Japan.
| |
Collapse
|
26
|
Diagbouga MR, Morel S, Bijlenga P, Kwak BR. Role of hemodynamics in initiation/growth of intracranial aneurysms. Eur J Clin Invest 2018; 48:e12992. [PMID: 29962043 DOI: 10.1111/eci.12992] [Citation(s) in RCA: 45] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/28/2018] [Revised: 06/12/2018] [Accepted: 06/29/2018] [Indexed: 12/31/2022]
Abstract
BACKGROUND Intracranial aneurysm (IA) is a disease of the vascular wall resulting in abnormal enlargement of the vessel lumen. It is a common pathology with a prevalence of 2%-3% in the adult population. IAs are mostly small, quiescent and asymptomatic; yet, upon rupture, severe brain damage or even death is frequently encountered. In addition to clinical factors, hemodynamic forces, mainly wall shear stress (WSS), have been associated with the initiation of IAs and possibly with their risk of rupture. However, the mechanism by which WSS contributes to aneurysm growth and rupture is not completely understood. DESIGN PubMed and Ovid MEDLINE databases were searched. In addition, key review articles were screened for relevant original publications. RESULTS Current knowledge about the relation between WSS and IA has been obtained from both computational fluid dynamic studies in patients and experimental models of IA formation and growth. It is increasingly recognized that a high wall shear stress (gradient) participates to IA formation and that both low and high WSS can drive IA growth. Primary cilia (PC) play an important role as mechanosensors as patients with polycystic kidney disease, which is characterized by the absence or dysfunction of PC, have increased risk to develop IAs as well as increased risk of rupture. CONCLUSION Wall shear stress is a key player in IA initiation and progression. It is involved in vascular wall remodelling and inflammation, processes underlying aneurysm pathophysiology.
Collapse
Affiliation(s)
- Mannekomba R Diagbouga
- Department of Pathology and Immunology, Faculty of Medicine, University of Geneva, Geneva, Switzerland
| | - Sandrine Morel
- Department of Pathology and Immunology, Faculty of Medicine, University of Geneva, Geneva, Switzerland.,Neurosurgery Division, Department of Clinical Neurosciences, Faculty of Medicine, Geneva University Hospitals, Geneva, Switzerland
| | - Philippe Bijlenga
- Neurosurgery Division, Department of Clinical Neurosciences, Faculty of Medicine, Geneva University Hospitals, Geneva, Switzerland
| | - Brenda R Kwak
- Department of Pathology and Immunology, Faculty of Medicine, University of Geneva, Geneva, Switzerland
| |
Collapse
|
27
|
Cooper S, Emmott A, McDonald KK, Campeau MA, Leask RL. Increased MMP activity in curved geometries disrupts the endothelial cell glycocalyx creating a proinflammatory environment. PLoS One 2018; 13:e0202526. [PMID: 30138400 PMCID: PMC6107195 DOI: 10.1371/journal.pone.0202526] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2018] [Accepted: 08/03/2018] [Indexed: 12/03/2022] Open
Abstract
Wall shear stress gradients (WSSGs) induce an inflammatory phenotype in endothelial cells (ECs) which is hypothesized to be mediated by mechanotransduction through the EC glycocalyx (GCX). We used a three-dimensional in vitro cell culture model with a 180o curved geometry to investigate if WSSGs created by curvature can cause EC inflammation and disruption of the GCX. The hydrodynamics of the model elicited a morphological response in ECs as well as a pattern of leukocyte adhesion towards the inner wall of curvature that was attenuated with enzymatic removal of GCX components. GCX degradation was also observed in regions of curvature which corresponded to increased activity of MMPs. Together, these results support the hypothesis that the EC GCX is involved in mechanotransduction of WSSGs and that components of the GCX are regulated by MMP activity in regions of curvature.
Collapse
Affiliation(s)
- Scott Cooper
- Department of Chemical Engineering, McGill University, Montréal, Quebec, Canada
| | - Alexander Emmott
- Department of Chemical Engineering, McGill University, Montréal, Quebec, Canada
- Montreal Heart Institute, Montréal, Quebec, Canada
| | - Karli K. McDonald
- Department of Chemical Engineering, McGill University, Montréal, Quebec, Canada
| | | | - Richard L. Leask
- Department of Chemical Engineering, McGill University, Montréal, Quebec, Canada
- Montreal Heart Institute, Montréal, Quebec, Canada
- * E-mail:
| |
Collapse
|
28
|
Signorelli F, Sela S, Gesualdo L, Chevrel S, Tollet F, Pailler-Mattei C, Tacconi L, Turjman F, Vacca A, Schul DB. Hemodynamic Stress, Inflammation, and Intracranial Aneurysm Development and Rupture: A Systematic Review. World Neurosurg 2018; 115:234-244. [DOI: 10.1016/j.wneu.2018.04.143] [Citation(s) in RCA: 53] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2018] [Revised: 04/18/2018] [Accepted: 04/19/2018] [Indexed: 10/17/2022]
|
29
|
Song J, Zhu F, Qian Y, Ou C, Cai J, Zou X, Wu Z, Zhu W, Chen L, Mao Y. Morphological and Hemodynamic Differences Between Aneurysmal Middle Cerebral Artery Bifurcation and Contralateral Nonaneurysmal Anatomy. Neurosurgery 2018; 81:779-786. [PMID: 28379506 DOI: 10.1093/neuros/nyx093] [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: 01/25/2016] [Accepted: 02/10/2017] [Indexed: 11/13/2022] Open
Abstract
BACKGROUND The morphological and hemodynamic features differ between middle cerebral artery (MCA) bifurcations with and without aneurysms. OBJECTIVE To investigate the morphological and hemodynamic differences between aneurysmal MCA bifurcation and contralateral nonaneurysmal anatomy. METHODS Computed tomography angiography of 36 patients with unilateral small saccular MCA bifurcation aneurysms was evaluated. The parent-daughter angles (φ1 for larger branch and φ2 for smaller branch), bifurcation angle (φ = φ1 + φ2), inclination angle (γ angle), and their relationships with the MCA bifurcation locations were analyzed. Computational fluid dynamics simulation was performed in 6 cases to explore the hemodynamics influenced by the bifurcation morphology. RESULTS The φ angle was significantly higher in aneurysmal than contralateral nonaneurysmal bifurcations (160.8° ± 31.0° vs 99.0° ± 19.2°, respectively; P = .000); the φ1, φ2, and γ angles were also higher. However, by regression analysis combined with MCA bifurcation locations, only the φ angle might be associated with the aneurysm presence (odds ratio = 1.120, 95% confidence interval = 1.059-1.185) and a φ angle cut-off of 124.8° was established. Computational fluid dynamics simulation demonstrated that flow resistance of the wider aneurysmal MCA bifurcation was significantly higher than that on the contralateral side. CONCLUSION A larger φ angle was more prevalent in aneurysmal than nonaneurysmal MCA bifurcations, and the higher flow resistance caused by the larger φ angle might be a potential hemodynamic factor associated with MCA aneurysm presence.
Collapse
Affiliation(s)
- Jianping Song
- Department of Neurosurgery, Huashan Hospital, Fudan University, Shanghai, China
| | - Fengping Zhu
- Department of Neurosurgery, Huashan Hospital, Fudan University, Shanghai, China.,Department of Biomedical Sciences, Faculty of Medicine and Health Sciences, Macquarie University, Sydney, Australia
| | - Yi Qian
- Department of Biomedical Sciences, Faculty of Medicine and Health Sciences, Macquarie University, Sydney, Australia
| | - Chubin Ou
- Department of Mechanical and Aerospace Engineering, Hong Kong University of Science and Technology, Hong Kong, China
| | - Jiajun Cai
- Department of Neurosurgery, Huashan Hospital, Fudan University, Shanghai, China
| | - Xiang Zou
- Department of Neurosurgery, Huashan Hospital, Fudan University, Shanghai, China
| | - Zehan Wu
- Department of Neurosurgery, Huashan Hospital, Fudan University, Shanghai, China
| | - Wei Zhu
- Department of Neurosurgery, Huashan Hospital, Fudan University, Shanghai, China
| | - Liang Chen
- Department of Neurosurgery, Huashan Hospital, Fudan University, Shanghai, China
| | - Ying Mao
- Department of Neurosurgery, Huashan Hospital, Fudan University, Shanghai, China
| |
Collapse
|
30
|
Terashima M, Miura Y, Ishida F, Toma N, Araki T, Shimosaka S, Kanamaru K, Suzuki H. One-stage Stent-assisted Coil Embolization for Rupture-side-unknown Bilateral Vertebral Artery Dissecting Aneurysms in an Acute Stage: A Case Report. NMC Case Rep J 2018; 5:45-49. [PMID: 29725567 PMCID: PMC5930239 DOI: 10.2176/nmccrj.cr.2017-0109] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2017] [Accepted: 07/31/2017] [Indexed: 11/20/2022] Open
Abstract
Bilateral vertebral artery dissecting aneurysms (VADAs) with subarachnoid hemorrhage (SAH) are rare and their management is still challenging. In this report, we successfully performed one-stage stent-assisted coil embolization (SAC) for bilateral VADAs with SAH in an acute stage, because the ruptured side could not be diagnosed. A 47-year-old woman presented with a sudden onset of headache without laterality, and left-side dominant SAH with bilateral VADAs was noted on computed tomography (CT) scans. The size of aneurysmal dome and neck was similar between the two VADAs, and a bleb was observed only on the right VADA. In computational fluid dynamics (CFD) simulations, findings of wall shear stress (WSS), normalized WSS, and WSS gradient suggested that the left VADA was ruptured, while the oscillatory shear index and aneurysm formation indicator suggested the opposite-side one to be ruptured. Thus, we could not determine which VADA was ruptured by clinical data and CFD analyses. Therefore, we performed simultaneous treatment for the bilateral VADAs by using SAC technique 8 h after the onset under dual antiplatelet and anticoagulation therapies. There was no evidence of rebleeding and stent thrombosis. Stent thrombosis was monitored by duplex color-coded ultrasonography after the intervention. She was discharged without neurological deficits, and 6-month follow-up cerebral angiography demonstrated no recanalization of VADAs. This is the first report showing bilateral VADAs with SAH treated by one-stage SAC within 24 h of SAH, and the potential risks are discussed.
Collapse
Affiliation(s)
- Mio Terashima
- Department of Neurosurgery, Mie University Graduate School of Medicine, Tsu, Mie, Japan
| | - Yoichi Miura
- Department of Neurosurgery, Suzuka Kaisei Hospital, Suzuka, Mie, Japan
| | - Fujimaro Ishida
- Department of Neurosurgery, Mie Chuo Medical Center, National Hospital Organization, Tsu, Mie, Japan
| | - Naoki Toma
- Department of Neurosurgery, Mie University Graduate School of Medicine, Tsu, Mie, Japan
| | - Tomohiro Araki
- Department of Neurosurgery, Suzuka Kaisei Hospital, Suzuka, Mie, Japan
| | - Shinichi Shimosaka
- Department of Neurosurgery, Mie Chuo Medical Center, National Hospital Organization, Tsu, Mie, Japan
| | - Kenji Kanamaru
- Department of Neurosurgery, Suzuka Kaisei Hospital, Suzuka, Mie, Japan
| | - Hidenori Suzuki
- Department of Neurosurgery, Mie University Graduate School of Medicine, Tsu, Mie, Japan
| |
Collapse
|
31
|
Pawlowska E, Szczepanska J, Wisniewski K, Tokarz P, Jaskólski DJ, Blasiak J. NF-κB-Mediated Inflammation in the Pathogenesis of Intracranial Aneurysm and Subarachnoid Hemorrhage. Does Autophagy Play a Role? Int J Mol Sci 2018; 19:E1245. [PMID: 29671828 PMCID: PMC5979412 DOI: 10.3390/ijms19041245] [Citation(s) in RCA: 39] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2018] [Revised: 04/13/2018] [Accepted: 04/17/2018] [Indexed: 12/12/2022] Open
Abstract
The rupture of saccular intracranial aneurysms (IA) is the commonest cause of non-traumatic subarachnoid hemorrhage (SAH)—the most serious form of stroke with a high mortality rate. Aneurysm walls are usually characterized by an active inflammatory response, and NF-κB (nuclear factor kappa-light-chain-enhancer of activated B cells) has been identified as the main transcription factor regulating the induction of inflammation-related genes in IA lesions. This transcription factor has also been related to IA rupture and resulting SAH. We and others have shown that autophagy interacts with inflammation in many diseases, but there is no information of such interplay in IA. Moreover, NF-κB, which is a pivotal factor controlling inflammation, is regulated by autophagy-related proteins, and autophagy is regulated by NF-κB signaling. It was also shown that autophagy mediates the normal functioning of vessels, so its disturbance can be associated with vessel-related disorders. Early brain injury, delayed brain injury, and associated cerebral vasospasm are among the most serious consequences of IA rupture and are associated with impaired function of the autophagy⁻lysosomal system. Further studies on the role of the interplay between autophagy and NF-κB-mediated inflammation in IA can help to better understand IA pathogenesis and to identify IA patients with an increased SAH risk.
Collapse
Affiliation(s)
- Elzbieta Pawlowska
- Department of Orthodontics, Medical University of Lodz, 92-216 Lodz, Poland.
| | - Joanna Szczepanska
- Department of Pediatric Dentistry, Medical University of Lodz, 92-216 Lodz, Poland.
| | - Karol Wisniewski
- Department of Neurosurgery and Neurooncology, Medical University of Lodz, Barlicki University Hospital, Kopcinskiego 22, 90-153 Lodz, Poland.
| | - Paulina Tokarz
- Department of Molecular Genetics, Faculty of Biology and Environmental Protection, University of Lodz, 90-236 Lodz, Poland.
| | - Dariusz J Jaskólski
- Department of Neurosurgery and Neurooncology, Medical University of Lodz, Barlicki University Hospital, Kopcinskiego 22, 90-153 Lodz, Poland.
| | - Janusz Blasiak
- Department of Molecular Genetics, Faculty of Biology and Environmental Protection, University of Lodz, 90-236 Lodz, Poland.
| |
Collapse
|
32
|
Watanabe T, Isoda H, Takehara Y, Terada M, Naito T, Kosugi T, Onishi Y, Tanoi C, Izumi T. Hemodynamic vascular biomarkers for initiation of paraclinoid internal carotid artery aneurysms using patient-specific computational fluid dynamic simulation based on magnetic resonance imaging. Neuroradiology 2018. [PMID: 29520642 DOI: 10.1007/s00234-018-2002-8] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
PURPOSE We performed computational fluid dynamics (CFD) for patients with and without paraclinoid internal carotid artery (ICA) aneurysms to evaluate the distribution of vascular biomarkers at the aneurysm initiation sites of the paraclinoid ICA. METHODS This study included 35 patients who were followed up for aneurysms using 3D time of flight (TOF) magnetic resonance angiography (MRA) and 3D cine phase-contrast MR imaging. Fifteen affected ICAs were included in group A with the 15 unaffected contralateral ICAs in group B. Thirty-three out of 40 paraclinoid ICAs free of aneurysms and arteriosclerotic lesions were included in group C. We deleted the aneurysms in group A based on the 3D TOF MRA dataset. We performed CFD based on MR data set and obtained wall shear stress (WSS), its derivatives, and streamlines. We qualitatively evaluated their distributions at and near the intracranial aneurysm initiation site among three groups. We also calculated and compared the normalized highest (nh-) WSS and nh-spatial WSS gradient (SWSSG) around the paraclinoid ICA among three groups. RESULTS High WSS and SWSSG distribution were observed at and near the aneurysm initiation site in group A. High WSS and SWSSG were also observed at similar locations in group B and group C. However, nh-WSS and nh-SWSSG were significantly higher in group A than in group C, and nh-SWSSG was significantly higher in group A than in group B. CONCLUSION Our findings indicated that nh-WSS and nh-SWSSG were good biomarkers for aneurysm initiation in the paraclinoid ICA.
Collapse
Affiliation(s)
- Tomoya Watanabe
- Department of Radiological and Medical Laboratory Sciences, Nagoya University Graduate School of Medicine, 1-20, Daikominami 1-chome, Higashi-ku, Nagoya, Aichi, 461-8673, Japan.,Division of Clinical Radiology Service, Kyoto University Hospital, 54 Kawaharacho, Shogoin, Sakyo-ku, Kyoto, 606-8507, Japan
| | - Haruo Isoda
- Department of Radiological and Medical Laboratory Sciences, Nagoya University Graduate School of Medicine, 1-20, Daikominami 1-chome, Higashi-ku, Nagoya, Aichi, 461-8673, Japan. .,Brain & Mind Research Center, Nagoya University, 1-20, Daikominami 1-chome, Higashi-ku, Nagoya, Aichi, 461-8673, Japan.
| | - Yasuo Takehara
- Department of Fundamental Development for Advanced Low Invasive Diagnostic Imaging, Nagoya University, Graduate School of Medicine, 65 Tsurumai-cho, Showa-ku, Nagoya, Aichi, 466-8550, Japan.,Department of Radiology, Hamamatsu University Hospital, 1-20-1 Handayama, Higashi-ku, Hamamatsu, Shizuoka, 431-3192, Japan
| | - Masaki Terada
- Department of Diagnostic Radiological Technology, Iwata City Hospital, 512-3 Okubo, Iwata, Shizuoka, 438-8550, Japan
| | - Takehiro Naito
- Department of Neurosurgery, Komaki City Hospital, 1-20 Jobushi, Komaki, Aichi, 485-8520, Japan.,Department of Neurosurgery, Iwata City Hospital, 512-3 Okubo, Iwata, Shizuoka, 438-8550, Japan
| | - Takafumi Kosugi
- Renaissance of Technology Corporation, 1-4-10 Shinmiyakoda Kita-ku, Hamamatsu, Shizuoka, 431-2103, Japan
| | - Yuki Onishi
- Department of Systems and Control Engineering, School of Engineering, Tokyo Institute of Technology, 2-12-1-W8-36, O-okayama, Meguro-ku, Tokyo, 152-8550, Japan
| | - Chiharu Tanoi
- Department of Neurosurgery, Iwata City Hospital, 512-3 Okubo, Iwata, Shizuoka, 438-8550, Japan
| | - Takashi Izumi
- Department of Neurosurgery, Nagoya University Graduate School of Medicine, 65 Tsurumai-cho, Showa-ku, Nagoya, Aichi, 466-8550, Japan
| |
Collapse
|
33
|
Varble N, Trylesinski G, Xiang J, Snyder K, Meng H. Identification of vortex structures in a cohort of 204 intracranial aneurysms. J R Soc Interface 2018; 14:rsif.2017.0021. [PMID: 28539480 DOI: 10.1098/rsif.2017.0021] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2017] [Accepted: 04/27/2017] [Indexed: 12/28/2022] Open
Abstract
An intracranial aneurysm (IA) is a cerebrovascular pathology that can lead to death or disability if ruptured. Abnormal wall shear stress (WSS) has been associated with IA growth and rupture, but little is known about the underlying flow physics related to rupture-prone IAs. Previous studies, based on analysis of a few aneurysms or partial views of three-dimensional vortex structures, suggest that rupture is associated with complex vortical flow inside IAs. To further elucidate the relevance of vortical flow in aneurysm pathophysiology, we studied 204 patient IAs (56 ruptured and 148 unruptured). Using objective quantities to identify three-dimensional vortex structures, we investigated the characteristics associated with aneurysm rupture and if these features correlate with previously proposed WSS and morphological characteristics indicative of IA rupture. Based on the Q-criterion definition of a vortex, we quantified the degree of the aneurysmal region occupied by vortex structures using the volume vortex fraction (vVF) and the surface vortex fraction (sVF). Computational fluid dynamics simulations showed that the sVF, but not the vVF, discriminated ruptured from unruptured aneurysms. Furthermore, we found that the near-wall vortex structures co-localized with regions of inflow jet breakdown, and significantly correlated to previously proposed haemodynamic and morphologic characteristics of ruptured IAs.
Collapse
Affiliation(s)
- Nicole Varble
- Department of Mechanical and Aerospace Engineering, University at Buffalo, State University of New York, Buffalo, NY, USA.,Toshiba Stroke and Vascular Research Center, University at Buffalo, State University of New York, Buffalo, NY, USA
| | - Gabriel Trylesinski
- Department of Mechanical and Aerospace Engineering, University at Buffalo, State University of New York, Buffalo, NY, USA.,Toshiba Stroke and Vascular Research Center, University at Buffalo, State University of New York, Buffalo, NY, USA
| | - Jianping Xiang
- Toshiba Stroke and Vascular Research Center, University at Buffalo, State University of New York, Buffalo, NY, USA.,Department of Neurosurgery, University at Buffalo, State University of New York, Buffalo, NY, USA
| | - Kenneth Snyder
- Toshiba Stroke and Vascular Research Center, University at Buffalo, State University of New York, Buffalo, NY, USA.,Department of Neurosurgery, University at Buffalo, State University of New York, Buffalo, NY, USA.,Department of Radiology, University at Buffalo, State University of New York, Buffalo, NY, USA
| | - Hui Meng
- Department of Mechanical and Aerospace Engineering, University at Buffalo, State University of New York, Buffalo, NY, USA .,Toshiba Stroke and Vascular Research Center, University at Buffalo, State University of New York, Buffalo, NY, USA.,Department of Neurosurgery, University at Buffalo, State University of New York, Buffalo, NY, USA.,Department of Biomedical Engineering, University at Buffalo, State University of New York, Buffalo, NY, USA
| |
Collapse
|
34
|
Stenosis Hemodynamics Disrupt the Endothelial Cell Glycocalyx by MMP Activity Creating a Proinflammatory Environment. Ann Biomed Eng 2017; 45:2234-2243. [PMID: 28474270 DOI: 10.1007/s10439-017-1846-0] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2017] [Accepted: 04/26/2017] [Indexed: 12/20/2022]
Abstract
Hemodynamic forces are known to be able to induce an inflammatory phenotype in endothelial cells (ECs). The EC glycocalyx (GCX) is a dynamic structure which is regulated in response to different stimuli and hypothesized as an important contributor to the mechanotransduction of wall shear stresses (WSS). In this work, we used a three dimensional in vitro EC culture model with a 50% asymmetric stenosis to investigate degradation of the GCX by increased matrix metalloproteinase (MMP) activity in regions of WSS gradients and how this degradation might create a proinflammatory environment. Experiments showed GCX degradation was observed in regions of WSSGs created by a 50% asymmetric stenosis. Furthermore, inhibition of MMP activity abolished this regional degradation. The integrity of the GCX altered EC morphological elongation to flow and leukocyte adhesion patterns. These results help strengthen the hypothesis that the EC GCX is involved in the mechanotransduction of hemodynamic forces and that the GCX is regulated by MMP activity in regions of WSSGs.
Collapse
|
35
|
Daughter Sac Formation Related to Blood Inflow Jet in an Intracranial Aneurysm. World Neurosurg 2016; 96:396-402. [DOI: 10.1016/j.wneu.2016.09.040] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2016] [Revised: 09/08/2016] [Accepted: 09/08/2016] [Indexed: 10/21/2022]
|
36
|
Li Y, Xiao W, Wu P, Deng Z, Zeng C, Li H, Yang T, Lei G. The expression of SIRT1 in articular cartilage of patients with knee osteoarthritis and its correlation with disease severity. J Orthop Surg Res 2016; 11:144. [PMID: 27863529 PMCID: PMC5116180 DOI: 10.1186/s13018-016-0477-8] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/27/2016] [Accepted: 11/04/2016] [Indexed: 11/29/2022] Open
Abstract
Background The study aims to investigate the expression of SIRT1 in articular cartilage of patients with primary knee osteoarthritis (OA) and its relationship with disease severity. Methods Cartilage tissue samples were collected from 38 knee OA patients and 9 normal healthy controls and then ascribed to normal, mild, moderate, and severe groups on the basis of the improved Mankin grading system. The expression of SIRT1 in articular cartilage was detected by immunohistochemistry and western blots. The expression of p53 and acetylated p53 (Ac-p53) was also measured by western blots. Results The mutual comparisons of the SIRT1 expression levels in all groups have statistical significance except the one between the mild and moderate groups. Moreover, western blot results showed that the SIRT1 was decreased and p53/Ac-p53 were increased in the OA group. The average gray level of SIRT1 increases with the improving grade of the improved Mankin grading system scorers. Conclusions The expression of SIRT1 in articular cartilage is negatively associated with severity of knee OA, indicating that SIRT1 may act as a monitoring indicator for determining development and progression of knee OA.
Collapse
Affiliation(s)
- Yusheng Li
- Department of Orthopaedics, Xiangya Hospital, Central South University, Changsha, Hunan Province, China
| | - Wenfeng Xiao
- Department of Orthopaedics, Xiangya Hospital, Central South University, Changsha, Hunan Province, China
| | - Ping Wu
- Department of Emergency Medicine, Xiangya Hospital, Central South University, Changsha, Hunan Province, China
| | - Zhenhan Deng
- Department of Orthopaedics, Xiangya Hospital, Central South University, Changsha, Hunan Province, China
| | - Chao Zeng
- Department of Orthopaedics, Xiangya Hospital, Central South University, Changsha, Hunan Province, China
| | - Hui Li
- Department of Orthopaedics, Xiangya Hospital, Central South University, Changsha, Hunan Province, China
| | - Tuo Yang
- Department of Orthopaedics, Xiangya Hospital, Central South University, Changsha, Hunan Province, China
| | - Guanghua Lei
- Department of Orthopaedics, Xiangya Hospital, Central South University, Changsha, Hunan Province, China.
| |
Collapse
|
37
|
Bourcier R, Lenoble C, Guyomarch-Delasalle B, Daumas-Duport B, Papagiannaki C, Redon R, Desal H. Is there an inherited anatomical conformation favoring aneurysmal formation of the anterior communicating artery? J Neurosurg 2016; 126:1598-1605. [PMID: 27315030 DOI: 10.3171/2016.4.jns153032] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
OBJECTIVE The pathophysiological mechanisms responsible for the formation of intracranial aneurysms (IAs) remain only partially elucidated. However, current evidence suggests a genetic component. The purpose of this study was to investigate the specific anatomical variations in the arterial complex that are associated with the presence of anterior communicating artery (ACoA) aneurysms in the familial forms of IAs. METHODS This multicenter study investigated bifurcation IAs in patients who had a sporadic ACoA IA without a family history of IA (SACAA group), in patients who had an ACoA IA with a family history of IA (FACAA group), and in their healthy first-degree relatives (HFDRs). Through the use of MR angiography (MRA) reconstructions, the symmetry of the A1 segments and the angle between the A1 and A2 segments were analyzed on 3D models for each group. These measurements were then compared among the 3 groups. RESULTS Twenty-four patients with SACAA, 24 patients with FACAA, and 20 HFDRs were included in the study. Asymmetrical configuration of the A1 segments was more frequent in the FACAA group than in the HFDR group (p = 0.002). The aneurysm-side A1-A2 angle was lower in the FACAA group (p = 0.003) and SACAA group (p = 0.007) than in the HFDR group. On the contralateral side, there was no difference in A1-A2 angles between groups. CONCLUSIONS The anatomical shape of the ACoA complex seems to be similarly associated with the presence of ACoA IAs in both the FACAA and SACAA groups. This highlights the role played by hemodynamic constraints in aneurysm formation and questions the hypothesis of the hereditary character of these anatomical shapes.
Collapse
Affiliation(s)
- Romain Bourcier
- Department of Diagnostic and Interventional Neuroradiology, Hospital Guillaume et René Laennec.,CNRS, UMR 6291, Université de Nantes, Nantes; and
| | - Cédric Lenoble
- Department of Diagnostic and Interventional Neuroradiology, Hospital Guillaume et René Laennec
| | | | - Benjamin Daumas-Duport
- Department of Diagnostic and Interventional Neuroradiology, Hospital Guillaume et René Laennec
| | | | - Richard Redon
- INSERM, UMR1087, l'institut du thorax, CHU de Nantes.,CNRS, UMR 6291, Université de Nantes, Nantes; and
| | - Hubert Desal
- Department of Diagnostic and Interventional Neuroradiology, Hospital Guillaume et René Laennec.,CNRS, UMR 6291, Université de Nantes, Nantes; and
| |
Collapse
|
38
|
Basic Principles of Hemodynamics and Cerebral Aneurysms. World Neurosurg 2016; 88:311-319. [DOI: 10.1016/j.wneu.2016.01.031] [Citation(s) in RCA: 44] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2015] [Revised: 01/03/2016] [Accepted: 01/05/2016] [Indexed: 11/18/2022]
|
39
|
Hasan DM, Hindman BJ, Todd MM. Pressure Changes Within the Sac of Human Cerebral Aneurysms in Response to Artificially Induced Transient Increases in Systemic Blood Pressure. Hypertension 2015; 66:324-31. [DOI: 10.1161/hypertensionaha.115.05500] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2015] [Accepted: 05/19/2015] [Indexed: 12/26/2022]
Abstract
Formation and rupture of cerebral aneurysms have been associated with chronic hypertension. The effect of transient increase in blood pressure and its effect on intra-aneurysmal hemodynamics have not been studied. We examined the effects of controlled increases in blood pressure on different pressure parameters inside the sac of human cerebral aneurysms and corresponding parent arteries using invasive technology. Twelve patients (10 female, 2 male, age 54±15 years) with unruptured cerebral aneurysms undergoing endovascular coiling were recruited. Dual-sensor microwires with the capacity to simultaneously measure flow velocity and pressure were used to measure systolic, diastolic, and mean pressure inside the aneurysm sac and to measure both pressures and flow velocities in the feeder vessel just outside the aneurysm. These pressures were recorded simultaneously with pressures from a radial arterial catheter. Measurements were taken at baseline and then during a gradual increase in systemic systolic blood pressure to a target value of ≈25 mm Hg above baseline, using a phenylephrine infusion. The dose needed to achieve the required increase in radial arterial systolic blood pressure was 0.8±0.2 μg/kg/min. There was a clear linear relationship between changes in radial and aneurysmal pressures with substantial patient-by-patient variation in the slopes of those relationships. The overall increases in systolic and mean pressures in both radial artery and in the aneurysms were similar. Pressures in the aneurysm and in the parent vessels were similar. Peak and mean flow velocities in the parent arteries did not change significantly with phenylephrine infusion, nor did vessel diameters as measured angiographically.
Collapse
Affiliation(s)
- David M. Hasan
- From the Department of Neurosurgery (D.M.H) and Department of Anesthesia (B.J.H., M.M.T.), University of Iowa Carver College of Medicine, Iowa City
| | - Bradley J. Hindman
- From the Department of Neurosurgery (D.M.H) and Department of Anesthesia (B.J.H., M.M.T.), University of Iowa Carver College of Medicine, Iowa City
| | - Michael M. Todd
- From the Department of Neurosurgery (D.M.H) and Department of Anesthesia (B.J.H., M.M.T.), University of Iowa Carver College of Medicine, Iowa City
| |
Collapse
|
40
|
Can A, Ho AL, Dammers R, Dirven CM, Du R. Morphological Parameters Associated With Middle Cerebral Artery Aneurysms. Neurosurgery 2015; 76:721-6; discussion 726-7. [DOI: 10.1227/neu.0000000000000713] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Abstract
BACKGROUND:
Morphological factors contribute to the hemodynamics of the middle cerebral artery (MCA).
OBJECTIVE:
To identify image-based morphological parameters that correlated with the presence of MCA aneurysms.
METHODS:
Image-based anatomic parameters obtained from 110 patients with and without MCA bifurcation aneurysms were evaluated with Slicer, an open-source image analysis software, to generate 3-dimensional models of the aneurysms and surrounding vascular architecture. We examined segment lengths, diameters, and vessel-to-vessel angles of the parent and daughter vessels at the MCA bifurcation. In order to reduce confounding by genetic and clinical risk factors, 2 control groups were selected: group A (the unaffected contralateral side of patients with unilateral MCA bifurcation aneurysms) and group B (patients without intracranial aneurysms or other vascular malformations). Univariate and multivariate analyses were performed to determine statistical significance.
RESULTS:
One hundred ten patients who were evaluated from 2007 to 2014 were analyzed (73 patients with MCA aneurysms and 37 control patients). Multivariate analysis revealed that a smaller parent artery diameter (group A: odds ratio [OR] 0.20, P < .01, group B: OR 0.23, P < .01) and a larger daughter-to-daughter branch angle (group A: OR 1.01, P = .04, group B: OR 1.02, P = .04) were most strongly associated with MCA aneurysm presence after adjusting for other morphological factors.
CONCLUSION:
Smaller parent artery diameter and larger daughter-to-daughter branch angles are associated with the presence of MCA bifurcation aneurysms. These easily measurable parameters may provide objective metrics to assess aneurysm formation and growth risk stratification in high-risk patients.
Collapse
Affiliation(s)
- Anil Can
- Department of Neurosurgery, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts
- Department of Neurosurgery, Erasmus Medical Center, Rotterdam, The Netherlands
| | - Allen L. Ho
- Department of Neurosurgery, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts
| | - Ruben Dammers
- Department of Neurosurgery, Erasmus Medical Center, Rotterdam, The Netherlands
| | - Clemens M.F. Dirven
- Department of Neurosurgery, Erasmus Medical Center, Rotterdam, The Netherlands
| | - Rose Du
- Department of Neurosurgery, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts
| |
Collapse
|
41
|
Tanweer O, Wilson TA, Metaxa E, Riina HA, Meng H. A comparative review of the hemodynamics and pathogenesis of cerebral and abdominal aortic aneurysms: lessons to learn from each other. J Cerebrovasc Endovasc Neurosurg 2014; 16:335-49. [PMID: 25599042 PMCID: PMC4296046 DOI: 10.7461/jcen.2014.16.4.335] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2014] [Revised: 10/13/2014] [Accepted: 10/29/2014] [Indexed: 12/28/2022] Open
Abstract
OBJECTIVE Cerebral aneurysms (CAs) and abdominal aortic aneurysms (AAAs) are degenerative vascular pathologies that manifest as abnormal dilations of the arterial wall. They arise with different morphologies in different types of blood vessels under different hemodynamic conditions. Although treated as different pathologies, we examine common pathways in their hemodynamic pathogenesis in order to elucidate mechanisms of formation. MATERIALS AND METHODS A systematic review of the literature was performed. Current concepts on pathogenesis and hemodynamics were collected and compared. RESULTS CAs arise as saccular dilations on the cerebral arteries of the circle of Willis under high blood flow, high wall shear stress (WSS), and high wall shear stress gradient (WSSG) conditions. AAAs arise as fusiform dilations on the infrarenal aorta under low blood flow, low, oscillating WSS, and high WSSG conditions. While at opposite ends of the WSS spectrum, they share high WSSG, a critical factor in arterial remodeling. This alone may not be enough to initiate aneurysm formation, but may ignite a cascade of downstream events that leads to aneurysm development. Despite differences in morphology and the structure, CAs and AAAs share many histopathological and biomechanical characteristics. Endothelial cell damage, loss of elastin, and smooth muscle cell loss are universal findings in CAs and AAAs. Increased matrix metalloproteinases and other proteinases, reactive oxygen species, and inflammation also contribute to the pathogenesis of both aneurysms. CONCLUSION Our review revealed similar pathways in seemingly different pathologies. We also highlight the need for cross-disciplinary studies to aid in finding similarities between pathologies.
Collapse
Affiliation(s)
- Omar Tanweer
- Department of Neurosurgery, New York University School of Medicine, NY, United States
| | - Taylor A Wilson
- Department of Neurosurgery, New York University School of Medicine, NY, United States
| | - Eleni Metaxa
- Foundation for Research and Technology - Hellas Institute of Applied and Computational Mathematics, Crete, Greece
| | - Howard A Riina
- Department of Neurosurgery, New York University School of Medicine, NY, United States
| | - Hui Meng
- Toshiba Stroke Research Center, University at Buffalo, NY, United States. ; Department of Mechanical and Aerospace Engineering, University at Buffalo, NY, United States. ; Department of Neurosurgery, University at Buffalo, NY, United States
| |
Collapse
|
42
|
Kono K, Fujimoto T, Terada T. Proximal stenosis may induce initiation of cerebral aneurysms by increasing wall shear stress and wall shear stress gradient. INTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN BIOMEDICAL ENGINEERING 2014; 30:942-950. [PMID: 24706583 DOI: 10.1002/cnm.2637] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/03/2013] [Revised: 02/02/2014] [Accepted: 03/10/2014] [Indexed: 06/03/2023]
Abstract
Hemodynamic parameters, such as wall shear stress (WSS), WSS gradient (WSSG), aneurysm formation indicator (AFI), or gradient oscillatory number (GON), have been proposed to be linked to initiation of cerebral aneurysms. However, how such conditions occur in humans is unclear. We encountered a rare and interesting case to address this issue. A patient had a newly formed aneurysm with proximal stenosis, which was confirmed by serial imagings. We made two pre-aneurysm models: one with stenosis and the other without stenosis. We performed computational fluid dynamics simulations for these models. Owing to jet flow caused by the stenosis, the maximum WSS and WSSG on the aneurysm initiation site were approximately doubled and tripled, respectively. However, the oscillatory shear index (OSI), AFI, and GON did not change substantially by the stenosis. Computer simulations using artificial vascular models with different degrees of proximal stenosis at different distances demonstrated that oscillatory shear index, AFI, and GON did not change substantially by the stenosis. These results showed that proximal stenosis caused high WSS and high WSSG at the aneurysm initiation site, possibly leading to aneurysm initiation. Proximal stenosis may be a potential factor to induce initiation of one class of cerebral aneurysms by increasing WSS and WSSG.
Collapse
Affiliation(s)
- Kenichi Kono
- Department of Neurosurgery, Wakayama Rosai Hospital, 93-1 Kinomoto, Wakayama 640-8505, Japan
| | | | | |
Collapse
|
43
|
Can A, Mouminah A, Ho AL, Du R. Effect of Vascular Anatomy on the Formation of Basilar Tip Aneurysms. Neurosurgery 2014; 76:62-6; discussion 66. [DOI: 10.1227/neu.0000000000000564] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
Abstract
BACKGROUND:
The pathogenesis of intracranial aneurysms is multifactorial and includes genetic, environmental, and anatomic influences. Hemodynamic stress plays a particular role in the formation of intracranial aneurysms, which is conditioned by the geometry and morphology of the vessel trees.
OBJECTIVE:
To identify image-based morphological parameters that correlated with the formation of basilar artery tip aneurysms (BTAs) in a location-specific manner.
METHODS:
Morphological parameters obtained from computed tomographic angiographies of 33 patients with BTAs and 33 patients with aneurysms at other locations were evaluated with Slicer, an open-source image analysis software, to generate 3-dimensional models of the aneurysms and surrounding vascular architecture. We examined the diameters and vessel-to-vessel angles of the main vessels at the basilar bifurcation in patients with and without BTAs. To control for genetic and other risk factors, only patients with at least 1 aneurysm were included. Univariate and multivariate analyses were performed to determine statistical significance.
RESULTS:
Sixty-six patients (33 with BTAs, 33 with other aneurysms) who were evaluated from 2008 to 2013 were analyzed. Multivariate logistic regression revealed that a larger angle between the posterior cerebral arteries (odds ratio, 1.04; P = 1.42 × 10−3) and a smaller basilar artery diameter (odds ratio, 0.23; P = .02) were most strongly associated with BTA formation after adjustment for other morphological and clinical variables.
CONCLUSION:
Larger posterior cerebral artery angles and smaller basilar artery diameters are associated with the formation of basilar tip aneurysms. These parameters are easily measurable by the clinician and will aid in screening strategies in high-risk patients.
Collapse
Affiliation(s)
- Anil Can
- Department of Neurosurgery, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts
| | - Amr Mouminah
- Department of Neurosurgery, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts
| | - Allen L. Ho
- Department of Neurosurgery, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts
| | - Rose Du
- Department of Neurosurgery, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts
| |
Collapse
|
44
|
Arterial Wall Degeneration Plus Hemodynamic Insult Cause Arterial Wall Remodeling and Nascent Aneurysm Formation at Specific Sites in Dogs. J Neuropathol Exp Neurol 2014; 73:808-19. [DOI: 10.1097/nen.0000000000000100] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
|
45
|
Lauric A, Hippelheuser J, Safain MG, Malek AM. Curvature effect on hemodynamic conditions at the inner bend of the carotid siphon and its relation to aneurysm formation. J Biomech 2014; 47:3018-27. [PMID: 25062932 DOI: 10.1016/j.jbiomech.2014.06.042] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2014] [Revised: 06/13/2014] [Accepted: 06/27/2014] [Indexed: 11/29/2022]
Abstract
Although high-impact hemodynamic forces are thought to lead to cerebral aneurysmal change, little is known about the aneurysm formation on the inner aspect of vascular bends such as the internal carotid artery (ICA) siphon where wall shear stress (WSS) is expected to be low. This study evaluates the effect of vessel curvature and hemodynamics on aneurysm formation along the inner carotid siphon. Catheter 3D-rotational angiographic volumes of 35 ICA (10 aneurysms, 25 controls) were evaluated in 3D for radius of curvature and peak curvature of the siphon bend, followed by univariate statistical analysis. Computational fluid dynamic (CFD) simulations were performed on patient-derived models after aneurysm removal and on synthetic variants of increasing curvature. Peak focal siphon curvature was significantly higher in aneurysm bearing ICAs (0.36 ± 0.045 vs. 0.30 ± 0.048 mm(-1), p=0.003), with no difference in global radius of curvature (p=0.36). In CFD simulations, increasing parametric curvature tightness (from 5 to 3mm radius) resulted in dramatic increase of WSS and WSS gradient magnitude (WSSG) on the inner wall of the bend. In patient-derived data, the location of aneurysms coincided with regions of low WSS (<4 Pa) flanked by high WSS and WSSG peaks. WSS peaks correlated with the aneurysm neck. In contrast, control siphon bends displayed low, almost constant, WSS and WSSG profiles with little spatial variation. High bend curvature induces dynamically fluctuating high proximal WSS and WSSG followed by regions of flow stasis and recirculation, leading to local conditions known to induce destructive vessel wall remodeling and aneurysmal initiation.
Collapse
Affiliation(s)
- Alexandra Lauric
- Cerebrovascular and Endovascular Division, Department of Neurosurgery, Tufts Medical Center, Tufts University School of Medicine, 800 Washington Street, Boston, MA 02111, USA
| | - James Hippelheuser
- Cerebrovascular and Endovascular Division, Department of Neurosurgery, Tufts Medical Center, Tufts University School of Medicine, 800 Washington Street, Boston, MA 02111, USA
| | - Mina G Safain
- Cerebrovascular and Endovascular Division, Department of Neurosurgery, Tufts Medical Center, Tufts University School of Medicine, 800 Washington Street, Boston, MA 02111, USA
| | - Adel M Malek
- Cerebrovascular and Endovascular Division, Department of Neurosurgery, Tufts Medical Center, Tufts University School of Medicine, 800 Washington Street, Boston, MA 02111, USA.
| |
Collapse
|
46
|
Endovascular coil embolization in internal carotid artery bifurcation aneurysms. Clin Radiol 2014; 69:e273-9. [DOI: 10.1016/j.crad.2014.01.017] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2013] [Revised: 01/13/2014] [Accepted: 01/16/2014] [Indexed: 02/07/2023]
|
47
|
Beneficial Remodeling of Small Saccular Intracranial Aneurysms after Staged Stent Only Treatment: A Case Series. J Stroke Cerebrovasc Dis 2014; 23:80-5. [DOI: 10.1016/j.jstrokecerebrovasdis.2012.09.012] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2012] [Revised: 07/10/2012] [Accepted: 09/19/2012] [Indexed: 02/08/2023] Open
|
48
|
Factors affecting formation and rupture of intracranial saccular aneurysms. Neurosurg Rev 2013; 37:1-14. [PMID: 24306170 DOI: 10.1007/s10143-013-0501-y] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2012] [Revised: 01/31/2013] [Accepted: 08/11/2013] [Indexed: 01/19/2023]
Abstract
Unruptured intracranial aneurysms represent a decisional challenge. Treatment risks have to be balanced against an unknown probability of rupture. A better understanding of the physiopathology is the basis for a better prediction of the natural history of an individual patient. Knowledge about the possible determining factors arises from a careful comparison between ruptured versus unruptured aneurysms and from the prospective observation and analysis of unbiased series with untreated, unruptured aneurysms. The key point is the correct identification of the determining variables for the fate of a specific aneurysm in a given individual. Thus, the increased knowledge of mechanisms of formation and eventual rupture of aneurysms should provide significant clues to the identification of rupture-prone aneurysms. Factors like structural vessel wall defects, local hemodynamic stress determined also by peculiar geometric configurations, and inflammation as trigger of a wall remodeling are crucial. In this sense the study of genetic modifiers of inflammatory responses together with the computational study of the vessel tree might contribute to identify aneurysms prone to rupture. The aim of this article is to underline the value of a unifying hypothesis that merges the role of geometry, with that of hemodynamics and of genetics as concerns vessel wall structure and inflammatory pathways.
Collapse
|
49
|
Kono K, Masuo O, Nakao N, Meng H. De Novo Cerebral Aneurysm Formation Associated With Proximal Stenosis. Neurosurgery 2013; 73:E1080-90. [DOI: 10.1227/neu.0000000000000065] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
|
50
|
Affiliation(s)
- Nohra Chalouhi
- From the Department of Neurosurgery, Thomas Jefferson University, Philadelphia, PA (N.C.); Jefferson Hospital for Neuroscience, Philadelphia, PA (N.C.); Department of Neurosurgery, University of Florida, Gainesville (B.L.H.); and Department of Neurosurgery, Carver College of Medicine, University of Iowa, Iowa City (D.H.)
| | | | | |
Collapse
|