scholarly journals Threshold Values of Morphological Parameters Associated with Cerebral Aneurysm Rupture Risk

2019 ◽  
Vol 19 (3) ◽  
pp. 289-304
Author(s):  
Aleksandr V. Dol ◽  
◽  
Olga A. Fomkina ◽  
Dmitriy V. Ivanov ◽  
◽  
...  
Keyword(s):  
Cerebral Aneurysm ◽  
Aneurysm Rupture ◽  
Morphological Parameters ◽  
Rupture Risk ◽  
Threshold Values

Abstract 1122‐000015: Differences of Morphological and Hemodynamic Rupture Risk Factors in Cerebral Aneurysms Between Pre‐ and Post‐Rupture

2021 ◽  
Vol 1 (S1) ◽  
Author(s):  
Yuma Yamanaka ◽  
Hiroyuki Takao ◽  
Soichiro Fujimura ◽  
Yuya Uchiyama ◽  
Shota Sunami ◽  
...  
Keyword(s):  
Risk Factors ◽  
Blood Flow ◽  
Shear Stress ◽  
Wall Shear Stress ◽  
Cerebral Aneurysms ◽  
Aneurysm Rupture ◽  
Morphological Parameters ◽  
Rupture Risk ◽  
Parent Vessel ◽  
Cfd Simulations

Introduction : Morphological and hemodynamic characteristics have been reported to be involved in the rupture of cerebral aneurysms. Therefore, geometrical measurements of cerebral aneurysms and blood flow analysis using computational fluid dynamics (CFD) have been conducted. Some previous studies investigated the rupture risk factors from cerebral arterial geometries that were taken before the rupture (pre‐rupture), and the others used geometries taken after the rupture (post‐rupture). However, aneurysm rupture may alter arterial geometries and CFD simulation results. The aim of this study is to evaluate the morphological and hemodynamic alternations due to cerebral aneurysm rupture. Methods : We identified 21 cerebral aneurysms (ICA: 9, MCA: 3, ACA: 4, BA: 3, VA: 2) which had ruptured during the follow‐up terms. Each case had at longest two‐years term between the rupture date and the latest angiographic date before the aneurysm rupture (pre‐rupture). The post‐rupture arterial geometries were acquired preoperatively for subarachnoid hemorrhage. We used the arterial geometries reconstructed from computed tomography angiography or digital subtraction angiography images for conducting morphological measurements and CFD simulations. We performed transient blood flow simulations for two heart pulse cycles in the CFD simulations. We obtained five morphological parameters and 24 hemodynamic parameters considered as the rupture risk factors. Finally, we conducted Wilcoxon’s signed‐rank sum test between the parameters obtained from pre‐ and post‐rupture aneurysms to specify altered parameters due to the aneurysm rupture. We also calculated the change rate (CR) based on the value in pre‐rupture for parameters that had a statistical significance to investigate the alternation in detail. Results : The aneurysmal volume ( V ), height ( H ), aspect ratio ( AR ), and spatial averaged, maximum, and minimum wall shear stress of the aneurysm dome normalized by the spatially averaged wall shear stress of the parent vessel ( NWSSave , NWSSmax , and NWSSmin ) were significantly altered between pre‐ and post‐rupture. In particular, the morphological parameters increased after the rupture (average CR of V , H , and AR were 25.8 %, 13.4 %, and 15.9 %, respectively). These results indicate that the aneurysm shapes tended to increase lengthwise after the rupture. On the other hand, the NWSS tended to decrease (average CR of NWSSave , NWSSmax , and NWSSmin  were ‐21.0 %, ‐13.7 %, and ‐22.7 %, respectively). These results imply that the aneurysm rupture altered the aneurysm to a more complicated shape, and thereby the blood flow became stagnated that introduced lower WSS . In contrast, there were some cases in which NWSS increased, and these cases had vasospasm at their parent arteries caused by the rupture (i.e., 5 of 21 cases had vasospasm, and the average CR of NWSSave was 14.1 %). The parent vessel proximal to the aneurysm was shrunk due to the vasospasm, resulting in increased flow velocity and thus increased NWSS . Conclusions : The cerebral aneurysm rupture deformed the aneurysms into longitudinal and led to increased volumes. The NWSSs in CFD simulations using post‐rupture geometries tended to decrease in comparison with pre‐rupture. When studying rupture factors of cerebral aneurysms using geometrical measurements and CFD simulations, special attention should be paid to the clinical image and rupture characteristics standardization criteria.

Abstract TP77: Simple Morphological Parameters Associated With The Rupture Risk Of Posterior Communicating Artery Aneurysms.

Stroke ◽  
2013 ◽  
Vol 44 (suppl_1) ◽  
Author(s):  
Allen Ho ◽  
Ning Lin ◽  
Mary Stanley ◽  
Nareerat Charoenvimolphan ◽  
Sarthak Misra ◽  
...  
Keyword(s):  
Aspect Ratio ◽  
Statistical Significance ◽  
Morphological Characteristics ◽  
Aneurysm Rupture ◽  
Size Ratio ◽  
Morphological Parameters ◽  
Rupture Risk ◽  
Flow Angle ◽  
Aneurysm Neck ◽  
Neck Diameter

Introduction: The contribution of morphological characteristics to the treatment decision of unruptured aneurysms has not been established in a systematic and location specific manner. We present a large sample of posterior communicating (PComm) aneurysms that were assessed using a diverse array of morphological variables to determine the parameters associated with aneurysm rupture. Methods: Demographic and clinical risk factors of aneurysm rupture were obtained viachart review. Pre-operative CT angiograms (CTA) were evaluated with 3D Slicer© to generate 3-D models of the aneurysms and surrounding vascular architecture. Morphological parameters examined in each model included aneurysm volume, aspect ratio, size ratio, distance to bifurcation and origin points, aneurysm angle, vessel angles, flow angles, and parent-daughter angles. Univariate and multivariate analyses were performed to determine statistical significance. Results: From 2005-2011, 141 PComm aneurysms were treated in a single institution, and preoperative CTAs from 48 patients (32 ruptured, 16 unruptured) were analyzed. Those that underwent reoperation, were associated with arteriovenous malformations, or lacked a preoperative CTA were excluded. Ruptured aneurysms were associated with smaller volume, greater aspect ratio, greater size ratio, smaller internal carotid artery (ICA) to aneurysm neck angle, larger PComm flow angle, larger ICA to PComm angle, and smaller PComm to daughter vessel angle. Multivariate logistic regression revealed that a larger neck diameter, greater aspect ratio, greater size ratio, and shorter ICA bifurcation to aneurysm distance were the most strongly associated with rupture after adjusting for all other variables. Interestingly, volume of the aneurysm had a smaller effect size than most other variables and rupture risk was associated with smaller volumes. Conclusion: We found that larger neck diameter, greater aspect ratio, greater size ratio, and smaller ICA bifurcation to aneurysm distance to be highly associated with PComm aneurysm rupture. These are easily measured and physically intuitive parameters. They are more strongly associated with PComm aneurysm rupture than size alone and can be readily applied in clinical practice.

Type I Endoleaks: Is Aneurysm Rupture Risk Dependent on the Presence of Type II Endoleaks?

2002 ◽  
Vol 9 (5) ◽  
pp. 707-709 ◽  
Author(s):  
Stéphan Haulon ◽  
Serge Willoteaux ◽  
Mohamad Koussa ◽  
Pascal Halna ◽  
Jean-Paul Beregi
Keyword(s):  
Aneurysm Rupture ◽  
Type I ◽  
Type Ii ◽  
Rupture Risk

scholarly journals Morphological variables associated with ruptured basilar tip aneurysms

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Jian Zhang ◽  
Anil Can ◽  
Pui Man Rosalind Lai ◽  
Srinivasan Mukundan ◽  
Victor M. Castro ◽  
...  
Keyword(s):  
Statistical Significance ◽  
Multivariable Analysis ◽  
Aneurysm Rupture ◽  
Size Ratio ◽  
Width Ratio ◽  
Maximum Height ◽  
Morphological Parameters ◽  
Flow Angle ◽  
Aneurysm Wall ◽  
Fisher Grade

AbstractMorphological factors of intracranial aneurysms and the surrounding vasculature could affect aneurysm rupture risk in a location specific manner. Our goal was to identify image-based morphological parameters that correlated with ruptured basilar tip aneurysms. Three-dimensional morphological parameters obtained from CT-angiography (CTA) or digital subtraction angiography (DSA) from 200 patients with basilar tip aneurysms diagnosed at the Brigham and Women’s Hospital and Massachusetts General Hospital between 1990 and 2016 were evaluated. We examined aneurysm wall irregularity, the presence of daughter domes, hypoplastic, aplastic or fetal PCoAs, vertebral dominance, maximum height, perpendicular height, width, neck diameter, aspect and size ratio, height/width ratio, and diameters and angles of surrounding parent and daughter vessels. Univariable and multivariable statistical analyses were performed to determine statistical significance. In multivariable analysis, presence of a daughter dome, aspect ratio, and larger flow angle were significantly associated with rupture status. We also introduced two new variables, diameter size ratio and parent-daughter angle ratio, which were both significantly inversely associated with ruptured basilar tip aneurysms. Notably, multivariable analyses also showed that larger diameter size ratio was associated with higher Hunt-Hess score while smaller flow angle was associated with higher Fisher grade. These easily measurable parameters, including a new parameter that is unlikely to be affected by the formation of the aneurysm, could aid in screening strategies in high-risk patients with basilar tip aneurysms. One should note, however, that the changes in parameters related to aneurysm morphology may be secondary to aneurysm rupture rather than causal.

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