Comparison of Bypass and Non-Bypass Surgical Treatments for Internal Carotid Artery Blood Blister-Like Aneurysms: A Meta-Analysis of Efficacy, Safety, and Outcomes.

BACKGROUND: The optimal surgical strategy for treating internal carotid artery (ICA) blood blister-like aneurysms (BBAs) has remained unclear. Although some have preferred bypass surgery, others have favored less-demanding surgical methods. The aim of the present meta-analysis was to assess the efficacy, safety, and outcomes of bypass and non-bypass surgical methods when intended as primary treatment of ICA BBAs. METHODS: Studies reporting data on the outcomes of interest for surgically treated patients with ICA BBAs were searched for in the PubMed/MEDLINE, Evidence-Based Medicine Reviews, Cochrane Central, ProQuest, and Scopus databases. The data were analyzed using random effects modeling. RESULTS: Seven observational studies involving 140 patients met the inclusion criteria. The patients treated with bypass surgery, compared with those treated with non-bypass techniques, had lower odds of poor outcomes (odds ratio [OR], 0.75; 95% confidence interval [CI], 0.28-2.02; P = 0.57; I2 = 0%), postoperative vasospasm (OR, 1.73; 95% CI, 0.38-7.92; P = 0.48; I2 = 19%), intraoperative bleeding (OR, 3.37; 95% CI, 0.82-13.90; P = 0.09; I2 = 0%), postoperative bleeding (OR, 1.91; 95% CI, 0.47-7.76; P = 0.36; I2 = 0%), and postoperative recurrence of BBAs (OR, 2.16; 95% CI, 0.54-8.66; P < 0.28; I2 = 0%). No comparison, however, achieved statistical significance. CONCLUSIONS: For surgeons who use both bypass and non-bypass surgical strategies, the 2 methods seemed comparable in terms of the outcomes of interest, although the bypass technique appeared superior. However, comparisons with studies reporting bypass as the uniquely preferred technique have indicated that specialization in, and preference for, the bypass procedure has been associated with more favorable outcomes.

Unilateral Fenestrated A1 Segment of Anterior Cerebral Artery Multiple Aneurysms: Case Reports and Literature Review.

The fenestration of the cerebral arteries is infrequent anomaly mostly occurring in the posterior communicating artery, the vertebral artery, the basilar artery, and the middle cerebral artery.[1] We report a case of unilateral A1 fenestration associated saccular aneurysm, focusing on its features of surgical treatment.

Computational Fluid Dynamics Analysis and Correlation with Intraoperative Aneurysm Features.

INTRODUCTION: There are many controversies about computational fluid dynamics (CFD) findings and aneurysm initiation, growth, and ultimate rupture. The aim of our work was to analyze CFD data in a consecutive series of patients and to correlate them with intraoperative visual aneurysm findings. METHODS: Hemoscope software (Amin, Ziosoft Corporation, Minato ward, Tokyo, Japan) was used to process images from 17 patients who underwent clipping of 18 aneurysms. Pressure (P), wall shear stress (WSS) gradient and vectors, normalized WSS, and streamlines (SL) direction and velocity were assessed. CFD data were compared to intraoperative visual findings. A total of 39 aneurysm wall areas were assessed. RESULTS: Red, thin aneurysm wall areas were more often associated with low WSS. However, the association of low WSS with high P, diverging WSS vectors, direct impact of SL, and high SL velocity more frequently matched with yellow, atherosclerotic aneurysm walls. CONCLUSIONS: Low WSS alone is not sufficient to determine the thickness of an aneurysm wall. Its association with other parameters might enable one to distinguish preoperatively atherosclerotic, thick areas (high P, diverging WSS vectors, high flow velocity) from thin areas with higher rupture risk (parallel WSS vectors, lower flow velocity). The changing balance between these parameters can modify the features and the risk of rupture of aneurysm wall over time.

State-of-art in surgical treatment of dissecting posterior circulation intracranial aneurysms.

Vertebrobasilar (VB) intracranial dissecting aneurysms (IDAs) pose difficult therapeutic issues and are especially among the most difficult to manage surgically. There are, however, some cases where selective aneurysm obliteration by endovascular approach is impossible or is associated with an unacceptable risk of morbidity. This is particularly true when the aneurysm is dissecting, giant, or has a large neck. In such cases, surgical treatment may be the only alternative. Optimal management of these lesions is therefore challenging and treatment decisions have to be made on a case-by-case basis. Ideal treatment should be a complete surgical excision of the lesion; however, this procedure might only be possible after distal and proximal vessel wall occlusion which might not be tolerated by the patient depending on the location of the aneurysm. Therefore, formulation of recommendations concerning the surgical strategy remains still difficult due to inconsistency of surgical outcomes. The literature describing surgical strategy of VB IDAs is varying in quality and content, and many studies deal with only a few patients. In the presented review, the authors summarize the current knowledge on the incidence, pathogenesis, clinical presentation, and diagnostic procedures with special emphasis on surgical treatment of IDAs in posterior circulation.

State-of-Art Surgical Treatment of Dissecting Anterior Circulation Intracranial Aneurysms.

Intracranial dissecting aneurysms (IDAs) are an important cause of subarachnoid hemorrhage, stroke, or compression of intracranial structures. Since the availability of endovascular treatment and the advantage of intraprocedural anticoagulation, an endovascular strategy has become the mainstay of their therapy. But in some cases selective aneurysm obliteration by the endovascular approach is impossible or associated with an unacceptable risk of morbidity. This is particularly true when the IDA is a blood blister-like aneurysm or when dissection affects peripheral branches of the internal carotid artery. The literature dealing with surgical treatment of IDAs in the anterior circulation is heterogeneous, and formulation of general recommendations concerning the surgical strategy remains difficult. The aim of this study was to conduct a systematic review of the current knowledge on incidence, pathogenesis, clinical presentation, and diagnostic procedures with a special emphasis on the surgical treatment of intracranial dissections of anterior circulation.

Surgical treatment of unruptured dissecting intracranial aneurysms of vertebral-posterior inferior cerebellar artery region.

A lack of published surgical experience and higher symptomatic recurrence than previously recognized prompted the authors to present their experience with the surgical treatment of unruptured intracranial dissecting aneurysms (UIDAs). Hospital records, neuroimaging studies, operative reports, and follow-up records were retrospectively reviewed. All patients underwent surgical exploration of the lesion with proximal clipping of the parent artery through a far-lateral suboccipital craniotomy with or without partial condylar resection. The surgical treatment of vertebral artery-posterior inferior cerebellar artery UIDAs has acceptable risk regarding perioperative mortality and morbidity. The incidence of aneurysmal recurrence or the need for retreatment seems to be less than that associated with anticoagulation/antiplatelet therapy or endovascular treatment.

Comparison of computational fluid dynamics findings with intraoperative microscopy findings in unruptured intracranial aneurysms- An initial analysis.

CONTEXT: The increase in the detection of unruptured cerebral aneurysms has led to management dilemma. Prediction of risk based on the size of the aneurysm is not always accurate. There is no objective way of predicting rupture of aneurysm so far. Computational fluid dynamics (CFDs) was proposed as a tool to identify the rupture risk. AIMS: To know the correlation of CFD findings with intraoperative microscopic findings and to know the relevance of CFD in the prediction of rupture risk and in the management of unruptured intracranial aneurysms. SETTINGS AND DESIGN: A prospective study involving nine cases over a period of 6 months as an initial analysis. SUBJECTS AND METHODS: Both males and females were included in the study. Preoperative analysis was performed using computed tomography angiogram, magnetic resonance imaging in all cases and digital substraction angiogram in some cases. Intraoperatively microscopic examination of the aneurysm wall was carried out and images recorded. The correlation was done between microscopic and CFD images. RESULTS: Seven cases were found intraoperatively to have a higher risk of rupture based on the thinning of the wall. Two cases had an atherosclerotic wall. All cases had low wall shear stress (WSS).Only two cases with atherosclerotic wall had a correlation with low WSS. CONCLUSIONS: While the pressure measured with CFD technique is a good predictor of rupture risk, the WSS component is controversial. Multicentric trials involving a larger subset of population are needed before drawing any definite conclusions. On-going development in the CFD analysis may help to predict the rupture chances accurately in future.