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

Asian J Neurosurg. Oct-Dec 2016;11(4):356-360. doi: 10.4103/1793-5482.180962.

Abstract

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.

Keywords: Computational flow dynamics; intraoperative microscopic findings; unruptured intracranial aneurysms; wall changes.