Early postoperative angiography after clipping of intracranial aneurysms : clinical value of angiography and predisposing factors for aneurysm remnants

Abstract

Aneurysm remnants after microsurgical clipping have a risk of regrowth and rupture and have not been validated in the era of 3-dimensional angiography. Although computed tomography angiography (CTA) is currently preferred for evaluating aneurysmal clipping results, it cannot completely rule out postoperative remnant occurrence. Furthermore, there is no concrete evidence supporting its superior accuracy to digital subtraction angiography (DSA). Therefore, this study aimed to (1) evaluate the clinical value of angiography in diagnosing remnants, (2) determine the rate of remnants, and (3) identify the predictors for remnants after microsurgical clipping. Between January 2014 and May 2017, 200 aneurysms in 154 patients, treated via microsurgical clipping, were considered eligible for the present study. Among them, 139 aneurysms in 106 patients were finally selected for evaluation. The results of microsurgical clipping were evaluated within 7 days to predict the remnant development risk using DSA based on the classification, and clinical features of the patients and characteristics of treated aneurysms. The rate of aneurysm remnants, including intentional remnants, was 29.5%, and retreatments were needed in 6.5% of such cases. Neck size (cut-off: 5.68 mm; sensitivity, 66.7%; specificity, 96.2%) and maximum diameter (cut-off: 7.03 mm; sensitivity, 66.7%; specificity, 89.2%) of aneurysms were independent predisposing factors for the occurrence of aneurysm remnants that need retreatment (OR: 2.30; p < 0.001; OR: 1.38; p < 0.001, respectively). Postoperative DSA may identify remnants after microsurgical clipping. Aneurysms with larger neck size and maximum diameter have a higher risk of aneurysmal remnants after clipping.

뇌동맥류 결찰 후 발생하는 잔여 뇌동맥류는 재성장과 파열의 위험성이 있으나, 이에 대한 3차원 뇌혈관조영술을 이용한 검증은 제대로 이루어지지 않았다. 본 연구에서는 3차원 뇌혈관조영술을 이용하여 결찰 후 발생하는 잔여 뇌동맥류의 위험인자를 분석하여 뇌혈관조영술의 임상적 의미에 대해 고찰해보고자 한다. 뇌동맥류 결찰을 시행한 후 2주 이내 뇌혈관조영술을 시행한 환자들을 대상으로 하였으며, 환자들의 특성 및 치료한 뇌동맥류의 특성 그리고 수술 후 시행한 3차원 뇌혈관조영술을 토대로한 잔여 뇌동맥류를 분석하였다. 총 106명 환자의 139개의 뇌동맥류를 대상으로 분석하였고, 41개의 뇌동맥류가 잔여 뇌동맥류로 확인되었다. (29.5%) 통계적인 분석을 통해 뇌동맥류의 목 길이 (승산비 2.30)와 최대 직경(승산비 1.38)이 뇌동맥류 결찰 후 치료가 필요한 뇌동맥류 발생의 독립적인 예측인자임을 확인하였다. 본 연구를 통해 뇌동맥류 결찰 후 초기 시행한 혈관조영술이 잔여 뇌동맥류를 진단하는데 유용함을 확인하였으며, 수술 전 뇌동맥류의 목 길이와 최대 직경이 재치료가 필요한 잔여 뇌동맥류 발생의 예측인자임을 알 수 있다.