UPmémoires

English

Impact of morphological factors in the recanalization of anterior communicating artery aneurysms treated by endovascular approach

Background and purpose : This study sought to identify morphological factors influencing recanalization aneurysms of the anterior communicating artery after endovascular treatment.

Methods : A retrospective study was conducted of 156 aneurysms of the anterior communicating artery treated by an endovascular approach between January 2006 and December 2013. Epidemiological data were gathered as well as morphological parameters (height, width, size of neck, height/width ratio, ASPECT ratio, and dominance of segment A1). New parameters were calculated : a) the global outflow angle which is the sum of the angles between the afferent artery and both efferent arteries of the aneurysm ; b) the inflow angle. Univariate and multivariate analyses of all of these parameters were performed.

Results : 130 aneurysms were ruptured and 26 unruptured at the time of diagnosis. Mean follow-up was 34 months and the average time of recanalization was 21.5 months. Univariate analysis retained as recanalization factors : height (p = 0.03), size of neck (p < 0.0001), aneurysmal width (p = 0.0008), ASPECT ratio (p = 0.007), dominance of one segment A1 (p = 0.007) and global outflow angle (p <0.0001). The multivariate analysis established three factors of recanalization : the global outflow angle (OR 0.97; 95 % CI, 0.96 to 0.98), height (OR 1.39; 95 % CI, 1, 1 to 1.7) and ASPECT ratio (OR 0.27; 95 % CI, 0.14 to 0.5).

Conclusion : We have identified a new morphological factor of recanalization aneurysms in the anterior communicating artery: the global outflow angle. This factor should be taken into account when planning the embolization of unruptured aneurysms in order to anticipate the need for intracranial stents.

Keywords : intracranial aneurysm, recanalization, risk factors.