Impact of the global outflow angle on recanalization after endovascular treatment of middle cerebral artery bifurcation aneurysms. (25th May 2018)

• Record Type: Journal Article
• Authors: de La Torre, Yannick; Velasco, Stéphane; Tasu, Jean-Pierre; Wanpouille, Cassandre; Chan, Paul; Velasco, Raphael; Sztark, Guillaume; Ingrand, Pierre; Boucebci, Samy
• Is Part Of: Journal of neurointerventional surgery. Volume 10:Number 12(2018)
• Page Start: 1174
• Page End: 1178
• Publication Date: 2018-05-25
• Subjects: aneurysm -- blood flow -- hemorrhage -- magnetic resonance angiography -- subarachnoid; Nervous system -- Surgery -- Periodicals; Cerebrovascular disease -- Surgery -- Periodicals; 617.48
• DOI: 10.1136/neurintsurg-2018-013803
• Languages: English
• ISSNs: 1759-8478

Abstract

Abstract : Background and purpose: Intracranial aneurysm recanalization after endovascular treatment (EVT) remains a major problem. The goal of this study was to find new predictive factors of recanalization after EVT of middle cerebral artery (MCA) bifurcation aneurysms. Methods: 96 MCA bifurcationaneurysms, ruptured or unruptured, treated by EVT between Septembre 2009 and December 2014, were retrospectively included. Clinical parameters and aneurysm characteristics were recorded. From the initial three-dimensional DSA, spatial coordinates found on parent and daughter arteries of MCA bifurcations gave four different flow angle values; inflow, outflows 1 and 2, and the global outflow angle (the sum of the two outflow angles). Inter- and intra-observer reproducibilities of three-dimensional angle value measurements were performed. Results: Recanalization occurred in 25 cases (26%) and retreatment was performed in 11 cases (11%). Only 1 patient (1%) had rebleeding. Univariate analysis established the following as predictive factors of recanalization: high blood pressure (P=0.014), aneurysm height (P<0.001), aneurysm width (P<0.001), neck size (P<0.001), postoperative occlusion class (P=0.040), percentage of packing volume (P<0.001), as well as the two outflow angles (P=0.006 and 0.045), and the global outflow angle (P<0.001). Multivariate analysis revealed two independent risk factors for recanalization: the global outflow angle (OR=1.05; 95% CI 1.02 to 1.08; P<0.002) and aneurysm width (OR=0.67; 95% CI 0.46 to 0.96; P=0.031). A global outflow angle threshold <192° was found to be a risk factor for recanalization (OR=13.75; 95% CI 4.46 to 42.44), with a sensitivity of 80% and specificity of 77%. Conclusions: This study emphasizes that a new parameter, the global outflow angle, can be predictive of recanalization for MCA bifurcation aneurysms treated by EVT.