PREDICTORS OF ANEURYSMAL OCCLUSION IN THE PERIOD IMMEDIATELY AFTER ENDOVASCULAR TREATMENT WITH DETACHABLE COILS - A MULTIVARIATE-ANALYSIS

BACKGROUND AND PURPOSE: Complete intracranial aneurysmal occlusion by endovascular techniques is required for successful treatment and is pr esumably influenced by several parameters. The purpose of this study w as to investigate whether operator experience and angiographic charact eristics of intracranial aneurysms correspond to the degree of endovas cular occlusion in the period immediately after treatment with Gugliel mi detachable coils (GDCs). METHODS: Pre- and posttreatment angiograms of 72 patients undergoing GDC treatment were reviewed retrospectively . The following angiographic characteristics of the aneurysms were eva luated: largest diameter of the sac, volume, neck size, shape, type, c erebrovascular site, surroundings, and likely direction of aneurysmal inflow as judged by a score developed by measuring aneurysm/parent art ery angulation. The chronological sequence in which the aneurysms were treated nas used as a measure of operator experience, A chi(2)-test w as used to identify parameters that correlated,vith outcomes of total (100%) or partial (<100%) occlusion, A multivariate analysis was used to determine the factors most predictive of aneurysmal occlusion at th erapy. RESULTS: Parameters that correlated with the unsatisfactory res ult of partial occlusion were large aneurysmal diameter, volume, and n eck size, more direct inflow (ie, increasingly obtuse aneurysm/parent artery angulation), and early chronological presentation in the series . The three factors most predictive of partial occlusion were large an eurysmal diameter, more direct inflow, and early chronological order o f treatment. CONCLUSION: Several morphologic features of aneurysms wer e identified to help predict the immediate outcome of occlusion with G DCs, This study underscores the existence of a steep learning curve as sociated with GDC use in treating aneurysms and the importance of oper ator experience in achieving optimal therapeutic results.