Research of postoperative complications after coil protrusions in embolization of unruptured cerebral aneurysms

Objectives: Postoperative courses in "coil-protruded" cases in embolization of unruptured cerebral aneurysms remain unknown. The purpose of this study is to investigate postoperative complications after coil protrusions. Methods: From May 2003 to December 2007, 90 consecutive cases with unruptured cerebral aneurysm treated by coil embolization were examined at National Cerebral and Cardiovascular Center. All patients received antiplatelet therapy prior to the procedure. The patterns of protrusions were classified into three; tail (T), loop (L), unraveled (U). Results: Coil protrusions were observed in 17 cases (18.9%). Symptomatic ischemic complications occurred in 7 cases (7.8%). One case occurred in coil protrusions (group P) and 6 cases occurred in no coil protrusions (group N). Infarctions on MR diffusion-weighted image within 7 days after embolization were found in 10 cases (58.8%) in group P and in 28 cases (38.4%) in group N. Infarction on MR fluid attenuated inversion recovery 7 days or later were found in 0 in group P, and in 4 (5.5%) in group N. There were no significant differences. The number of each protrusion pattern was as follows: T was 12 cases, L was 3 cases and U was 2 cases. Symptomatic ischemia was observed in one case (8.3%) in T. Infarctions on MR diffusion-weighted image within 7 days after embolization were found in 7 (58.3%), 1 (33.3%) and 2 (100%), respectively. There were no significant differences between the three morphological patterns. Conclusion: In this retrospective study, coil protrusion after embolization of unruptured cerebral aneurysms on antiplatelet therapy, did not increase the incidence of ischemic complications.