Hemispheric divided coiling technique for coil embolization of middle- and large-sized intracranial aneurysms.

Despite major developments in treating intracranial aneurysms by endovascular coil embolization, complete occlusion of the entire aneurysmal neck remains a problem. We present a novel endovascular strategy for middle- and large sized aneurysms called the "hemispheric divided coiling technique" and compare the short-term follow-up results of this technique with those of conventional coil embolization. Ten patients (mean age, 69.7 ± 9.7 years) with middle- or large-sized ruptured or unruptured intracranial aneurysms (mean maximum aneurysmal diameter, 12.09 ± 3.6 mm) were treated by the hemispheric divided coiling technique, in combination with various adjunctive techniques. We compared the initial occlusion grade, volume embolization ratio, and recurrence rate in this group of patients (hemispheric group) with the results from 20 previous cases (conventional group: mean age, 62.8 ± 9.8 years; mean maximum aneurysmal diameter, 11.43 ± 3.5 mm). The mean volume embolization ratio of the hemispheric group was significantly higher than that of the conventional group (42.3% vs. 31.1%). The hemispheric divided coiling technique achieved a high volume embolization ratio for middle- and large sized intracranial aneurysms, with a low recurrence rate.