Incidence and Characteristics of Remote Intracerebral Hemorrhage After Endovascular Treatment of Unruptured Intracranial Aneurysms.

Objective: The purpose of this study was to investigate the incidence and characteristics of remote intracerebral hemorrhage (ICH) after endovascular treatment (EVT) of unruptured intracranial aneurysms (UIAs).

Methods: Between March 2007 and September 2015, 11 patients with remote ICH from a series of 2258 consecutive patients with 2597 UIAs treated via EVT were identified. Baseline demographic characteristics, medical history, radiologic imaging data, characteristics of remote ICH, and clinical outcomes were retrospectively reviewed. The characteristics of patients with remote ICH were compared with those of patients without remote ICH.

Results: All hematomas were single lesions located in the subcortical white matter as lobar-type in 9 patients (81.8%) and in the basal ganglia in 2 patients (18.2%). Events occurred mostly within 1 week and up to 3 weeks after EVT. Hematoma was located on the ipsilateral side in 8 patients (72.7%) and in the contralateral side in 3 patients (27.3%). Compared with patients without remote ICH, there were more aneurysms located on the internal carotid artery (ICA) (P = 0.041), more patients treated with stents (P < 0.001), more patients with hypertension (P = 0.026), and poorer clinical outcomes at discharge (P < 0.001) for patients with remote ICH.

Conclusions: The incidence of remote ICH after EVT of UIAs was 0.46%. This event occurred mostly in patients with stents, hypertension, and UIAs on the ICA. It presented mostly as an ipsilateral lobar-type hemorrhage within 1 week after the procedure. This complication should not be neglected because of its poor clinical outcomes.