2018 年 46 巻 3 号 p. 177-183
Flow diverters have been introduced as a novel treatment modality for large to giant cerebral aneurysms. To obtain baseline data for comparison, we analyzed a series of patients who underwent traditional surgical or conservative treatment.
We retrospectively studied 48 patients with large to giant cerebral aneurysms (≥15 mm in size) treated in our institute between 2007 and 2016. Ages ranged from 24 to 81 years (average, 65 years). Among the 11 men and 35 women in the study, 8 had aneurysms at the C3-C5 segment of the internal carotid artery (ICA: according to Fischer's classification), 10 at the C2 segment, and 14 at the C1 segment; 5 had aneurysms at the middle cerebral artery; and 11 had aneurysms in the posterior circulation. Twenty-nine aneurysms were symptomatic (13 were hemorrhagic and 16 presented with mass signs) and 19 were asymptomatic. Cases were retrospectively analyzed according to treatment modality and outcomes, and the natural history was evaluated in cases in which patients did not undergo surgery for more than a year.
Nine of 13 aneurysms that did not undergo surgery when first discovered became symptomatic and/or enlarged and were subsequently treated surgically. Final treatment methods were as follows: conservative treatment in 6, external obliteration (aneurysm clipping or trapping, followed by thrombectomy) in 19, internal obliteration (aneurysm packed with coils) in 5, and flow alteration with or without bypass in 16, of which 3 were performed with external obliteration and 3 with internal obliteration. Outcomes in patients with ICA aneurysms at the C3-5 and C2 segments were favorable (modified Rankin Scale [mRS] score 0 to 2) in 17 of 18 (94%). On the other hand, 11 of 19 patients (58%) with aneurysms at C1 of the ICA or middle cerebral artery experienced favorable outcomes. In the remaining cases, cerebral ischemia including perforating artery involvement led to worse outcomes. Only 2 (18%) of 11 patients with posterior circulation aneurysms had favorable outcomes. Aneurysms that were initially managed conservatively enlarged by an average of 3.5 mm per year.
Treatment outcomes with use of flow diverters for complex cerebral aneurysms may yield results that are comparable or superior to those of traditional treatment.
