RT Journal Article SR Electronic T1 Onset-to-treatment time and aneurysmal regression predict improvement of cranial neuropathy after flow diversion treatment in patients with symptomatic internal carotid artery aneurysms JF Journal of NeuroInterventional Surgery JO J NeuroIntervent Surg FD BMJ Publishing Group Ltd. SP neurintsurg-2022-019202 DO 10.1136/jnis-2022-019202 A1 Ryo Akiyama A1 Akira Ishii A1 Takayuki Kikuchi A1 Masakazu Okawa A1 Yukihiro Yamao A1 Yu Abekura A1 Isao Ono A1 Natsuhi Sasaki A1 Hirofumi Tsuji A1 Hirotoshi Imamura A1 Taketo Hatano A1 Nobuyuki Sakai A1 Susumu Miyamoto YR 2022 UL http://jnis.bmj.com/content/early/2022/07/19/jnis-2022-019202.abstract AB Background Although flow diversion plays a pivotal role in treating internal carotid artery aneurysms presenting with cranial neuropathy, predictors of symptom improvement have not been established.Objective To investigate improvement of symptoms after flow diversion treatment in patients with internal carotid artery aneurysms causing cranial neuropathy, with sufficient follow-up period. Additionally, to examine factors associated with improvement of symptoms.Methods This retrospective multicenter study examined patients with unruptured internal carotid artery aneurysms presenting with cranial neuropathy who were treated using flow diversion and followed up for at least 12 months. Study outcomes were transient worsening of symptoms and symptom status 12 months after treatment. Patient and aneurysm characteristics were statistically analyzed.Results Seventy-seven patients were included. Data needed for outcome analysis were available for 66 patients. At the 1-, 3-, 6-, 12-month, and last follow-ups, the proportion of patients with resolved or improved symptoms was 26% (20/77), 51% (39/77), 74% (57/77), 83% (64/77), and 79%(62/77), respectively. Symptom onset-to-treatment time <6 months (OR=24.2; 95% CI 3.09 to 188.84; p=0.002) and aneurysmal regression (OR=23.1; 95% CI 1.97 to 271.75; p=0.012) were significantly associated with symptom improvement. Transient symptom worsening and worse symptoms at 12 months occurred in 19/77 (25%) and 2/77 (3%) patients, respectively.Conclusions The rate of cranial neuropathy symptom improvement after flow diversion increased over the first 12 months after treatment, but not thereafter. Treatment within 6 months of symptom onset and aneurysmal regression were predictors of symptom improvement.Data are available upon reasonable request. Any additional data regarding this submission can be requested from the corresponding author via email.