Risk Factor Analysis of Recanalization Timing in Coiled Aneurysms: Early versus Late Recanalization

• Published in: American journal of neuroradiology : AJNR Vol. 38; no. 9; pp. 1765 - 1770
• Main Authors: Jeon, J P, Cho, Y D, Yoo, D H, Moon, J, Lee, J, Cho, W-S, Kang, H-S, Kim, J E, Han, M H
• Format: Journal Article
• Language: English
• Published: United States American Society of Neuroradiology 01-09-2017
• Subjects: Adult; Aged; Aneurysm; Aneurysms; Coiling; Electrocardiography; Embolization, Therapeutic - methods; Endovascular coiling; Endovascular Procedures - methods; Factor analysis; Female; Hemorrhage; Humans; Interventional; Intracranial Aneurysm - pathology; Intracranial Aneurysm - surgery; Lesions; Male; Medical records; Middle Aged; Occlusion; Recurrence; Regression analysis; Regression models; Retrospective Studies; Risk analysis; Risk Factors; Saccule; Subarachnoid hemorrhage; Treatment Outcome
• ISSN: 0195-6108; 1936-959X
• DOI: 10.3174/ajnr.a5267

Long-term documentation of anatomic and angiographic characteristics pertaining to the timing of recanalization in coiled aneurysms has been insufficient. Our intent was to analyze and compare early and late-phase recanalization after coiling, identifying respective risk factors.
A total of 870 coiled saccular aneurysms were monitored for extended periods (mean, 30.8 ± 8.3 months). Medical records and radiologic data were also reviewed, stratifying patients as either early (
= 128) or late (
= 52) recanalization or as complete occlusion (
= 690). Early recanalization was equated with confirmed recanalization within 6 months after the procedure, whereas late recanalization was defined as verifiable recanalization after imaging confirmation of complete occlusion at 6 months. A multinomial regression model served to assess potential risk factors, the reference point being early recanalization.
Posterior circulation (
= .009), subarachnoid hemorrhage at presentation (
= .011), second attempt for recanalized aneurysm (
< .001), and aneurysm size >7 mm (
< .001) emerged as variables significantly linked with early recanalization (versus complete occlusion). Late (versus early) recanalization corresponded with aneurysms ≤7 mm (
= .013), and in a separate subanalysis of lesions ≤7 mm, aneurysms 4-7 mm showed a significant predilection for late recanalization (
= .008). However, the propensity for complete occlusion in smaller lesions (≤7 mm) increased as the size diminished.
Although long-term complete occlusion after coiling was more likely in aneurysms ≤7 mm, such lesions were more prone to late (versus early) recanalization, particularly those of 4-7 mm in size. Long-term follow-up imaging is thus appropriate in aneurysms >4 mm to detect late recanalization of those formerly demonstrating complete occlusion.