Is 3 years adequate for tracking completely occluded coiled aneurysms?

Area of Science:

• Neurosurgery
• Interventional Radiology
• Vascular Neurology

Background:

• Delayed recanalization of coiled aneurysms is a potential complication.
• Long-term durability data for completely occluded aneurysms is crucial for clinical decision-making.

Purpose of the Study:

• To evaluate the long-term durability of intracranial aneurysms that achieved complete occlusion at 36 months post-coiling.
• To determine the incidence and risk factors for delayed recanalization in this patient cohort.

Main Methods:

• Retrospective review of 339 coiled aneurysms in 299 patients with complete occlusion at 36 months.
• Analysis of extended follow-up data (mean 74.3 months) for delayed recanalization incidence and risk factors.

Main Results:

• Only 5 aneurysms (1.5%) showed delayed recanalization (0.46% per aneurysm-year) during extended surveillance.
• One instance of major recanalization occurred, unrelated to coil compaction, in a posterior communicating artery aneurysm.
• A second embolization for a recurrent aneurysm independently correlated with delayed recanalization (HR = 22.088, p = 0.003).

Conclusions:

• Coiled aneurysms achieving complete occlusion at 36 months demonstrate high long-term stability (98.5%).
• Recurrent aneurysms are predisposed to delayed recanalization.
• Continued, albeit less frequent, monitoring may be considered beyond 36 months due to the low risk of recanalization and de novo aneurysm formation.