Long-Term Rupture Risk in Patients with Unruptured Intracranial Aneurysms Treated with Endovascular Therapy: A...

Area of Science:

• Neurosurgery
• Interventional Radiology
• Vascular Neurology

Background:

• Routine surveillance imaging is common for previously unruptured, coiled aneurysms.
• Reports of rupture in these specific cases are exceptionally rare.

Purpose of the Study:

• To conduct a meta-analysis examining the long-term rupture risk of intracranial aneurysms after endovascular therapy.
• To assess rupture risk over follow-up durations of one year or more.

Main Methods:

• A meta-analysis was performed on studies published between 1995 and 2018.
• Included studies reported long-term rupture risk in patients with previously unruptured intracranial aneurysms treated endovascularly.
• Random effects meta-analysis calculated rupture rates per 100 patient-years with 95% confidence intervals (CIs).

Main Results:

• Analyzed 24 studies involving 4842 patients with a mean follow-up of 3.2 years.
• Twelve patients (0.25%) experienced aneurysm rupture post-treatment.
• Ruptures were predominantly associated with large, incompletely treated aneurysms; only 2 small, completely coiled aneurysms ruptured.
• The long-term rupture rate was 0.48 per 100 patient-years (95% CI, 0.45-0.51).
• Retreatment was necessary for 4.9% of patients.

Conclusions:

• Post-coil embolization rupture of well-treated, small- to medium-sized aneurysms is exceedingly rare.
• The findings suggest a low risk of spontaneous rupture in carefully selected and treated cases.