Introduction: Intracranial atherosclerotic disease (ICAD) is one of the common causes of ischemic stroke worldwide. Notably, the risk of recurrent stroke is also higher in patients with ICAD, as compared to stroke due to other causes. It is therefore imperative to address and treat the underlying ICAD, in order to decrease the risk of subsequent transient ischemic attack (TIA) and strokes. Posterior circulation stroke and stenosis is associated with 2.5-15% stroke risk per year and 33% in the first month after symptoms are noticed in some studies with best medical management.

Methods: Out of the total 154 eligible abstracts and full-length papers, 67 studies met our inclusion criteria and the data from these studies were included in our meta-analysis. A total of 599 subjects and 611 lesions were identified that underwent angioplasty for the treatment of posterior circulation ICAD.

Results: This data of available literature suggests that angioplasty for symptomatic ICAD may be able to dilate the vessel and achieve technical success (defined as <50% stenosis) in approximately 74% of cases. The rate of peri-procedural complications was defined as the occurrence of dissection, vasospasm, TIA, stroke, hemorrhage or death within 30-days of the procedure. The rate of peri-procedural complications is 26% in our results, a significant portion can be attributed to dissection of the vessel (9%). Angioplasty techniques and devices have drastically changed over the years, with some studies showing the technical success rates over 90% and 30-day major complication rates below 6%.

Conclusions: Submaximal angioplasty, providing higher success rates and lower peri-procedural complication rates, may be considered the next step for these patients to prevent recurrent ischemic complications. Further randomized trials are needed for better assessment of this procedure in patients with posterior circulation ICAD.

Patient Care: It opens up discussion for sub maximal angioplasty for posterior circulation ICAD.

Learning Objectives: - the natural history of posterior circulation ICAD - the problems with treatment of posterior circulation ICAD - the benefits of angioplasty and possible future directions

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