Background Posterior communicating artery (PcoA) compromise may serve as adjunctive treatment in patients with hypoplastic variants of PcoA who undergo coil embolization of PcoA aneurysms. However, procedural safety and the propensity for later recanalization are still unclear.

Objective To evaluate clinical and radiologic outcomes of coil embolization in this setting, focusing on compromise of PcoA.

Methods As a retrospective review, we examined 250 patients harboring 291 aneurysms of hypoplastic PcoAs, all consecutively treated by coil embolization between January 2004 and June 2016. PcoA compromise was undertaken in conjunction with 81 of the treated aneurysms (27.8%; incomplete 53; complete 28). Medical records and radiologic data were assessed during extended monitoring.

Results During the mean follow-up of 33.9±24.6 months (median 36 months), a total of 107 (36.8%) coiled aneurysms showed recanalization (minor 50; major 57). Recanalization rates were as follows: PcoA preservation 40.5% (85/210); incomplete PcoA occlusion 34.0% (18/53); complete PcoA occlusion 14.3% (4/28). Aneurysms >7 mm (HR 3.40; P<0.01), retreatment for recanalization (HR 3.23; P<0.01), and compromise of PcoA (P<0.01) emerged from multivariate analysis as significant risk factors for recanalization. Compared with PcoA preservation, complete PcoA compromise conferred more favorable outcomes (HR 0.160), whereas incomplete compromise of PcoA fell short of statistical significance. Thromboembolic infarction related to PcoA compromise did not occur in any patient.

Conclusion PcoA compromise in conjunction with coil embolization of PcoA aneurysms appears safe in hypoplastic variants of PcoA, helping to prevent recanalization if complete occlusion is achieved.