Reduced Efficacy of the Pipeline Embolization Device in the Treatment of Posterior Communicating Region Aneurysms with Fetal Posterior Cerebral Artery Configuration.

BACKGROUND: Aneurysms at the origin of the posterior communicating artery (PcommA) have been demonstrated to be effectively treated with the pipeline embolization device (PED). Much less is known about the efficacy of the PED for aneurysms associated with a fetal posterior cerebral artery (fPCA) variant.
OBJECTIVE: To study PED treatment efficacy of PcommA aneurysms, including fPCA aneurysms.
METHODS: A prospectively maintained university database of aneurysm patients treated with the PED was retrospectively reviewed. Demographics, treatment details, and imaging were reviewed for all PcommA and fPCA aneurysms.
RESULTS: Out of a total of 285 patients treated with PED, 50 patients (mean age 57.5 ± 12.2 yr, 42 females) with unruptured PcommA (9 fPCA) aneurysms were identified. Mean follow-up duration was 14.0 ± 11.6 mo (48 patients). Roy-Raymond class I occlusion on follow-up magnetic resonance or catheter angiography (mean time 11.7 ± 6.8 mo) was achieved in 30 patients (62.5%), class II occlusion in 11 patients (22.9%) and class III occlusion in 7 patients (14.5%). The PcommA was occluded in 56% of patients without any clinical symptoms. No deaths or permanent neurological complications occurred. In fPCA aneurysms, class I occlusion was seen in 1 patient, class 2 occlusion in 2 patients, and class III occlusion in 6 patients. Multivariate analysis revealed an independent association between incomplete occlusion and fPCA configuration (OR 73.65; 95% CI: 5.84-929.13; P = .001).
CONCLUSION: The PED is a safe and effective treatment for PcommA aneurysms, although fetal anatomy should increase consideration of traditional endovascular techniques or surgical clipping.