P102 Endovascular treatment in precommunicating segment aneurysms of posterior cerebral artery

<h3>Introduction</h3> Precommunicating (P1) segment aneurysms of the posterior cerebral artery are rare, with few studies reported to date. <h3>Aim of Study</h3> Herein, we address the clinical and radiologic outcomes of their endovascular treatment. <h3>Methods</h3> For this study, we retrieved prospectively collected data on 35 consecutive patients with 37 P1 aneurysms, analyzing the clinical ramifications and morphologic outcomes of treatment. All subjects received endovascular interventions between January 2001 and October 2021. <h3>Results</h3> There were 16 aneurysms (43.2%) of P1 segment sidewalls and 21 (56.8%) at P1/posterior communicating artery junctions. Five (13.5%) were fusiform, and 14 (37.8%) were ruptured. In 14 patients (40%), 16 aneurysms (43%) were associated with intracranial arterial occlusive disease of the anterior circulation. Selective coiling was undertaken in 34 aneurysms (91.9%), using single (n = 24) or double (n = 4) microcatheters, microcatheter protection (n = 2), or stents (n = 4); and trapping was done in 3 (8.1%). No procedure-related morbidity or mortality resulted. Excluding the trapped lesions, angiographic follow-up of 29 aneurysms obtained &gt;6 months after embolization (mean, 12.4 month) revealed stable occlusion in 21 (72.4%), with some recanalization in the other 8 (minor: 3/29, 10.4%; major: 5/29, 17.2%). <h3>Conclusion</h3> Aneurysms of P1 segment (vs. other locations) are strongly associated with intracranial arterial occlusive disease of the anterior circulation and thus are likely flow related. Endovascular treatment of such lesions seems safe and efficacious, despite the array of technical strategies that their distinctive anatomic configurations impose. <h3>Disclosure of Interest</h3> no.