Parent Artery Occlusion Using Multiple Short iED Coils and n-Butyl Cyanoacrylate via a Marathon Microcatheter for a Dissecting Aneurysm of the Distal Posterior Inferior Cerebellar Artery With Severe Flexion of the Caudal Loop: A Case Report.

Dissecting aneurysms of the distal posterior inferior cerebellar artery (PICA) are relatively rare. This report discusses the use of multiple short iED coils via a Marathon microcatheter in a distal PICA dissecting aneurysm with severe flexion of the PICA caudal loop. A 58-year-old woman experienced a sudden, severe headache and sought consultation seven days after its onset. Head computed tomography (CT) revealed a slight left cerebellar hemorrhage. Cerebral angiography revealed a dissecting aneurysm in the telovelar tonsillar segment of the left distal PICA. Parent artery occlusion (PAO) via endovascular therapy was performed, aiming to implant coils. However, there was severe flexion of the PICA caudal loop, causing increased resistance during coil implantation, which led to the Marathon microcatheter deviating toward the basilar artery. Embolization of the dissecting aneurysm was achieved by carefully placing multiple short iED coils and administering 0.05 cc of 13% n-butyl cyanoacrylate (NBCA) via the Marathon microcatheter. Although the severe tortuosity of the PICA caudal loop made coil placement difficult, the extreme softness of the iED coil and flexibility of its delivery wire facilitated its successful placement. This case of dissecting aneurysm of the distal PICA with severe flexion of the caudal loop was successfully treated via PAO with multiple short iED coils and NBCA.