Endovascular Treatment of Isolated Posterior Inferior Cerebellar Artery Dissecting Aneurysms: Parent Artery Occlusion or Selective Coiling?

Isolated posterior inferior cerebellar artery dissecting aneurysms are rare lesions. Their underlying pathology, presentation, and natural history are poorly understood. Their treatment is controversial, and few data are available regarding the best treatment. We conducted the first study comparing selective coiling and parent artery occlusion for the treatment of isolated PICA dissecting aneurysms. All patients harboring isolated PICA dissecting aneurysms treated between January 2006 and October 2012, in a single center, were retrospectively evaluated. Patients were consecutively submitted either to selective coiling or parent artery occlusion. The safety and durability (recanalization and rebleeding rates) of each treatment were established. In order to compare the results of both treatment modalities, we also performed a literature search of all cases of isolated PICA dissecting aneurysms endovascularly treated. Fourteen patients harboring isolated PICA dissecting aneurysms were assigned to endovascular treatment in our center (eight to selective coiling vs six to parent artery occlusion). There was no statistical difference between both groups regarding complications. No patient experienced rebleeding. One recanalization was observed in the selective coiling group. Based on literature review (83 cases), selective coiling and parent artery occlusion showed similar success rate in preventing rebleeding. Parent artery occlusion was significantly associated with a higher risk of ischemic complication (p = 0.013). Both selective coiling and parent artery occlusion are highly effective in preventing rebleeding in isolated PICA dissecting aneurysms. Although total complication rate is similar between both modalities, parent artery occlusion is significantly associated to a higher risk of ischemic events.