[Dejerine-Roussy syndrome following endovascular parent artery occlusion for an unruptured posterior cerebral artery aneurysm (P2 segment): case report].

A right posterior cerebral artery (PCA) fusiform aneurysm was incidentally discovered in a 53-year-old man. Although the aneurysm was asymptomatic, treatment of the aneurysm was indicated to avoid possible hemorrhage and/or mass effect. Since the patient tolerated temporary balloon occlusion of the right PCA at P1-P2 segments and sufficient collateral flow to the right temporo-occipital region was observed during such occlusion, parent artery occlusion as well as intraluminal occlusion of the aneurysm was performed with Guglielmi detachable coils. The patient did not develop neurological deficit immediately after embolization. However, he subsequently developed Dejerine-Roussy syndrome due to an infarction in the territory of the thalamogeniculate artery. Parent artery occlusion together with intraluminal aneurysmal obliteration is an useful treatment for a fusiform aneurysm of the PCA. However, ischemic complication in the territory of the perforating artery can not be predicted.