抄録
The authors present the fifth reported case of arteriovenous malformation (AVM) associated with cyst formation. Among these five cases, computed tomography has demonstrated two types of cyst: round, and slit-like with low density. The three patients with slit-like cysts experienced sudden, severe headache, probably due to hemorrhage. The two patients with round cystic lesions did not have sudden headache, and at surgery the cysts were found to contain a mural nodule. These facts suggest that there may be two different mechanisms of cyst formation in the vicinity of an AVM: hemorrhage (slit-like cysts) and exudation (round cysts).
