第四脳室内出血で発症した中小脳脚AVMの1例

抄録

We present the case of a 74-year-old woman with middle cerebellar peduncular AVM (Spetzler-Martin grade II) resulting in fourth ventricular hemorrhage. CT scans revealed fourth ventricular hemorrhage complicated with small hematoma in the right middle cerebellar peduncle. MRI demonstrated that the right middle cerebellar peduncle showed high signal intensity in T2-weighted and FLAIR images. Vertebral angiogram revealed the nidus of AVM supplied by the right superior cerebellar artery (SCA) and anterior inferior cerebellar artery (AICA) and draining in the right superior petrous sinus (SPS) with a varix.
Gamma knife radiosurgery was performed. A maximum dose of 50 Gy was delivered with a marginal dose of 25 Gy. We considered two hypotheses for why AVM located in the middle cerebellar peduncle has caused fourth ventricular hemorrhage. One is that the hemorrhage of the right middle cerebellar peduncle perforated into the fourth ventricle. The other is that a rupture of vein of lateral recess of fourth ventricle (VLR) caused by retrograde venous hypertension resulted in fourth ventricular hemorrhage.