Abstract
A case of hydrocephalus due to MDBA is reported. A 66 year-old man complained of dementia and gait disturbances for 6 months. Brain CT revealed hydrocephalus, while cerebral angiography indicated MDBA. Dynamic studies of the CSF presented no abnormality as to passage through the subarachnoid space, absorption and pressure. Hydrocephalus due to MDBA was therefore diagnosed. T2-weighted MRI demonstrated an elongated basilar artery as low intensity signals due to high-velocity signal loss in the high intensity area of the subarachnoid space, which elevated the basis of the III-rd ventricle resulting in deformity. Furthermore, MRI demonstrated not only the dilated lateral ventricles with the thin corpus callosum, but also the dilated IV-th ventricle and aqueduct. The latter findings suggested that one of the mechanisms of the dilatation process was voluminal changes due to pulse-synchronous translocation of the III-rd ventricular basis rather than a water-hammering effect causing dilatation of the IV-th ventricle and aqueduct.
