A fifty-five-year-old woman with a history of migraine suddenly develo
ped an occipital headache and visual disturbance after a typical migra
inous attack. On admission, she had a left homonymous hemianopsia, and
computed tomography of the brain demonstrated intracranial hematomas
in the occipital subcortices bilaterally. Cerebral arteriography revea
led diffuse vasospasm of the intracranial arteries attributed to the m
igraine. The cystatin C concentration in the cerebrospinal fluid was l
ow, which suggested the existence of cerebral amyloid angiopathy. Acco
rding to the clinical course and angiographic findings, it is suggeste
d that the vasospasm associated with migraine played an important role
in developing multiple brain hemorrhage in this patient.