[A case of frontal arteriovenous malformation with optochiasmatic arachnoiditis as an initial symptoms (author's transl)].

A surgically cured case of chronic optochiasmal arachnoiditis presumably caused by concomitant right frontal arteriovenous malformation (AVM) is reported. When a 12-year-old boy, suffering from blurred vision for about 1 month, visited the Ophthalmological Clinic of Hirosaki University Hospital, only a chiasmal lesion was suspected because neuro-ophthalmological examination revealed no more than ophthalmic signs, such as bilateral diminution of vision (Vd, Vs = 0.2), concentric narrowing of visual fields and slight bilateral papilledema. The patient was referred to the Neurosurgical clinic for further examination. Left carotid angiograms showed no abnormalities but, thereafter the brain scintigram revealed an abnormal hot area in the right frontoparietal region. A right carotid angiography demonstreated an AVM in the posterior part of the right frontal lobe. This was fed through the right anterior and middle cerebral arteries and drained into the superior sagittal sinus through meandering dilated cortical vein.