正常圧水頭症の症状を呈した脳底動脈尖端部未破裂巨大動脈瘤

Occult Hydrocephalus due to Unruptured Giant Basilar Bifurcation Aneurysm

I．はじめに

　1964年Hakimが成人における水頭症で髄液圧が正常な症候群を記載し，1965年Adamsらによって正常圧水頭症（Normal Pressure Hydrocephalus）（以下，NPHと略す）の概念が提唱され，以後，本疾患に関して多くの報告がみられる．

　NPHの発生には，原因不明な一次性のものと，くも膜下出血，頭部外傷などの明らかな原因疾患がみられる二次性のものとがある．

A case is presented in which a syndrome of occult hydrocephalus was manifested with an unruptured giant aneurysm at the bifurcation of the basilar artery.

This is a 52-year-old male who was admitted with de-mentia. He had been in good health until seven months previously when he was noted to have impairment of memory for recent events. Two months later he deve-loped tremor in both arms, predominantly on the left, accompanied by weakness of the left leg. At about that time, he was noted to have difficulty in walking and urinary incontinence. General physical examination on admission was unremarkable.