後頭蓋窩病変術後のDisproportionately Large Communicating Fourth Ventricle

A Disproportionately Large Communicating Fourth Ventricle Occurring after Suboccipital Craniectorny: Report of two cases

I．はじめに

　Disproportionately large communicating fourth ven—tricle（DLCFV）は，第四脳室が側脳室や第三脳室と比較して，不均衡に拡大した水頭症のうち，中脳水道に閉塞を認めないものとして報告されている^1）．この病態は，通常，側脳室腹腔短絡術（V-P shunt）により改善すると言われている^1-3）．私達は，最近後頭蓋窩病変の術後に，第四脳室の不均衡な拡大を示した2症例を経験した．側脳室より造影剤を注入した脳室撮影では，中脳水道は開存しており，DLCFVの診断のもとにV-P shuntを行ったが，第四脳室の縮小は得られなかった．これらの2症例を呈示し，若干の考察を加え報告する．

Abstract

Two cases of a disproportionately large communicat-ing fourth ventricle (DLCFV) which developed after suboccipital craniectomy are reported.

The first case was that of a 43-year-old female who sustained subarachnoid hemorrhage, and the second case was that of a 12-year-old male with medullohlasto-ma. Patency of the ageductal canal and occlusion of the fourth ventricle outlets were demonstrated in both cases by metrizamide ventriculography, with in-traventricular injection of contrast material.

Clinical history was analyzed with repeated CT scan, and pathogenesis of DI.C.FV was discussed with review of the literature.