内視鏡的第三脳室開窓術の理論と実際

Theory and Practice of Endoscopic Third Ventriculostomy

Point

・内視鏡的第三脳室開窓術（ETV）は髄液拍動のエネルギーをくも膜下腔に伝え，脳室壁を介して脳実質に与えていた拍動の負荷を軽減させる．

・稀ではあるが脳底動脈を損傷した際は，脳圧制御下に洗浄して止血を待つのが肝要である．

・ETVは閉塞し得るので術後フォローが必要である．

　Endoscopic third ventriculostomy（ETV）is a basic procedure for the surgical treatment of hydrocephalus. It buffers pulsatile pressure by creating an alternative route for the flow of cerebrospinal fluid and reduces trans-mantle pulsatile stress, thereby increasing compliance of the brain parenchyma. Blunt perforation of the third ventricular floor is done while avoiding injury to the foramen of Monro, the hypothalamus, the pituitary stalk, and some cisternal vessels. A major complication of ETV is arterial bleeding caused by injury to the basilar artery. Surgeons should wait with irrigation and opening the root into the ventricle to control the intra-ventricular pressure until packing the third ventricle with hematoma. Since ETV may close by gliosis or scarring of the inter-peduncular cistern, regular physical examinations and MRI should follow the procedure.