Venous ThrombosisにMedullary Venous Malformationを合併した1例

A Case of Venous Thrombosis Associated with Medullary Venous Malformation

I．はじめに

　頭蓋内静脈還流の障害，異常により生じるvenousthrombosisおよびmedullary venous malformation（MVM）は，それぞれ単独では希ならず遭遇する疾患であるが，合併して認めることはほとんどない．今回われわれは頭蓋内のvenous thrombosisで発症し，病状の極期にMVMを合併した1症例を経験した．症例を提示し，MVMの病態像を中心に考察を加え報告する．

A 16 year-old girl was admitted to our hospital com-plaining of headache and vomiting. She was born with an orbital lymphangioma, which was resected partially at a younger age. On admission she had mild confusion and light neck stiffness as neurological positive find-ings. Enhanced CT scan showed an eight-figure en-hancement at the straight sinus and a linear enhance-ment at the vermis. Angiography showed venous thrombosis spreading in the deep cerebral veins and the right superior ophthalmic vein. Furthermore a medul-lary venous malformation (MVM) was disclosed in the posterior fossa. Administration of urokinase and glycerol relieved her symptoms gradually. After that treatment, partial recanalization of the deep cerebral veins and the straight sinus and disappearance of the MVM were recognized in the second angiography. In the present case, the MVM played an important role as collateral channel. But, in general, when venous throm-bosis occurs, collateral circulation is maintained by cork-screw vessels, not by MVM. In the light of the presence of the lymphangioma, the present case was thought to be a rare condition in the venous system. It appears that residual fetal vessels have existed in the posterior fossa from birth. It is considered that the re-sidual fetal vessels opened and dilated temporally and were recognized as an MVM in angiography, when cerebral venous flow was disturbed by the venous thrombosis.