Reported is a case 〔} f a 44 − year − old nlan who developed an intracerebral hematonla of the right temporal lobe. Angiography failed to reveal any vascular abnormalities except f 〔 〕 r the presence of the mass . The hematoma was cvac し lated through a cranio 亡 omy , at which tjme many small vessels were llotecl in the surro し mdillg white matter and the wall of the hematonla. 「 llhese vesse ] s c ( )lmected to the subependymal veins of the inferior horn of the right lateral ventricle ,

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... gically , these vessels had smooth vascular muscles without interna !elastic lamillae . indicating venous cha [ mels , Thus , based on these findings , the vascular lesjon " ・ as diagnosed as being a medullary venous malforma − tion 、 In thc diagnosis of a medullary venous malformation , it must be kept in mind that allgiography does not always visualize the radiological findings . Therefore , the inlportance of the 〔) perati 、 ・ e findings and careful macro − and micro scopic examiilatiolls of the resected specimen are stressed , (