脳動静脈奇形の臨床病理学的検討—とくにEVAL（ethylene vinyl alcohol copolymer）塞栓術後摘出例について

Clinicopathological Evaluation of EVAL (ethylene vinyl alcohol copolymer) Embolization in AVMs

I．はじめに

　脳動静脈奇形（AVM）の根治的な治療は，原則的にはnidusを全摘出することであるが，外科的治療には種々の限界がある．近年手術を容易にするため術前AVMの塞栓術が行われ注目されている^{1,8,12,16,20,21）}。私共も，液性塞栓物質（EVAL）を用いて塞栓術を施行している．今回本法実施後全摘出したAVM 2例の手術所見，病理学的所見より，EVAL塞栓術の問題点について検討を加えた．

The clinical and pathological aspects of two large arteriovenous malformations which were removed total-ly after preoperative embolization using ethylene vinyl alcohol copolymer (EVAL) were studied. The material, which is not adhesive, is handled easily during the pro-cedure of embolization. However, it involves some risks because it might migrate to and occlude the normal branches of the brain and pass through the nidus to the venous system. Histopathological study of AVM nidus which was removed showed embolic materials within the vessels and inflammatory reaction of the vessel wall and its surrounding tissue. There were patchy hemor-rhages within the AVM nidus and its surrounding brain tissue. Recanalization was also found within the occluded vessels. These findings suggest that preopera-tive embolization has some risk of causing intracerebral hemorrhage after the embolization. AVM should be re-moved surgically as a radical treatment if the patient is able to tolerate the operation.