Staged Treatment of High Flow, Large Cerebral Arteriovenous Malformation with a Combination of Preoperative Embolization and Microsurgery

Surgical treatment of cerebral arteriovenous malformations(AVM's) that are high flow and large remain particularly difficult to manage. It has been reported that normal perfusion pressure breakthrough(NPPB) syndrome occur more frequently in such AVM's and managing such AVM's by staged treatment may help to avoid the occurrence of this complication. The authors report our experience with one case of high flow, large AVM that would pose a great operative difficulty if it was to be managed by surgical resection alone. The patient was treated by a staged procedure in which a preoperative embolization was followed by a complete microsurgical excision. The staged, complementary approach proved to be quite useful and safe for the treatment of high flow, large AVM.

Successful Management of Large Cerebral Arteriovenous Malformation by Preoperative Embolization and One-stage Operation

The surgery of large cerebral arteriovenous malformation(AVM) may be complicated by the potential for serious brain swelling and hemorrhage during operation and/or postoperative period due to "normal perfusion pressure breadthrough(NPPB)". The authors present two cases of successful management of large AVM which anticipated the development of 'NPPB' using hypotension and preoperative embolization. The one case admitted with intraventricular hemorrhage and intracerebral hematoma due to rupture of large occipital AVM. We managed him with one-stage resection, followed by postoperative hypotension successfully. The another case was interesting. He had the history of intracranial hemorrhage about 13 years ago. We treated him conservatively at that time. He also had the another attack of intracranial hemorrhage in 1979. We performed angiography which revealed large AVM around trigon of left lateral ventricle. He also had another one time of intracranial hemorrhage in 1985. In 1986, We decided to treat him surgically and repeated angiography which showed enlarged AVM compare to size of AVM in previous angiogram of 1979 definitely. We embolized this lesion with Ivalon(R)(polyvinyl alcohol) and confirmed decreased size of AVM. During waiting the surgical resection, another intracranial hemorrhage occurred and recovered without surgical management. In May 1987, we decided to do operation and performed preoperative angiography, which showed reenlarged of previous embolic obliterated AVM. We resected that AVM successfully and discharged him without any aggravation of previous neurological signs. The pathologic findings of resected embolized AVM revealed infiltration of neurtrophils within vessel walls and foreign body material, surrounded by multinucleated foreign body giant cells, epitheloid cells in the vessel lumen. We reviewed the literature and discussed the enlargement of AVM, the treatment of large AVM, especially in point of view about 'NPPB' and pathologic findings of embolized AVM with Ivalon(R)(polyvinyl alcohol).