Chronic encapsulated intracerebral hematoma: a rare complication after stereotactic radiosurgery for cerebral arteriovenous malformation

Abstract

We read with great interest the article entitled “Operative intervention for delayed symptomatic radionecrotic masses developing following stereotactic radiosurgery for cerebral arteriovenous malformations-case analysis and literature review” by Foroughi et al. [1] in the May 2010 issue of this journal. The authors presented two cases of delayed masses that had developed following stereotactic radiosurgery (SRS) for the treatment of cerebral arteriovenous malformations (AVMs) and discussed the relevant literature. They pointed out that some cases had presented with hemorrhage in the cystic cavity. We would like to add a comment regarding this point. Chronic encapsulated intracerebral hematoma (CEIH) is a rare cerebrovascular disease that behaves as a slowly expanding lesion with a gradual onset [2]. We previously reported a case of delayed CEIH that developed after SRS for a cerebral AVM, which was treated by a single aspiration following the placement of a reservoir [3]. Furthermore, we experienced a similar case of a delayed mass that developed after SRS for an AVM. This patient underwent surgical excision and was diagnosed as CEIH by a pathological method. We suppose that SRS for an AVM can cause the formation of CEIH. Based on our experiences, it is suggested that some delayed masses with hemorrhage after SRS for an AVM may be CEIH.