Surgical management of cavernous malformations of the brainstem

Cavernomas are well circumscribed lesions formed by sinusoidal vascular channels. They tend to slowly expand in size and carry a 0.7% to 1.1% annual risk of hemorrhage. Only 10% to 30% of intracranial cavernomas are located in the posterior fossa. When located in the brainstem they can cause recurrent hemorrhages and devastating neurological deficits. The authors report a series of cavernomas located in the brainstem and present a review on their epidemiology, pathogenesis, natural history, and methods of diagnosis and treatment. Although the surgical treatment of brainstem cavernomas can be associated with a significant risk, surgical resection is recommended of the lesions that have hemorrhaged or grown producing progressive deficits. The authors' experience on the surgical treatment of cavernous hemangiomas of the brainstem, indicating important aspects of intra-operative surgical techniques, is presented, including a clinical and anatomical correlation of different surgical approaches to brainstem cavernomas.