Abstract
Vascular lesions of the brainstem are among the most complicated lesions treated by cerebrovascular neurosurgeons. Aneurysms, arteriovenous malformations, and cavernous malformations can be found in close association with all levels of the brainstem. Due to the inherent risk of treating brainstem pathologies, all surgical decision-making must first be predicated on knowledge of the natural history and radiographic appearance of these lesions. Successful microsurgical treatment of these lesions demands familiarity with an array of skull base approaches, which force surgeons to operate in deeper and narrower surgical corridors than with a corresponding supratentorial pathology. A regional understanding of the neurovascular anatomy that is unique to the midbrain, pons and medulla guides surgical planning. Advanced techniques are used when standard approaches cannot be performed safely, such as cerebral revascularization for complex aneurysms or in situ disconnection without pial dissection for arteriovenous malformations. With careful patient selection and dedication to developing the technical mastery necessary to operate in and around critical brainstem structures, vascular pathology of the brainstem can be treated safely.