LAUSR

BACKGROUND Intraventricular meningiomas comprise 0.5%-3% of intracranial meningiomas. They often cause obstructive hydrocephalus and commonly are treated with surgical resection or stereotactic radiosurgery. OBJECTIVE To describe the surgical approaches and resection techniques needed to approach intraventricular tumors while highlighting the eloquent anatomy and blood supply surrounding the ventricular system to avoid neurological injury. METHODS Two cases of left atrial intraventricular meningiomas that were complicated by postoperative lateral geniculate nucleus ischemia and resultant temporary contralateral quadrantanopia are described. The safe surgical approaches to the atrium of lateral ventricles as well as the anatomy and blood supply to the lateral geniculate nucleus and optic radiation are discussed and illustrated. RESULTS In both cases, the patients had complete resection of their tumors. They both ultimately made a good recovery after transient visual deficits. These cases provide useful demonstrations of eloquent anatomy of the ventricular walls and visual pathway anatomy. CONCLUSIONS Care must be taken to avoid visual pathways along the lateral ventricle wall and the nearby arterial supply of the lateral geniculate nucleus from the choroidal arteries when resecting intraventricular tumors.