Cavernoma of the septum pellucidum in the region of foramen of Monro.

A rare case of cavernoma in the region of the septum pellucidum is reported. A 35-year-old female patient presented with chronic headaches. Her neurological exam was normal. Her magnetic resonance (MR) imaging showed a lesion within the inferior aspect of the septum pellucidum extending into the anterior third ventricular region, blocking the foramen of Monro, resulting in moderate supratentorial asymmetrical hydrocephalus. A central neurocytoma or subependymoma was suspected on imaging. Complete excision of the septum pellucidum cavernoma was performed using microneurosurgical techniques through an interhemispheric transcallosal route. The patient had an excellent outcome and is cured. Although rare, septum pellucidum cavernomas should be considered in the differential diagnosis of anterior third ventricular lesions in the region of foramen of Monro. The unusual location, atypical radiological features, differential diagnosis as well as surgical nuances in the management of a cavernoma in the septum pellucidum and anterior third ventricular region are discussed in the light of current literature.