Hemorrhagic cavum vergae colloid cyst: A presentation of anterograde amnesia without hydrocephalus

Colloid cysts characteristically arise from the roof of the third ventricle near the foramen of Monro, causing symptoms from obstructive hydrocephalus. However, atypical locations have been reported with various clinical presentations, growth patterns, and displacement of surrounding anatomic structures.

Here, we describe the interesting case of a patient with a large hemorrhagic cavum vergae colloid cyst presenting with anterograde amnesia soon after starting antiplatelet therapy. The patient did not have hydrocephalus on presentation and his amnesia persisted after complete removal of the hemorrhagic mass through transcallosal interforniceal approach.

To the best of our knowledge, this is the only reported instance of a colloid cyst presenting with amnesia in the absence of hydrocephalus. Pathophysiology as well as diagnostic and management strategies of hemorrhagic colloid cysts are discussed.