Ruptured aneurysm of the medial posterior choroidal artery in the pineal region: A rare location easily missed.

Aneurysms of the pineal region are rare and theoretically could arise from the medial posterior choroidal artery (MPChoA) or lateral posterior choroidal arteries (LPChoA). A 64-year-old lady with subarachnoid haemorrhage (SAH) and intraventricular haemorrhage (IVH) due to a ruptured MPChoA aneurysm was treated with microsurgical aneurysm excision via an occipital interhemispheric approach. This case demonstrates the importance of being mindful of rare aneurysm locations when initial vascular imaging in SAH appears normal.