RUPTURED DISTAL ANTERIOR CHOROIDAL ARTERY ANEURYSM PRESENTING WITH CASTING INTRAVENTRICULAR HEMORRHAGE

This report describes a rare case of a distal anterior choroidal arter y aneurysm which developed intraventricular haemorrhage without subara chnoid haemorrhage as shown on computerized tomographic (CT) scan. A 6 9-year-old hypertensive man suddenly became unconscious. An emergency CT scan showed a severe intraventricular haemorrhage and a small round low-dense lesion within the haematoma at the right trigone. The haema toma with obstructive hydrocephalus made the lateral ventricles larger on the right than on the left. CT scan could not detect any subarachn oid haemorrhage. Right interal carotid angiography revealed a saccular aneurysm at the plexal point of the right anterior choroidal artery. We approached the aneurysm and the small round lesion through the trig one via a right temporo-occipital corticotomy. We could clip the aneur ysmal neck and remove the intraventricular haematoma and the papillary cystic mass (corresponding to the small round lesion on CT scan) tota lly in one sitting. Histological examination revealed the aneurysm to be a true one and the papillary cystic mass to be a choroid plexus cys t.