ABSTRACT
Intracranial aneurysms in neonatal period and early infancy may be resorbed spontaneously or due to removal of predisposing factors. Herein, we presented a rare case of vanishing of a large thrombosed intracranial aneurysm in a 25-day-old girl presented with head enlargement and vomiting. Magnetic resonance imaging [MRI] revealed a severe hydrocephalus accompanied by a 1.5-cm aneurysm at the bifurcation of the right middle cerebral artery [MCA]. Doppler ultrasonography confirmed a flow with a magnitude almost similar to that of the right MCA flow, inside the mass located adjacent to it. The hydrocephalus was managed by ventriculo-peritoneal [VP] shunt. The patient underwent a conservative observation for several months. Subsequently, the aneurysm was vanished in control images