Aberrant inferior petrosal sinus: unusual transvenous approach to the cavernous sinus.

Two patients with vascular lesions of the cavernous sinus (CS) undergoing endovascular management are reported. During transvenous embolization an unusually low termination of the inferior petrosal sinus (IPS) was observed. In both patients, we were able to catheterize the CS using this aberrant venous route. Knowledge of this variant can be crucial for a successful transvenous approach and treatment of vascular lesions involving the cavernous sinus.