High-flow priapism: a novel way of lateralizing the lesion in radiologically inapparent cases.

High-flow priapism is a rare entity, which is typically diagnosed with the help of either color flow Doppler ultrasound or arteriogram. In the case presented, both of these diagnostic modalities were unsuccessful in uncovering a vascular lesion. The patient underwent an empiric selective embolization of the left pudendal artery followed by a repeat angiogram of the right because of persistent tumescence. This procedure uncovered a previously unseen arteriolacunar fistula, which was treated successfully with a second selective embolization.