High-Flow Priapism Embolization

Background and indications

High-flow (arterial, non-ischemic) priapism is a prolonged erection caused by an arteriocavernosal fistula, most commonly post-traumatic (perineal trauma, straddle injury). Unlike venous (ischemic) priapism (urological emergency), arterial priapism is painless and does not cause cavernosal necrosis. Internal pudendal artery (cavernosal branch) embolization is the reference treatment.

Pre-procedure assessment

Assessment includes penile Doppler ultrasound (high-flow confirmation, arteriocavernosal fistula visualization), cavernosal blood gas analysis (arterial red blood — high PO2, unlike ischemic priapism), and pelvic CT angiography if needed.

Procedure

Under local anesthesia and sedation, a catheter is introduced through the femoral artery. Selective pelvic arteriography identifies the arteriocavernosal fistula (contrast extravasation into the corpus cavernosum). The internal pudendal artery is super-selectively catheterized and the fistula embolized with resorbable materials (gelatin — erectile function preservation) or microcoils. Resorbable materials are preferred to maximize erectile function preservation. The procedure takes 1 to 2 hours.

Results and scientific evidence

Embolization offers 75-90% success rate for priapism resolution. Erectile function is preserved in 80-90% of cases. Recurrence rate is 10-30%, treatable by second embolization. Embolization is recommended as first-line treatment by EAU and AUA guidelines for arterial priapism (Salonia et al., European Urology, 2014; DOI: 10.1016/j.eururo.2013.11.008).

Risks and complications

Erectile dysfunction (10-20%, often transient), non-target embolization (< 2%), access site hematoma (3-5%), recurrence (10-30%). Resorbable materials reduce permanent dysfunction risk.

Recovery

1-2 night hospitalization. Progressive detumescence in 24-48h. Control Doppler ultrasound at 1-2 weeks.

Practical information

The procedure is performed as an inpatient. It is performed by an interventional radiologist, in coordination with the urologist.