(234) USING PERCUTANEOUS ULTRASOUND-GUIDED THROMBIN INJECTION AS A TREATMENT OF HIGH-FLOW PRIAPISM
Authors: Colquitt J , Warren C , Young S , Naidu S , Punjani N 
Published: December 2024

Abstract

Introduction
Nonischemic priapism typically occurs secondary to penile trauma, resulting in increased blood flow into the penis without decreased outflow resulting in a clinically non-painful, partially rigid erection. Per the American Urologic Association guidelines, surgical treatment is discouraged, and following conservative management, first line treatment is arteriography with selective arterial embolization. This procedure is generally highly successful but it does carry a risk of erectile dysfunction as well as priapism recurrence.

Objective
Herein we present the first known case of ultrasound guided thrombin injection in an adult for nonischemic priapism treatment after persistent priapism and arterial blush following arterial embolization.

Methods
A 44-year-old male presented with an eight-month history of partial tumescence and erectile dysfunction after an episode of unwitnessed loss of consciousness resulting in the subsequent development of gross hematuria and dysuria. Physical examination revealed a semi-firm penis with suspected high-flow priapism. He initially presented to the emergency department, whereby a cystogram and cross sectional abdominal imaging were unrevealing. Initial outpatient cystoscopy revealed a urethral polyp which resolved on subsequent repeat testing. Following this an outpatient penile duplex doppler ultrasound was performed demonstrating a right pseudoaneurysm at the penile base measuring 13 mm in diameter with an arteriovenous fistulous communication to the corpus cavernosum. MRI demonstrates fibrotic changes within the right corpus cavernosum and tunica albuginea indicating prior traumatic penile injury. At the time the patient had approximately 25% tumescence at rest and was only able to obtain a slightly firmer erection, but was still able to achieve orgasm. After extensive conversation and given a trial of conservative management, the patient elected to proceed with angioembolization. An angiogram was completed which demonstrated a blush of contrast in the area of the bulbourethral artery. Despite successful deployment and coil embolization of the pseudoaneurysm, there was noted continued filling of the patent pseudoaneurysm from small branched collateral vessels. The patient tolerated the procedure well, and had reduction of his baseline penile tumescence and some erectile function recovery, requiring oral phosphodiesterase-5 inhibitors. There was concern for complete occlusion of the dorsal penile artery with repeat embolization, which may ultimately worsen erectile dysfunction. He remained incompletely satisfied with response to oral therapy.

Results
It was ultimately decided to pursue an ultrasound guided thrombin injection, which has been reported in a handful of cases as a primary intervention for priapism. During the procedure, 200 units of thrombin was injected into the pseudoaneurysm under ultrasound guidance resulting in immediate cessation of arterial flow. Post-procedure angiography demonstrated effective resolution.

Conclusions
High-flow priapism is a relatively uncommon condition, managed generally with embolization as first line treatment, with success rates reported at 89 to 100% and recurrence only occurring in 30% of patients. Recurrence is generally treated with repeat embolization which has been reported to cause erectile dysfunction in 15 to 22% of cases. Percutaneous ultrasound-guided thrombin injection has the potential to be an excellent second-line treatment option for pseudoaneurysm closure in correcting nonischemic priapism, albeit with limited data, but suspected high efficacy and potentially diminished rates of erectile dysfunction.

Disclosure
No.