Arterial embolization in the treatment of post-traumatic priapism

Priapism is a prolonged penile erection not associated with sexual arousal. Two types of priapism have been described: the more common one is the "veno-occlusive" priapism and can be frequently observed as the consequence of an intracavernosal injection of vaso-active drugs for the treatment of erectile dysfunction. The less common type of priapism is known as "high flow" priapism and usually follows perineal or direct penile trauma. The clinical presentation in case of high flow priapism is quite typical: hystory of recent penile or perineal trauma followed, by the onset of a painless, incomplete and constant erection of the penis. A color-flow Doppler sonogram should be performed as first diagnostic step: this examination allows to identify the presence of patent cavernous arteries and prominent venous drainage with focal area of high flow turbulence along the pathway of one or both the cavernous arteries. An arterial blood sample taken from the corpora will confirm the diagnosis. At first, conservative therapeutical attempts can be suggested, with mechanical external compression of the perineum, the use of ice packs, corporeal aspiration and irrigation with saline. Besides, intracorporeal administration of alpha-agonists and methylene blue should be performed. Unfortunately, these conservative measures often result unsuccessful, and more invasive approaches must be considered. The radiological superselective transcatheter embolization of the proximal artery supplying arterial-lacunar fistula should be the present treatment of choice in these cases of high-flow priapism refractory to conservative and medical treatments. The first successful management of high flow priapism by selective arterial embolization was reported by Wear and coworkers in 1977. Autologous clots and gelatine sponge have been extensively used and become very popular as the embolic agent. More recently, platinum microcoils have been proposed with the aim to achieve more precise and selective embolization. In our single-case-experience on the treatment of high flow priapism by arterial embolization, we used the recently introduced tungsten microcoils. At the time of the follow-up, 2 months later, patient reported satisfactory intercourse with an approximately 75% of penile rigidity. By comparison with microsurgical ligature of the damaged vessel, selective embolization is, at least theoretically, a less invasive procedure, particularly with reference to the trauma caused to the erectile tissue. High-flow priapism is a fairly rare urological pathology which does not require immediate and emergency treatment (as is the case, instead, with venous-occlusive priapism), since the risk of post-ischaemic fibrosis is excluded thanks to the fact that oxygen is supplied to the cavernous tissue. Once the diagnosis has been established with certainty, therefore, the specialist has the necessary time at disposal to arrange for the most appropriate therapeutic steps. When, as is frequently the case, conservative measures prove ineffective, the current treatment of choice for cases of fistula of the cavernous artery would appear to be superselective embolization of the artery, provided same can be performed at specialized centres and by experienced personnel.