Ischemic priapism

In organ-bath preparations using isolated rabbit corpus cavernosum, Broderick et al. (1994) suggest that corporeal smooth muscle tone, spontaneous contractile activity and the response to a-agonists depends on the state of corporal oxygenation. These observations might be an explanation for the failure of locally administered a-antagonists to relieve ischemic priapism because of smooth muscle paralysis. 

The onset of a post-traumatic, high-flow priapism may occur up to 72 h after the injury. Pain is never as severe as in an ischemic priapism the penis is often not maximally rigid and pulsation may be recognized. 

A thorough history and physical examination are prerequisites to diagnostic accuracy. The fundamental aim of the initial phase of assessment is to distinguish arterial from ischemic priapism. The sexual and medical history should especially focus on medications, trauma and predisposing comorbidities. Presence or absence of pain is a fairly reliable predictor oflow-flow versus high-flow priapism, respectively. Absence of pain in arterial priapism frequently results in less patient anxiety and discomfort as compared with veno-occlusive priapism. Consequently, patients with arterial priapism may present days or even weeks after the original injury (Ricciardi et al. 1993). 

Berger R, Billups K, Brock G et al (2001) Report of the American Foundation for Urologic Disease (AFUD) Thought Leader Panel for evaluation and treatment of priapism. Int J Impot Res 13 [Suppl 5] S39-43 Bertholon F, Krajewski Y, el Allali A (1996) [Adverse effects priapism caused by paroxetine]. Ann Med Psychol (Paris) 154 145-146 discussion 146-147 Broderick GA, Gordon D, Hypolite J, Levin RM (1994) Anoxia and corporal smooth muscle dysfunction a model for ischemic priapism. J Urol 151 259-262 Broderick GA, Harkaway R (1994) Pharmacologic erection time-dependent changes in the corporal environment. Int J Impot Res 6 9-16... 

As described in Chapter 9, priapism is an uncommon medical condition defined as persistent tumescence or erection not associated with sexual desire or stimulation (Pautler and Brock 2001). Different pathophysiologies have been described. Low-flow or ischemic priapism is characterized by complete painful erection secondary to inadequate venous outflow leading to hypoxia, acidosis and pain (Lue et al. 1986 Pautler and Brock 2001). High-flow priapism is usually associated with penile or perineal blunt trauma and cavernosal artery tear (Pautler and Brock 2001). Patients... 

Although diagnosis of priapism and differentiations between the non-ischemic and the ischemic sub-... 

Imaging is usually not required before the operation in patients with ischemic priapism, because this condition is considered a urological emergency, and history and examination are often sufficient to make the diagnosis. It is commonly accepted that prompt treatment is mandatory in all patients with low-flow priapism because recovery of function becomes increasingly unlikely over time (Winter and McDowell 1988). 

Dynamic infusion cavernosometry and caver-nosography have been used to document the absence of cavernosal venous outflow in patients with ischemic low-flow priapism (Goto et al. 1999) and to identify postischemic fibrotic cavernosal tissue changes (Velcek and Evans 1982 Van der Horst et al. 2003). Clinical evaluation and ultrasound, however, provide enough useful information to manage the patients. 

During the follow-up of ischemic priapism this examination allows evaluation of circumscribed (Park et al. 2001) or diffuse fibrous changes of the cavernous tissue as heterogeneous areas oflowsignal intensity on both Tl- and T2 weighted sequences. 

Vascular Surgery for Impotence 137 Circumcision 139 Penile Augmentation Procedures 140 Shunt Surgery for Ischemic Priapism 140 Sex Reassignment Surgery 141 Urethral Surgery 141... 

Low-flow, ischemic priapism must be treated as soon as possible because prolonged cavernosal ischemia leads to corporeal fibrosis and permanent erectile dysfunction. If medical management is unsuccessful, surgical management must be considered. 

As described in Chapter 15, the principle of surgical correction of ischemic priapism is connecting the engorged corpora cavernosa with the glans, the corpus spongiosum or veins. Glans-cavernosum anas-... 

Fig. 16.10. Glans-corpus cavernosum shunt in patients with ischemic priapism. Al-Ghorab technique. The shunt (open arrows) appears as an interruption of the tunica albuginea (arrowheads) connecting the corpus cavernosum with the glans...

Fig. 18.7. Diffuse penile fibrosis following prolonged ischemic priapism. Color Doppler axial image obtained after prostaglandin injection shows small peripheral vessels feeding the outer portion of the corpora cavernosa. Cavernosal arteries are obliterated...

Different examination techniques should be used to image penile vasculature with microbubble contrast agents. While patients with penile malformations, primary penile tumors, and Peyronie s disease are evaluated after cavernosal injection of vasoactive drugs to obtain erection, patients with trauma, ischemic priapism, and penile metastases are examined in hasal condition. 

No enhancement of the cavernosal arteries or filling of the central portion of the corpora cavernosa is detected in patients with ischemic priapism. Occasionally, the outer portion of the corpora cavernosa may enhance via collateral pathways. Conversely, enhancement of the glans, of the cor-... 

Fig. 21.10a,b. Cavernosal tissue scar andfibrosis. Axial scans obtained after intravenous microbubble injection, a Cavernosal tissue scar within the left corpus cavernosum presenting as a circumscribed area ( ) in which contrast enhancement is lacking, b Diffuse penile fibrosis following ischemic priapism. Peripheral enhancement ofthe corpora cavernosa is appreciable, while the central portion does not enhance... 

Denton K, KoUi V, Sharma A. Ziprasidone-induced ischemic priapism requiring surgical intervention a case report. Prim Care Companion CNS Disord 2013 15(1). 

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