Priapism

Priapism is classified into three groups: ischemic (low-flow), nonischemic (high-flow), and recurrent ischemic. In women Priapism in women (continued, painful erection of the clitoris) is significantly rarer than priapism in men and is known as clitoral priapism or clitorism. Only a few case reports of women experiencing clitoral priapism exist. ==Signs and symptoms==

Complications Because ischemic priapism causes the blood to remain in the penis for unusually long periods of time, the blood becomes deprived of oxygen, which can cause damage to the penile tissue. Such damage can result in erectile dysfunction or disfigurement of the penis. In extreme cases, if the penis develops severe vascular disease, the priapism can result in penile gangrene. Low-flow priapism Causes of low-flow priapism include sickle cell anemia (most common in children), leukemia, and other blood dyscrasias such as thalassemia and multiple myeloma, and the use of various drugs, as well as cancers. Other conditions that can cause priapism include Fabry's disease, as well as neurologic disorders such as spinal cord lesions and spinal cord trauma (priapism has been reported in people who have been hanged; see death erection). Priapism can also be caused by reactions to medications. The most common medications that cause priapism are intra-cavernous injections for the treatment of erectile dysfunction (papaverine, alprostadil). Other medication groups reported are antihypertensives (e.g. Doxazosin), antipsychotics (e.g., chlorpromazine, clozapine), antidepressants (most notably trazodone), anti-convulsant and mood stabilizer drugs such as sodium valproate. Anticoagulants, cantharides (Spanish Fly) and recreational drugs (alcohol, heroin and cocaine) have been associated. Priapism is also known to occur from bites of the Brazilian wandering spider. High-flow priapism Causes of high-flow priapism include: • blunt trauma to the perineum or penis, with laceration of the cavernous artery, which can generate an arterial-lacunar fistula. • Anticoagulants (heparin and warfarin). • Antihypertensives (i.e., hydralazine, guanethidine and propranolol). • Hormones (i.e., gonadotropin releasing hormone and testosterone). ==Diagnosis==

The diagnosis is often based on the history of the condition as well as a physical exam. In low-flow (ischemic) priapism the flow in the cavernous arteries is reduced or absent. As the condition progresses, there is an increase in echogenicity of the corpora cavernosa, attributed to tissue edema. Eventually, changes in the echotexture of the corpora cavernosa can be observed due to the fibrotic transformation generated by tissue anoxia. In high-flow priapism normal or increased, turbulent blood flow in the cavernous arteries is seen. The area surrounding the fistula presents a hypoechoic, irregular lesion in the cavernous tissue. ==Treatment==

Medical evaluation is recommended for erections that last for longer than four hours. Pain can often be reduced with a dorsal penile nerve block or penile ring block. Erection is largely a parasympathetic response, so the sympathetic action of pseudoephedrine may serve to relieve this condition. Pseudoephedrine is an alpha-agonist agent that exerts a constriction effect on smooth muscle of corpora cavernosum, which in turn facilitates venous outflow. Pseudoephedrine is no longer available in some countries. Aspiration For those with ischemic priapism, the initial treatment is typically aspiration of blood from the corpus cavernosum. Proximal shunts, such as the Quackel's, are more involved and entail operative dissection in the perineum where the corpora meet the spongiosum while making an incision in both and suturing both openings together. Shunts created between the corpora cavernosa and great saphenous vein called a Grayhack shunt can be done though this technique is rarely used. As the complication rates with prolonged priapism are high, early penile prosthesis implantation may be considered. ==History==

Persistent semi-erections and intermittent states of prolonged erections have historically been sometimes called semi-priapism. Terminology The name comes from the Greek god Priapus (), a fertility god, often represented with a disproportionately large phallus. ==See also==