Arterial Revascularization
Although, vascular blocks are fairly common in a person with diabetes, blocks to the arteries supplying the penis are rarely the cause of the erectile dysfunction.

It is only appropriate in young patients with proven arteriogenic impotence due to congenital vascular anomalies or traumatic injuries to the pudendal or penile arteries

In fact, even if one considers the full spectrum of erectile dysfunction, irrespective of the somatic cause, only 2% to 3% of all patients meet these criteria for penile arterial bypass.

Most centers have rigid inclusion criteria before undertaking such procedures. Although, these may differ from place to place, the general consensus seems to be that Penile arterial revascularization is indicated for only highly selected patients, young men (less than 45 years old) who have penile, perineal, or pelvic trauma and are either not at risk for atherosclerosis or have modifiable risk factors.

Contraindications are:

• Presence of significant corporal veno-occlusive dysfunction (particularly early drainage into the glans penis or corpus spongiosum, which reflects corporal smooth muscle myopathy and/or collagen deposition)
• Age over 45 to 50 years
• Generalized atherosclerosis
• High serum lipids
• Lack of specific focal lesions affecting internal pudendal arteries or internal branches
• Insulin-dependent diabetes mellitus
• Inability to stop using tobacco in any form.

Selective arteriography is recommended only for men who are candidates for arterial revasculization. These are usually young, healthy men who have suffered trauma to the penis or to the area under the scrotum known as the perineum. Prior to proceeding with an arteriogram, which is a very invasive procedure, a Duplex Doppler examination showing the presence of poor blood flow and indicating a probable arterial lesion should be performed. If an obstruction is visualized, it is important to document whether there is flow back through the blockage to the point of obstruction so that the patient will be sure to benefit from the procedure.

The objective of the surgery is to increase the blood flow to the corporal body and therefore improve the erections. The best candidates for surgery are men who have poor erections with spontaneous erections absent and in whom all studies indicate a pure arterial component. Patients with other diseases such as diabetes or heavy smokers are poor candidates for this type of operation.

Ideally, arterial surgery should be the way to treat erectile dysfunction since it seems logical that a damaged or blocked artery could easily be bypassed to provide the necessary blood needed to maintain an erection. Unfortunately, this is not the case because the patients who have this distinct arterial lesion are very limited. Patients who undergo arteriography should be highly motivated and have a complete workup to rule out all other causes of erectile dysfunction, including hormonal problems or venous leaks. Patients should not proceed with arteriography unless they are good candidates for revascularization.

Candidates should have a percentage of smooth muscle tissue of at least 29%. In studies of selected patients there was improvement in erectile dysfunction in 50% to 75% of men after five years.

In the ideal procedure, if the common penile artery bifurcation exists, the inferior epigastric artery is connected end-to-end or end-to-side and retrograde flow is achieved into the dorsal artery, If, as in 20% of patients, the sole source of arterial flow to the lacunar spaces is a significant penetrating artery from the dorsal to the cavernosal artery, the procedure is done end-to-side.

At many centers, the procedure is effected by taking an artery from a leg and then surgically connecting it to the arteries at the back of the penis, bypassing the blockages and restoring blood flow. In some patients, the only viable recourse for corporal revascularization is arterialization of an isolated segment of the deep dorsal vein.

Arterial Revascularization. In arterial revascularization of the penis, (top) the inferior epigastric artery may be connected end-to-side to the dorsal artery or (bottom) an isolated segment of deep dorsal vein may be arterialized.

The prognosis for the success of reconstructive arterial surgery in reversing ED is 50% to 70%, including conversion to successful injection therapy. Although few patients who undergo revascularization have complications, side effects include:

Penile Venous Surgery
In the era of highly effective oral and injectable drug therapy, penile venous surgery must be considered historical. With very few exceptions (cases of ectopic veins in young men), there is no justification for pursuing this kind of treatment in ED patients, especially because most of these procedures end in failure.

A large number of men suffer from erectile dysfunction as a result of venous leak - a condition that prevents the storage of blood in the penis. Without the storage of blood, an erection cannot be maintained. In men with venous leak, blood flows out of the penis as quickly as it flows in. The penis does not become fully erect or loses its erection quickly.

The trapping of blood within the corpora cavernosa by decreasing venous return is a necessary step toward achieving and maintaining erection. Veno-occlusive incompetence or dysfunction is defined as the inability to trap blood within the corpora cavernosa to achieve and maintain erection.

The current study of choice for diagnosing veno-occlusive dysfunction is cavernosography and pharmacologic cavernosometry. These procedures are usually carried out at highly specialized centers where the surgeosn have a special interest in researching venous leaks as the cause of erectile dysfunction.

For most practical purposes, venous dysfunction can be inferred from the finding of a normal arterial response to intracavernosal injection in the presence of a poor erectile response.

Venous leakage is a relatively common cause of erectile dysfunction. An inability to achieve and maintain the full erection occurs because blood leaks out in the presence of an adequate arterial inflow due to a damaged veno-corporo-occlusive mechanism. There are five theorized types of venogenic impotence.

Type 1 is due to the presence of an excessively large number of veins exiting the corporal body. This is probably congenital and is seen in young men with primary erectile dysfunction.

Type 2 is the weakening of the tough outer membrane of the corporal membrane of the corporal body known as the tunica albuginea, resulting in poor compression of the veins, such as in elderly men. I consider this a wear-and-tear phenomenon.

Type 3 is the loss of compliance of the cavernosal smooth muscle because of Peyronie's disease or scarring degeneration in patients with severe hardening of the arteries.

Type 4 is poor relaxation of the cavernous smooth muscle due to inadequate release of the hormones it takes to create an erection. This is typically common in heavy smokers.

Type 5 results from abnormal communications between the corpora cavernosa and the spongiosum due to trauma or a prior procedure to treat priapism.

Patients with pure erectile dysfunction on the basis of a venous leak are rare, but many men have venous leakage as a component of their erectile dysfunction

The first choice for patients who have venous leakage is a vacuum erection device or treatment with intercavernosal injections. The only patients who are candidates for a venous leakage operation are patients who have failed simple, noninvasive treatments.

When it has been determined that the patient is a good candidate for repair, the idea of treatment is to find the vein that is the source of the leakage and then tie it off. If the leaking vessel is near the base of the body, then an incision is made over that area. We feel that good candidates for venous surgery are those who have identified a localized leak and who have had a complete workup to rule out all the obvious causes for erectile dysfunction, including the Duplex Doppler examination. Surgical candidates should be nonsmokers, young, and have no other medical problems. A preoperative X-ray examination called the cavernosogram should identify the site of the leaking vessel.

The complications with this type of operation are numerous, as with all operations. They include numbness of the penis, scarring, a shortening or twisting of the penis, and painful erections.

Venous ligation is performed when the penis is unable to store a sufficient amount of blood to maintain an erection. This operation ties off or removes veins that are causing an excessive amount of blood to drain from the erection chambers. Success rate is estimated at between 40% and 50% initially, but drops to 15% over the long term. It is, of course, important to find a surgeon experienced in this surgery.

Venous Ligation Surgery
Deep penile vein dissection is indicated in an even more select group of men. Veno-occlusion dysfunction most commonly results from smooth muscle disease. Thus the rare patient is a young man with focal corporal veno-occlusive dysfunction caused by trauma who has normal arterial outflow or who wants a better response to intracavernosal pharmacotherapy. The patient should understand that improvement may be temporary. In the past, venous ligation has also been performed as an adjunct procedure to revascularization.

Vein Dissection and Ligation. In preparation for vein dissection, the penile shaft is inverted into a standard anterior scrotal incision. (Top left) As the penile skin is stripped away from the shaft, a junction between the deep and superficial penile veins may be identified and ligated. (Top right) A 19-gauge needle is placed into one corpora, and a pharmacologic agent followed by indigo carmine is injected to visualize effluxing veins. The infrapubic suspensory ligament is dissected (the ligament is approximated with silk ligature at the end of the procedure). A large silk suture is placed around the deep dorsal vein in the infrapubic region. (Bottom) In this illustration, Buck's fascia has been removed to show the orientation of the deep dorsal vein with the artery to the left. The vein is dissected along the penile shaft to the region of the glans, where several trunks coalesce to form it. Circumflex and direct emissary veins that drain into the deep dorsal vein are identified and divided between clamps or ligatures during the dissection to approximately 1 to 2 cm from the glans edge. Controlled cavernosography is performed after surgery to compare with preoperative data.