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Implantation of a penile prosthesis is one of several options available for the treatment of impotence. The penis consists of three hollow tubes running along the length of the shaft. One of these, the urethra, runs along the bottom of the penis and brings urine from the bladder out through the end of the penis. The other two matched tubes running side-by-side on the top of the penis are constructed much like an automobile tire with an outer tube and an inner tube. The erection is created by the two inner tubes filling and pushing against the outer tubes, much like a tire that is inflated with air.

One of the treatment options for erectile dysfunction is the placement of prosthetic inner tubes within the penis to mimic the inflation process and create an erection. Penile implants were first used in the 1950s, and since then further advances have occurred. Different types of prostheses have been developed, and hundreds of thousands of men throughout the world have been successfully treated with penile implants.

Today there are three types of penile prostheses: the semi-rigid implant, the inflatable implant and a self-contained inflatable implant. 

Semi-rigid implants are paired, silicone-covered, malleable (bendable) metal rods. The semi-rigid prosthesis allows the penis to be rigid enough for penetration, but the malleable rods allow it to be flexible enough to allow concealment in a curved position. It is the simplest of all prostheses and has the least chance of mechanical failure. It is also the simplest to place. 

One major limitation is that the penis is always semi-erect. Even thought it can bend, concealment is a potential problem when wearing some types of clothing. Another disadvantage is that the prosthesis does not inflate, so the erection achieved is only from the size and rigidity of the prosthesis.

Inflatable prostheses are the most natural of the implants. These are soft, paired inner tubes made of silicone or bioflex, which are inert plastics. The inner tubes are filled with a solution that comes from a small reservoir placed under the muscles of the abdomen. A pump is used to transfer the fluid from the reservoir to the penile cylinders (inner tubes). The more fluid that is pumped into the inner tubes, the firmer and larger the erection. When the erection is no longer desired, the fluid returns to the reservoir, leaving the penis soft and pliable. 

A major advantage of an inflatable penile implant is a more natural erection with total patient control, both in the amount of fluid that is put into the penis and the time the erection is desired. The erection will last indefinitely until the patient transfers the fluid back into the reservoir. One major disadvantage is that the surgical implantation is a little more complicated than a simple semi-rigid implant. Also, with the multiple parts there is a higher chance of mechanical failure which might require revision or repair. Many of the companies do have insurance policies to cover part or all of the costs of the prosthesis replacement but not the surgical or hospital fees. 

Self-contained inflatable implants are paired silicone cylinders which have a pump at the very tip of the prosthesis, along with a reservoir within the shaft that transfers fluid in such a way that the cylinder becomes firm. 

The advantage of this type of prosthesis is that the surgery is somewhat simpler than the multicomponent prosthesis.

Implants are effective in treating almost every cause of impotence. There is over a 90 percent success rate when both partners are informed of the nature and limitations of the prosthesis. Prostheses require no further treatment after implantation, and there is no external equipment which might have negative connotations to the partner. No medicines or injections are needed, and once the prosthesis is placed and functioning there are no further costs. The newer prostheses are very reliable and the chance of mechanical failure is very low, in the range of 2 to 4 percent per year.

Some insurance policies will cover the cost of prostheses; this can be established through our business office. Patients who are considering a prosthesis should be aware that other types of therapy might be available, including vacuum devices and self-injection therapy.