Almost 3.000 years ago, the Chinese already used ivory sticks to complete and assist penile erection. The world effective experience dates back to 30 years, with the advent of the first synthetic-material prosthesis, the acrylic resin, placed between the tunica albuginea and Buck's fascia. Later, penile prostheses as they are known today turned up, placed inside the corpora cavernosa.

Since the development of other options, prostheses have assumed a much smaller role in the treatment of erectile dysfunction. However, various types of prostheses are still in routine use are:

a) Semirigid, malleable rods can also be inserted into the penis to provide penile erection.

b) Two piece inflatable prosthesis, the pump and reservoir are in the scrotum and are used to inflate the cylinders into the erect position. The cylinders are then deflated by pressing a valve at the base of the pump to return the fluid to the reservoir

c) In a three piece inflatable prosthesis, the pump is in the scrotum and the reservoir is in the abdomen.

Which Implant?
Each type has advantages and disadvantages, which should be matched to the patient's individual preferences.

Semirigid, Malleable Rods
These devices are the same shape and size at all times, but may be straightened or flexed for concealment. They have less tendency than the inflatable devices for mechanical wear and are surgically easier to place. However, penile flaccidity, concealment, and girth are not optimal. The rods are usually placed through circumcision-like or penile-scrotal incisions.

The malleable prosthesis does not change the length and girth of the penis during "tumescence" and "detumescence." Malleable implants usually consist of paired rods, which are inserted surgically into the corpora cavernosa, the twin chambers running the length of the penis. The user manually adjusts the position of the penis and, therefore, the rods. Adjustment does not affect the width or length of the penis.

The semirigid device consists of two rods that are easier and less expensive to implant than the inflatable cylinders. Once implanted, the semirigid device needs no follow-up adjustments, however it produces a penis which constantly remains semi-erect

The malleable prosthesis is preferable for patients with poor manual dexterity or those with spinal cord injuries who need a prosthesis to facilitate application of a condom catheter.

The malleable (shown at the right) are rods that can be bent so the penis can folded down or up to be erect. Two rods are inserted.

Implantation of the multicomponent inflatable prosthesis requires placement of inflatable cylinders into each corpus, the reservoir into the perivesical or preperitoneal space, and the pump into the scrotum (on the right side for right-handed patients, on the left for the left-handed). This device connects through a tube to a flexible fluid reservoir and a pump. The pump is shaped like a testicle and inserted in the scrotum. When the pump is squeezed, the fluid is forced into the inflatable cylinders implanted inside the penis, producing an erection.

Both types increase in girth, and the three-piece devices also increase in length.

The inflatable cylinders produce a more natural effect. The patient is able to simulate an erection by using a pump located in the scrotum.

Two-piece systems are particularly useful for patients in whom placement of an abdominal reservoir would be difficult or impossible. They are also somewhat easier to place surgically, but produce approximately 80% to 85% of the girth change and rigidity of the three-piece unit and less flaccidity when deflated.

Two-piece system
The three-piece devices offer the best flaccidity, rigidity, and girth, particularly suitable for patients who have a significant curvature of the penis due to Peyronie's disease.

Three-piece device
Three piece penile prosthesis in which the pump alone sits in the scrotum and the reservoir lies in the lower abdominal wall