Penile Prosthesis Surgery

While many men rely on medical treatment in order to develop an erection, penile prosthesis surgery is an option that has been found to be a very satisfying treatment for both men and their partners. In fact, prior to the development of the phosphodiesterase inhibitors (PDE-5 inhibitors), studies confirmed that penile prosthesis surgery was much more effective and satisfying than vacuum devices, intracavernous injection therapy, and transurethral therapy. Having a penile prosthesis placed is a very personal decision. Before choosing to have a penile prosthesis implanted, you should speak with your doctor about whether this is right for you.

The Device:
The two basic categories of penile prostheses available are semirigid penile prostheses and inflatable penile prostheses. The semirigid prosthesis is a device that essentially stays firm all the time. It is malleable, and when someone has one of these devices placed, he simply bends it upward in order to allow for penetration, or downward when it is not in use. The advantage of the semirigid penile prosthesis is that it is a very simple device to implant, and the time needed to recover from this surgery is short. It is an easy prosthesis to use and is particularly ideal for those men who have poor manual dexterity. The major disadvantage of the semirigid prosthesis is that it is somewhat difficult to conceal. This is particularly true for men that enjoy wearing tight clothing and certain bathing suits. Potential risks associated with implantation of one of these devices are similar to those risks associated with the placement of an inflatable device (see below). Because these devices are a made with a single component, fewer mechanical problems can occur over time. Sometimes, with wear and tear, the device does lose its rigidity and needs to be exchanged, usually after a period of many years.

Inflatable penile prostheses are multicomponent devices that allow for the transfer of fluid within the components of the device in order to create a rigid erection or a very soft penis when in the flaccid state. The three components in these prostheses include 1) the two corporeal cylinders, 2) the pump, and 3) the reservoir.
This illustration demonstrates the basic anatomy of a penile prosthesis. The corporeal cylinders are the two components that are placed in the actual penis itself. They are responsible for getting hard when the device is in use, or soft when it is not. The pump is the portion of the device that sits in the scrotum, and is manually controlled. By squeezing a portion of the pump, the device inflates (gets hard) or deflates (gets soft). The third component of these devices is the reservoir, which is implanted in the lower pelvis. This is usually done without having to make a second incision. The reservoir is responsible for holding the fluid in the device when the penis is soft, or sending the fluid to the cylinders when the penis is hard.

Two corporations, the Mentor Corporation and American Medical Systems produce the three inflatable prosthesis models that are most widely used today. While the basic concept of a hydraulic system that allows for transfer of fluid in order to allow for device deployment is similar between the two brands, there are a number of differences in the materials that are used in manufacturing these devices, as well as various aspects of the design of the products. Both of these corporations have their own websites which can be accessed by the consumer to learn about the details of production and design that may differ.

Implantation of a Penile Prosthesis
The implantation of a penile prosthesis usually requires regional (spinal or epidural) anesthesia or general anesthesia. A small incision is made in the scrotum or in the area just above the penis (the infrapubic region). The choice of where the incision is made is based upon the preference of the surgeon, and there is no difference in the complication rate of either of these incisions when performed by surgeons who have a lot of experience in prosthesis surgery. A foley catheter is a drainage tube that is placed into the bladder through the male urethra. This is the tube at the center of the penis that men urinate through. This catheter is usually placed at the beginning of surgery in order to help the surgeon identify the urethra, and allows for a way to monitor the patient’s urine output during and after surgery. The corpora cavernosa are the two areas in the penis that become engorged during an erection. It is within these two corpora cavernosa that the cylinders of the penile prosthesis are implanted. In order to implant the cylinders, the surgeon must provide a tunnel through the tissue of these chambers so that a device can be implanted. By initially passing an instrument through the center of the corpora cavernosum and then dilating this tunnel with a variety of instruments that have been designed for this purpose, a space is created within both of the corpora cavernosa, which can accommodate the penile prosthesis cylinders. The cylinders are placed in the corpora cavernosa with the use of an instrument which pushes the cylinders distally within the shaft of the penis to the glans. At the very end of the cylinders, there is a suture which is pulled through the tip of the penis with a small needle. By pulling up on the suture, the device is able to be pulled up into the penis so that it does not kink or fold within the chambers of the penis.

I am often asked the question: “Doctor, can you give me a larger sized implant so that my penis will be longer after surgery?” Unfortunately, the answer is ‘no’. The corporeal cylinders are measured to fit into the penis in order to approximate the exact size of the corpora cavernosa. This measurement is made in the operating room during surgery, and is not a measurement of the size of the shaft of the penis itself. It accounts for the measurement of the entire penis- the part that you can see (the shaft), and the part that you cannot see (the crura). By putting in a device that is larger than the measured size of the penis, the penis will not get bigger. In fact, the device will fold upon itself within the penis. This may cause bending of the device inside of the penis during erection, penile curvature, and penile pain. In addition it may increase both the risk of erosion through the corpora cavernosum and device malfunction.

After the cylinders are routed into the corporal chambers, the scrotal pump is placed. This should be placed in a very low position within the scrotum and a small pouch is made, which holds it in place here. Following surgery, patients are asked to pull the scrotal pump down in order that it does not retract upward as healing occurs.

The reservoir is the final component to be placed, usually through the same incision that the rest of the device is placed. Sometimes, in patients who have had previous surgery on their bladder or prostate, a second incision is made in order to place the reservoir safely in the pelvis. Once the reservoir is placed, the tubing from the pump and the reservoir is connected and the tissue overlying the device is closed. The skin is closed with an absorbable suture and the patient is then sent to the recovery room.

What to expect after undergoing penile prosthesis surgery.
The first 24 hours following penile implant surgery can be painful. Ice is applied locally to the penis and scrotum, and narcotics (morphine or meperidine) are given as much as is needed to keep you comfortable. The narcotic injections are gradually replaced by oral narcotics (percocet or vicodin) and acetaminophen (Tylenol). Intravenous antibiotics are administered before and directly after the surgery is performed, and later these are changed to oral antibiotics which are given for a certain amount of time following surgery, at the discretion of the surgeon. A clear liquid diet is advanced to a regular diet during the first 24 hours and there is a catheter in the penis which drains the bladder during this time. This is usually taken out on the first postoperative day after the patient is able to get up and go to the bathroom to urinate. Men undergoing penile prosthesis surgery are encouraged to not engage in any heavy lifting or strenuous physical activity for the first 4 to 6 weeks following surgery.

Showers are generally permitted after 24 hours, but we encourage our patients not to sit in a bath or go swimming for at least 4 to 6 weeks, to avoid soaking the wound, which is held together by dissolvable sutures.

After penile prosthesis surgery it is common to experience bruising of the scrotum, penis, or lower abdomen. Sometimes a drain is placed in the scrotum, which may prevent or improve the amount of postoperative bruising and swelling. This has recently been shown not to increase the risk of postoperative infections. The placement of a drain, which is generally removed after 24 hours is up to the discretion of the surgeon.

After the bladder catheter is removed on the morning after surgery, most patients may go home after voiding. It is important to rest following penile prosthesis surgery, however we also encourage our patients to walk as much as is possible in order to avoid prolonged periods of immobility. This can lead to a clot forming in the legs, called a deep vein thrombosis (DVT).

Usually we will want to see our penile prosthesis patients between one and two weeks following surgery to make sure that everything is healing well. Reasons to call your doctor after this surgery include, but are not limited to the following: 1) postoperative fevers greater than 100.5 degrees, 2) severe scrotal or penile swelling or if the penis and scrotum get more bruising than seen on the second or third postoperative day, 3) Nausea, vomiting or inability to move your bowels, 4) Inability to urinate. There is no substitute for good common sense, and if you believe that something is wrong or different than what you expected after surgery, do not hesitate to contact your doctor.

Complications of Penile Prostheses
While the majority of patients do very well with penile prosthesis surgery, some patients experience problems either at the time of the surgery, in the immediate postoperative period, or sometime several months or years following surgery. Complications that may occur in the operating room are rare in the patient who is undergoing a first time implant. Occasionally, the surgeon may inadvertently injure the urethra while dilating the corporal chambers. This usually occurs in the setting of severe scar tissue, which occurs in patients who have had a prior implant removed for infection or priapism. Usually when a urethral injury occurs the surgeon will need to abandon the procedure and leave the foley catheter in place for a longer period of time while the urethra heals. Placement of a penile prosthesis can then be once again tried several weeks later. Other intraoperative complications include bleeding, as well as perforation or crossover of the corporeal bodies during dilation. An experienced surgeon can usually correct these problems in the operating room.

The most devastating complication of penile prosthesis surgery is an infection of the device which usually requires complete removal of the device when it occurs. Fortunately, this occurs in less than 2-3% of first time implants. However, when a prosthesis becomes infected, it is very hard for the patient, who now needs to have the device removed. After removing the device from the penis, severe scarring of the penis usually occurs, which may cause the penis to become smaller and the scarring also makes it very difficult to put in a new penile prosthesis in the future. Unfortunately, the corporeal chambers of the penis are not very responsive to any medical therapy after a penile prosthesis is removed. As a result the patient is usually completely impotent until a new prosthesis is placed several weeks or months later. Occasionally, men will respond to vacuum devices or transurethral administration of alprostadil, however the overall rigidity and satisfaction experienced by the patient will be quite low.

Other complications of penile prosthesis surgery include: device malfunction, erosion or extrusion of the device outside of the corporeal chambers, and finally dissatisfaction with the particular device implanted. These complications are time dependent and the relative incidence of each is seen in the table below.

Satisfaction with Penile Prostheses:
A number of studies have confirmed that a penile prosthesis is associated with very high levels of sexual satisfaction for both the patient and his partner. Once someone has recovered from penile prosthesis surgery, the physician should spend some time working with you and teaching you how to inflate and deflate your penile prosthesis. Like riding a bicycle, it can be a little frustrating at first. However with practice and additional time spent working with your surgeon, almost everyone can learn to use these devices with great proficiency. You can expect to engage in sexual activity within 4-6 weeks after surgery. Recent studies have confirmed that during the first year there is a gradual improvement in overall proficiency and also the satisfaction that the patient and his partner achieve.

Revision Penile Prosthesis Surgery
Here at the Miller School of Medicine of the University of Miami, we have taken care of a very large number of patients who have had prior penile prosthesis surgery. Some of these men have had problems related to the function of the device, infections, or are not happy with the current device they have. We have one of the largest single center experiences with penile prosthesis revision surgery in the world and have presented our data at national meetings. What we have found is that patients undergoing a revision of their penile prosthesis can also experience the same level of satisfaction and device function as patients having their first implant.

Placement of a penile prosthesis is a very personal decision for men with erectile dysfunction. We encourage our patients to openly discuss their feelings with their partners. We also encourage partners to accompany a patient during the meetings with us. This not only provides a level of comfort for the patient, but it helps us to understand a little more about the relationship dynamics so that we can individualize the goals for the future of the sexual health of the couple.