What are penile implants (prostheses)?
Penile prostheses, or penile implants, are an important treatment option for men with ED who have an established medical cause for ED, fail to respond to nonsurgical treatments (such as oral medications, vacuum devices, injection therapy, etc.) and who are motivated to have surgery to improve erectile function. Penile implant requires a permanent surgical procedure that cannot be reversed. It is important that men talk to their doctor about the advantages and possible drawbacks of having the procedure.
This procedure replaces the spongy tissue (corpora cavernosum) inside the penis with rigid, semi-rigid, or inflatable cylinders (depending on which type of penile implant is chosen). In all penile prostheses, the surgically inserted components are totally concealed within the body. After a penile implant, when a man desires an erection, he is able to produce a rigid erection on demand that enables him to have sexual relations. Penile implants do not typically lengthen the penis.
What types of implants are available?
There are diverse forms of penile implant options that can be categorized into two main types of implants, each of which come in a variety of diameters and lengths.
- Semi-rigid malleable (positionable) rods (also known as non-hydraulic)
- Inflatable (also referred to as hydraulic), which include two- and three-piece implants
Semi-rigid malleable (positionable) rods
Malleable models are not often used, nowadays only making up about 10% of devices implanted. Certain men should avoid this device (such as men with spinal cord injury, diabetics, and men who have had penile irradiation). The malleable penile implant requires surgical insertion of a pair of flexible rods within the erection chambers of the penis. The rods have an outer coating of silicone and inner stainless steel core or interlocking plastic joints. These joints enable the man to place the penis in either the erect or flaccid position. This type of implant produces a constant penile rigidity that merely needs to be lifted up, or bent, into the erect position to achieve an erection and sexual intimacy, or in the downward position for urination. As he does so, the rods inside his penis bend. Malleable penile implants can be bent in more than one place to create the desired erection. Three malleable devices exist at this time (AMS Malleable 650 and Dura-II devices, and the Mentor Acu-Form prosthesis).
Both of the types of hydraulic, inflatable devices have hollow cylinders that are implanted within the erection chambers of the penis. In order to create an erection, these inflatable devices use a pump to transfer fluid (saline) into the cylinders via tubing. As fluid is pumped into these cylinders, they expand to enlarge or "erect" the penis. The two and three-piece penile implants differ in their location of fluid storage, mainly how this fluid is then transferred out of the cylinders when an erection is no longer desired also is different.
- 2-piece inflatable implants - This is the simpler of the two types of inflatable device, accounting for approximately 15% of penile implants used worldwide. In the two-component penile prostheses, one component is the paired cylinders and the second component is the fluid-filled internal pump located inside the scrotum. Compression of the pump results in transfer of fluid from the back part of the cylinders and pump into the middle portion, resulting in rigidity. To end the erection with a two-component penile prosthesis, the penis is gently bent down for 5-10 seconds at its mid-shaft, resulting in the fluid being returned to the fluid-filled pump. The AMS 2-piece device (Ambicor), is the only currently available 2-piece. The advantage of this device is that it is easier to deflate and may be a better device for older men or men with poor manual dexterity. The disadvantage of this device is that in the flaccid state it always contains some fluid and thus the penis will always appear "full" (similar to the penile form after a man has a hot shower).
- 3-piece inflatable implants - The most commonly used inflatable device is the three-piece inflatable implant, accounting for approximately 75% of penile implants. This device has paired cylinders and a small scrotal pump, but in addition this device also has a fluid reservoir (which is placed behind the abdominal wall muscles) that is filled with saline solution. Thus, all parts of the device are internal. With these three-component devices, a larger volume of fluid is pumped into the cylinders for an erection by squeezing the concealed pump in the scrotum several times in order to move the fluid from this concealed reservoir into the cylinders that are in the penis. As the cylinders fill, the penis becomes erect and firm. When the erection is no longer desired, a release valve on the pump (in the scrotum) is simply pressed to transfer the fluid back into the reservoir and out from the cylinders, causing the penis to become flaccid. There are five different 3-piece devices available to address most implant situations. The advantage of a 3-piece device is that it is completely flaccid in the deflated state. It does however require some training to learn how to deflate the device.
One major difference between the hydraulic, inflatable prosthesis and the semi-rigid malleable penile implant is that the inflatable prosthesis has a more natural feeling since they allow for control of rigidity and size. The semi-rigid devices have the advantage of being the simplest of the penile implants and are the cheaper option. The disadvantages include a constantly rigid penis that resembles neither normal erection nor flaccidity, which makes it difficult to conceal under tighter fitting clothing as well as an increased risk for device erosion.
The pros and cons of each treatment option should be carefully discussed with the treating physician to make the best-informed choice and to ensure that the patient has realistic expectations about their treatment results.
What is involved in inserting a penile implant?
The surgical approach differs according to which implant is used, the history of the patient and the surgeon's preference. During surgery, which is done under anesthesia, the penile implant is inserted through an incision made in the penis, lower abdomen, or scrotum (depending on which type of penile device is being implanted). A thin, flexible tube is inserted briefly up the urethra and into the bladder to drain urine.
Usually one small surgical cut is made either above the penis where it joins the abdomen or under the penis where it joins the scrotum. In this procedure no tissue is removed and blood loss is usually small, therefore blood transfusions are almost never required. Patients may go home the same day of surgery or spend one night in the hospital. The operation takes approximately one hour to perform.
Most men have pain, some swelling and bruising after penile prosthesis implantation for about 2-4 weeks, for which oral pain medication is used and routinely helpful. Men are instructed not to use the prosthesis for sexual activity one month after surgery.
Neither the operation to implant a prosthesis, nor the device itself, should interfere with sensation, orgasm or ejaculation.
How effective are penile implants as a treatment for ED?
Long-term clinical data show that penile implants are highly effective and reliable, in fact about 90%-95% of inflatable prosthesis implants produce erections suitable for intercourse. Studies also find a very high degree of satisfaction by both users and their partners. Satisfaction rates with the prosthesis are typically 80%-90% and the vast majority of men say they would choose the surgery again. Studies indicate that men who undergo implant surgery report a dramatic improvement in erectile function for both non-inflatable and inflatable implants. Other research has found that satisfaction rates increase drastically after 6-12 months of use, with the most significant improvements reported in the second half of their first year following implant surgery.
Men using penile implants also report that erections created by implants seem more natural than ones from other, nonsurgical methods. They also say that penile implants offer spontaneity by allowing them to control when an erection will occur, as well as providing consistency, and rigidity.
Penile prostheses do increase hardness of the shaft of the penis, but that they do not routinely lengthen the penis.
What are the possible complications of penile implants?
The main risks are infection, erosion and mechanical failure. If infection occurs, removal of the prosthesis will most likely have to occur in order to eliminate the infection. Historically, after removing the prosthesis, re-implantation of another device has been postponed for several months.
Currently, salvage implant surgery removes the infected device and replaces it with a new device at the same time. The results of this approach suggest that 80% of the salvage implants do not get infected again. The advantage of this approach is that it avoids the penile shortening that occurs in the penis that has had an implant removed without being replaced.
Erosion, when the tissue around the implant is damaged and the device pushes through the skin, is often associated with infection and often necessitates removal of the device.
While post-operative complications of penile implant surgery are not common, mechanical failure is more likely to occur with inflatable than with rod prostheses. The most common cause of failure in these devices is leakage from the cylinders, causing the fluid present to leak into the body (these prostheses contain normal saline that is usually absorbed without harm). After mechanical failure, another operation for prosthesis replacement or repair is necessary if the man wants to remain sexually active. This occurs in 15-30% of men within 10-15 years after the original implant has been placed.
Other, less common mechanical complications include the implant being positioned incorrectly inflating spontaneously (auto-inflation).
When inserted, penile prosthesis does not change sensation on the skin of the penis or a man's ability to reach orgasm, and ejaculation is not affected. But, once a penile prosthesis is put in, it may destroy the ability to naturally get an erection.
As with all medical procedures, it is important to discuss the possible risks and complications involved in penile implant surgery with a physician in order to determine which procedure is best.
What is the cost of a penile implant?/ Will insurance cover this procedure?
The cost of penile implants (including device, medical procedure, and after-care) usually ranges from $15,000 - $20,000. The cost of treatment with healthcare coverage varies. However, insurance coverage for these operations is often good, since there is usually a medical cause of the ED. But, it is best to contact the individual provider in order to determine if urethral suppositories are covered by insurance and their individual cost to the patient.