How does an erection work with a penile implant?
With an inflatable implant, an erection is produced by pressing a pump in the scrotum, which fills two cylinders in the penis with fluid until the shaft is firm, and a release mechanism ends it. A semi-rigid implant stays firm and is bent upward by hand. Satisfaction with implant surgery reaches 92% to 100% in patients and 91% to 95% in partners.
How is an erection produced with an inflatable implant?
An inflatable implant holds fluid in a reservoir in the lower abdomen or, in a two-piece design, within the device itself. Pressing the pump in the scrotum moves fluid into the cylinders inside the penis, and the shaft becomes firm. A release mechanism returns the fluid when the erection is no longer wanted.
The erection lasts as long as the man wants and can be produced as often as he wants. Before surgery, men are counselled on how long healing usually takes before the device can be used safely, and the steps of operating the pump are demonstrated to the man and his partner.
How is a semi-rigid implant positioned?
A semi-rigid implant has no pump or fluid. The penis stays firm at all times and is bent upward for intercourse and downward to lie against the groin at other times, and the implant cannot be deflated. The operation is simpler and the device is easy to use.
The trade-off is a penis that stays permanently firm and is harder to conceal. Satisfaction is generally higher with inflatable devices, but a semi-rigid implant can be more appropriate for men with limited hand dexterity or when cost is a concern.
How does an implant erection differ from a natural one?
An implant makes the shaft rigid, but the glans, or head of the penis, does not usually become rigid or swell. The lack of glans swelling is one reason the penis can look shorter during an implant erection than during a natural erection before surgery.
"One element of setting appropriate expectations is explaining the differences between the inflatable and malleable devices in terms of the ease of operation, appearance, and concealability of the device." Source 2, p. 32
Some men also feel the penis is shorter when the implant is inflated than it was during a full erection before surgery. Desire is not directly changed by an implant, and neither orgasm nor ejaculation is enhanced. Men who discuss these points before surgery and hold realistic expectations report higher satisfaction afterwards.
How reliable is an implant erection over the years?
A meta-analysis found that 87.2% of implants were still working at five years, 76.8% at ten years and 52.9% at twenty years. Mechanical failure is most common with inflatable models and usually comes from a leak in the connecting tubing, and the most commonly used three-piece devices show failure rates below 5% after five years.
Infection is the other main complication. It affects 2% to 3% of men after a first implant in low-risk patients at high-volume centres and usually means removing the device.