Penile prostheses are divided into 3 general types: malleable (semirigid), mechanical, and inflatable devices. The malleable devices are made of silicone rubber and several models contain a central intertwined metallic core. The mechanical device is also made of silicone rubber but contains polytetrafluoroethylene-coated interlocking polysulfone rings in a rod column, which provides rigidity when the rings are lined up in a straight line and flaccidity when the penis is bent.

Inflatable (hydraulic) devices are further divided into 2-piece and 3-piece devices. Two-piece inflatable prostheses consist of a pair of cylinders attached to a scrotal pump-reservoir. Three-piece inflatable penile prostheses consist of paired the penile cylinders, a scrotal pump, and a suprapubic fluid reservoir (

Table 37-6).

In general, the malleable devices last longer than the inflatable ones. Patients should be informed that a 5-15% failure rate is expected in the first 5 years and most of the devices will fail in 10-15 years and will need a replacement. Potential complications include mechanical failures, cylinder leaks, tubing leaks, infection, perforation, persistent pain, and autoinflation (_{Mulcahy, 2000; Montague et al, 2001; Anastasiadis et al, 2001}).