Mechanical indications for inflatable penile prosthesis revision: analysis and implications for revision surgery

Abstract

Background: Despite technical advancements, inflatable penile prostheses (IPPs) are inherently at risk of mechanical failure given their nature as hydraulic devices.

Aim: To characterize IPP component failure location at the time of device revision and stratify by manufacturer: American Medical Systems (Boston Scientific [BSCI]) and Coloplast (CP).

Methods: A retrospective review of penile prosthesis cases from July 2007 to May 2022 was conducted, identifying men who underwent revision surgery. Cases were excluded if documentation did not denote the cause of failure or the manufacturer. Mechanical indications for surgery were categorized by location (eg, tubing, cylinder, or reservoir leak; pump malfunction). Nonmechanical revisions were excluded (component herniation, erosion, or crossover). Categorical variables were assessed with Fisher exact or chi-square analysis; Student t-test and Mann-Whitney U test were used for continuous variables.

Outcomes: Primary outcomes included specific location of IPP mechanical failure among BSCI and CP devices and time to mechanical failure.

Results: We identified 276 revision procedures, 68 of which met inclusion criteria (46 BSCI and 22 CP). Revised CP devices were longer than BSCI devices (median cylinder length, 20 vs 18 cm; P < .001). Log-rank analysis revealed a similar time to mechanical failure between brands (P = .096). CP devices failed most often due to tubing fracture (19/22, 83%). BSCI devices had no predominant site of failure. Between manufacturers, tubing failure was more common in CP devices (19/22 vs 15/46 for BSCI, P < .001), while cylinder failure was more common among BSCI devices (10/46 vs 0/22 for CP, P = .026).

Clinical implications: The distribution of mechanical failure is significantly different between BSCI and CP devices; this has implications regarding the approach to revision surgery.

Strengths and limitations: This is the first study to directly compare when and where mechanical failure occurs in IPPs and to compare the 2 main manufacturers head-to-head. This study would be strengthened by being repeated in a multi-institutional fashion to provide more robust and objective evaluation.

Conclusion: CP devices commonly failed at the tubing and rarely elsewhere, while BSCI devices showed no predominant failure site; these findings may inform decision making regarding revision surgery.

Keywords: penile implant; penile prosthesis; prosthesis failure; prosthesis survival.