Pseudo-capsule "coffin effect": how to prevent penile retraction after implant of three-piece inflatable prosthesis.

OBJECTIVE: Following three-component implantation of a penile prosthesis, some patients are dissatisfied with their penile length. This may be due to the procedure by itself or pre-existing risk factors or psychological reasons. We supposed that formation of a restricted pseudo-capsule due to a late prosthesis activation can inhibit later system expansion. We aimed to identify the presence or absence of penile retraction after implant and to prevent it by immediate prosthesis activation after implantation.

MATERIAL AND METHODS: Forty-six patients operated with three-piece inflatable penile prosthesis (AMS 700 CX o LGX) were enrolled. In 27 patients prosthesis was first activated four weeks after surgery (NEA group) and in 19 patients prosthesis was activated immediately after surgery (DEA group). Length and girth of the penis was evaluated before (in DEA group) and after the surgical procedure.

RESULTS: The average post implant dorsal length of the erect penis in group NEA was found 3.28 cm shorter than in group with early activation (DEA). In DEA group there was no lenght difference between pre-operative stretching (14.57 cm) and post operative erection (14.98 cm). When early activation was not performed, the clinical result was a smaller penis in erect phase.

CONCLUSION: Reduced lenght of the penis after implantation can be caused by the presence of a pseudo-capsule that limits the elongation of the prosthesis and of the penis ("coffin effect"). Timing of first activation seems to be the key in order to prevent the risk of penile retraction after implantation. Early activation is identified as the best measure to maintain the length of the pre implant erect penis after the prosthetic hydraulic implant.