Injectable semi rigid penile prosthesis: study in rabbits and future perspectives

Abstract

Background: Penile prostheses are the third option in the treatment of erectile dysfunction, however, despite their proven effectiveness, the occurrence of infections, advanced age of patients and comorbidities are the main limiting factors for this treatment modality. In the continuous search for biointegrated, clinically durable and minimally invasive treatment options, a possible model of penile prosthesis was sought through the use of intracavernous bacterial cellulose (BC) gel, in an experimental model of orchiectomized rabbits.Methods: Thirty adult New Zealand rabbits were equally distributed into three groups: BC; vehicle and control. Each group was then subdivided according to the follow-up time of 3 and 6 months.Bilateral orchiectomy was performed 3 weeks before injection in the BC and vehicle groups. Pachymetry measurements of the penile axis, diameter and length were performed in situ. Histomorphometry analyzes of the corpora cavernosa (CC), thickness of the tunica albuginea, cell density, collagen and elastic fibers postinjection were also performed, in addition to immunohistochemistry for newly formed vessels. Results:The implant of BC increased both the length and thickness of the penis three and six months after the last injection, with a consequent increase in the diameter of the CC. On the other hand, the filling effect was not observed in the control and vehicle groups, confirming the degradation of this tissue after orchiectomy and the effectiveness of BC as a filling agent. Histomorphometry analyzes corroborate the mass effect of BC integrated into the tissue, permeated by predominantly lymphomononuclear inflammatory infiltrate, multinucleated giant foreign body cells, fibroblasts, elastic fibers and newly formed vessels, without degradation or loss of volume, even after six months of implantation.Conclusions: Biocompatibility and biointegration to the host tissue make BC a prosperous penile filling material, with local application and minimally invasive.

Addressing the need for preclinical study of penile prosthesis infection: a new animal model and narrative review

“…Authors injected bacterial cellulose gel, which would act similarly to a malleable prosthesis but permit injection in lieu of surgical implantation, into the corpora cavernosa of 30 New Zealand White (NZW) rabbits. The study demonstrated gel biocompatibility and biointegration for 6 months ( 20 ). Four injections were performed within a 1-week interval, 3 weeks after bilateral orchiectomy to eliminate erectile function.…”

“…Four injections were performed within a 1-week interval, 3 weeks after bilateral orchiectomy to eliminate erectile function. Previous researchers had reported use of bacterial cellulose gel with sugarcane molasses substrate as a stable filling agent in several contexts outside ED; this gel leads to immediate erection from mass effect and eventual incorporation within host tissue ( 20 ).…”