Perianal injection of polydimethylsiloxane (Bioplastique implants) paste in the treatment of soiling: pilot study in rats to determine migratory tendency and locoregional reaction

Not much is known about the specific pathophysiologic mechanisms of soiling. Although the causes of soiling may vary, it is mostly associated with anorectal disorders that can deform the contour of the anus and anal canal. In most cases, this disorder can be treated successfully by medical or surgical therapy. If this appropriate treatment is not available or fails, reconstruction of the contour deformity of the anus by perianal (submucosal) injection of soft tissue bulking agents may be successful. The main purpose of this pilot study was to evaluate locoregional reaction and distant migration after local perianal injection of solid polydimethylsiloxane elastomer particles (Bioplastique implants). Twelve Lewis rats received a local perianal injection of Bioplastique implants. Six of them received an additional perianal injection of gentamicin. Six weeks after injection, the rats were euthanized. Microscopically, the local tissue reaction was that of a quiescent foreign body reacting with encapsulation. Microscopic examinations could not reveal any migration to locoregional lymph nodes, liver, spleen, lungs, or brain. We conclude that, because of minimum local reaction and lack of evidence of distant migration, polydimethylsiloxane elastomer particle paste (Bioplastique implants) seems to be a potentially safe substance for local perianal injection