Retrospective analysis after endoscopic urethral injections of glutaraldehyde‐cross‐linked‐collagen or dextranomer/hyaluronic acid copolymer in bitches with urinary incontinence

OBJECTIVES To evaluate the outcome of endoscopic injection of two different bulking agents, glutaraldehyde cross-linked collagen and dextranomer/hyaluronic acid copolymer into the urethral submucosa in female dogs with urinary incontinence caused by urethral sphincter mechanism incompetence. MATERIALS AND METHODS Retrospective review of records and follow-up communication with owners of dogs that received an endoscopically guided urethral bulking procedure. In each dog, either cross-linked collagen (2007 to 2011) or dextranomer/hyaluronic acid copolymer (2012 to 2015) was used. At least three injections were made in a circular arrangement in the midurethral region until the urethral lumen was closed. RESULTS Complete questionnaires were available from 50 of 100 pet owners. The mean interval between the treatment and interview was 67 (range: 57 to 114) months in the cross-linked collagen group and 19 (range: 2 to 48) months in the dextranomer/hyaluronic acid copolymer group. The mean duration of continence was 45∙8 months (range: 12 to 84 months) in the cross-linked collagen group and 20∙5 months (range: 12 to 48 months) in the dextranomer/hyaluronic acid copolymer group. The success rate at 6 months or more after the procedure was 71% after the injection of cross-linked collagen and 58% after injection of dextranomer/hyaluronic acid copolymer. One minor complication (transient haematuria) occurred in one dog. There were no major complications. CLINICAL SIGNIFICANCE Urethral injection of dextranomer/hyaluronic acid copolymer in bitches with urethral sphincter mechanism incompetence is a useful alternative to cross-linked collagen injection, which is no longer available in the European market. Dextranomer/hyaluronic acid copolymer injection is a minimally invasive alternative to surgical procedures and has a low complication rate.