Periurethral Collagen Injection for Stress Incontinence With and Without Urethral Hypermobility

Abstract

Urethral bulking for female stress urinary incontinence using bovine collagen is an accepted method of controlling urinary incontinence. Its use is currently recommended for women whose stress incontinence is caused by intrinsic sphincter deficiency without urethral hypermobility, but it is not generally recommended for women with urethral hypermobility. This article presents the results of a retrospective review of 40 women, with and without urethral hypermobility, who were treated for stress urinary incontinence with periurethral injections over a 1-year period. All patients underwent a complete urodynamic examination. A change of more than 30 degrees from rest to maximum Valsalva on the cotton swab test was defined as urethral hypermobility. Patients with intrinsic sphincter deficiency were offered collagen therapy if their maximum urethral closure pressure was 20 cm H2O or less and/or if their Valsalva leak-point pressure measured less than 60 cm H2O. An immobile urethra, severe stress incontinence, previous antiincontinence surgery, or other contraindications to more expensive surgical procedures were also indications for collagen therapy. With the aid of a cystoscope, glutaraldehyde cross-linked collagen (Contigen, C. R. Bard, Inc., Covington, GA) was injected periurethrally with a 22-gauge spinal needle in the tissue just lateral to the proximal urethra and bladder neck. Postprocedure care included intermittent self-catheterization until postvoid residual was less than 25 percent of bladder capacity. Antibiotics were administered for at least 1 day or as long as self-catheterization continued. Nine of the 40 study patients (23 percent) had urethral hypermobility. The average change from rest to maximum Valsalva during the cotton swab test was 43 degrees for women with urethral hypermobility, compared with 6 degrees for those without hypermobility (P < .001). Otherwise, both patient groups were comparable. A total of 60 collagen injections were given to the 40 women over the 1-year study period. The average length of follow-up was 8.3 months. One woman (without hypermobility) dropped out of the study after the first collagen injection because of discomfort. In the remaining women, follow-up examinations were performed 1 (N = 39) and 6 months (N = 25) after the procedure. The subjective rates of dryness (76 percent of those with hypermobility and 46 percent of those without hypermobility), number of collagen injections (1.9 and 1.4, respectively) or amount of collagen required (5.6 and 5.3 ml, respectively), and reported overall satisfaction rate (3.0 and 2.0, respectively, on a scale of 1 to 3, with 3 being complete satisfaction) were similar for both groups of women at the 1-month follow-up examination. At the 6-month examination, the subjective dryness rates had fallen slightly (71 for those with hypermobility and 32 for those without hypermobility), and the reported overall satisfaction rate dropped to 2.0 for the women without, but remained at 2.0 for those with, urethral hypermobility. Again, these differences were not statistically significant. Two patients in the group with urethral hypermobility experienced complications. An unexplained low-grade fever developed in one woman after injection and was thought to be a reaction to collagen. Another patient, who had undergone a failed suburethral sling procedure, had four injections during this study and several more at another facility and developed a urethral-vaginal fistula. Approximately half of the women in each group reported some de novo bladder overactivity after the procedure. More women with hypermobility (38 percent) than without it (24 percent) developed at least one urinary tract infection, but the difference was not significant. Obstet Gynecol 2000;95:327–331