Up to one fourth of women between 15 and 60 years of age report symptoms of urinary incontinence. In most, incontinence results from a lack of support of the vesicourethral junction. Another major cause of stress incontinence is intrinsic sphincter deficiency caused by trauma, surgical injury, sympathetic nerve dysfunction or myelodysplasia. Conventional surgical treatments of intrinsic sphincter deficiency may result in detrusor problems leading to urinary retention, manifested as frequency, urgency and urge incontinence. Koelbl and colleagues assessed the short-term efficacy of transurethral injection of silicone microimplants in women with intrinsic sphincter deficiency.

Thirty-two women (median age: 64.3 years) who had intrinsic sphincter deficiency as the cause of stress incontinence were enrolled in the study. Twenty-eight of these women had undergone previous surgical procedures: 18 women had had one surgical intervention, and 10 had two previous surgeries for incontinence. Each woman underwent a comprehensive urogynecologic assessment before transurethral injection of silicone microimplants. The implants were placed under direct vision at 2-, 6- and 10-o'clock positions, 2 cm distal to the bladder neck. Each woman underwent full clinical and urogynecologic review after six and 12 months.

Immediately following surgery, all 32 patients reported continence of urine; urodynamic measurements validated the subjective reports. After six months, 24 patients (75 percent) still reported continence, validated by measurements. By 12 months, 19 women (59 percent) reported continence. For the entire group, the injections significantly increased maximal urethral closing pressures. Two patients developed urinary tract infections following surgery, and two patients required sling procedures three months after the injections failed. No other complications were noted during the study.

The authors conclude that this relatively simple new technique can provide complete resolution of incontinence. After 12 months, approximately 60 percent of patients in this study were subjectively and objectively continent. Although the benefit of the procedure may decrease over time, the authors believe it will provide a good treatment option, particularly in the elderly or in those patients who are unfit for major surgery.