Collagen periurethral injection is a procedure in which collagen is injected around the urethra and bladder neck as a treatment for stress incontinence in women.
The bladder and urethra are supported by muscles, ligaments, and connective tissues around the base of the bladder. This support prevents the leakage of urine, along with the watertight seal provided by the urethra. As a result of pregnancy, childbirth, and aging, or damage by scarring from surgery or radiotherapy, these structures may become damaged or weakened, thus causing stress incontinence, meaning an involuntary loss of urine that occurs during physical activity such as coughing, sneezing, laughing, or exercise .
The injection of bulking agents such as collagen around the urethra aims to improve the lost support of the bladder and urethra. The substance most commonly used for injection is collagen; other bulking agents are being developed, for example, a silicon base suspended in a viscous gel called Macroplastique. Teflon paste, introduced in the 1970s, initially gave good results, but was discontinued after reported problems with excessive scarring and with the migration of Teflon particles to other tissues in the body. The collagen used in the procedure comes from the cartilage of cattle and has been extensively sterilized to produce a viscous paste for injection. There is no risk of bovine spongiform encephalopathy (BSE) transmission because the processing of the paste destroys any bacterial or viral particles.
The collagen periurethral injection procedure is quick, and usually over within 15–20 minutes. No incisions are made, meaning that it can be carried out using a local anesthetic or a regional anesthetic such as an epidural. The surgeon uses a fine fiber-optic cystoscope to examine the inside of the urethra and bladder, and then inserts a fine needle to inject the collagen. Usually three injections are made around the urethra. The exact amount of collagen used depends on how much closure the urethra requires.
Since the procedure is very short and there is little discomfort afterwards, it is performed on an outpatient basis, and women can go home the same day. Recovery from the operation is very quick.
Periurethral injection is not associated with major complications. Urinary tract infection is common in up to a fifth of the women having undergone the procedure, but is usually quickly and easily treated with antibiotics . Some women experience difficulty urinating immediately after the procedure, but this is not unexpected following an operation involving the bladder and urethra that may easily lead to swelling and bruising of the tissues. It is a relatively uncommon problem after periurethral injection, but may occur. The condition usually settles quickly, but may require catheterization. Long-term problems are very rare.
Since periurethral injection is so quick and easy with very few complications, it would appear to be an ideal treatment for stress incontinence. However, there is a problem with the longer-term results. Within three months after injection, good results are reported with at least 80% of women cured or improved. However, after two years, less than half of these women will still be cured. Longer-term studies are still being performed, but it is likely that the results will keep becoming poorer as time goes by. This is due to the injected collagen dispersing away from the urethra over time. Injections can be repeated and some women do require more than one injection before they are cured. Ongoing research into newer injection substances may improve these results. The results in younger, physically active women are also less successful, usually lasting for a shorter time. Repeated injections are not the simple solution they may seem, because collagen is very expensive and the long-term effects of repeated injections are unknown. Physicians thus tend to prefer one of the alternative operations if long-term cure of stress incontinence is the aim.
Other treatments are available to treat incontinence. They include:
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National Association for Women's Health. 300 W. Adams Street, Suite 328, Chicago, IL 60606-5101. (312) 786-1468. http://www.nawh.org/ .
National Women's Health Information Center. http://www.4woman,org/ .
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"Stress Incontinence." MEDLINE Encyclopedia. http://www.nlm.nih.gov/medlineplus/ency/article/000891.htm .
Monique Laberge, Ph.D.
Collagen periurethral injection is a procedure that is performed in a hospital or clinic on an outpatient basis by a surgeon.