Artificial Sphincter Insertion
Artificial sphincter insertion surgery is the implantation of an artificial valve in the genitourinary tract or in the anal canal to restore continence and psychological well being to individuals with urinary or anal sphincter insufficiency that leads to severe urinary or fecal incontinence.
This procedure is useful for adults and children who have severe incontinence due to lack of muscle contraction by either the urethral sphincter or the bowel sphincter. The primary work of the lower urinary tract and the colon is the storage of urine and waste, respectively, until such time as the expulsion of urine or feces is appropriate. These holding and expelling functions in each system require a delicate balance of tension and relaxation of muscles, especially those related to conscious control of the act of urination or defecation through the valve-like sphincter in each system. Both types of incontinence have mechanical causes related to reservoir adequacy and sphincter, or "gatekeeper" control, as well as mixed etiologies in the chemistry, neurology, and psychology of human makeup. The simplest bases of incontinence lie in the mechanical components of reservoir mobility and sphincter muscle tone. These two factors receive the most surgical attention for both urinary and fecal incontinence.
Urinary sphincter surgery
There are four sources of urinary incontinence related primarily to issues of tone in pelvic, urethral, and sphincter muscles. Most urinary incontinence is caused by leakage when stress is applied to the abdominal muscles by coughing, sneezing, or exercising. Stress incontinence results from reduced sphincter adequacy in the ability to keep the bladder closed during movement. Stress incontinence can also be related to the mobility of the urethra and whether this reservoir for urine tilts, causing spilling of urine. The urethral cause of stress incontinence is treated with other surgical procedures. A second form of incontinence is urge incontinence. It relates to sphincter overactivity, or sphincter hyperflexia, in which the sphincter contracts uncontrollably, causing the patient to urinate, often many times a day. Finally, there is urinary incontinence due to an inadequately small urethra that causes urine overflow. This is known as overflow incontinence and can often be treated with augmentation to the urethra to increase its size.
Only severe stress incontinence related to sphincter adequacy can benefit from the artificial urinary sphincter.
Implantation surgery related to urinary sphincter incompetence is also called artificial sphincter insertion or inflatable sphincter insertion. The artificial urinary sphincter (AUS) is a small device placed under the skin that keeps pressure on the urethra until there is a decision to urinate, at which point a pump allows the urethra to open and urination commences. Since the 1990s, advances in prostate cancer diagnosis and surgery have resulted in radical prostatectomies being performed, with urinary incontinence rates ranging from 3–60%. The AUS has become a reliable treatment for this main source of urinary incontinence in men. Women with intrinsic sphincter deficiency, or weakened muscles of the sphincter, also benefit from the AUS. However, the use of AUS with women has declined with advances in the use of the sub-urethral sling due to its useful "hammock" effect on the sphincter and its high rates of continence success. Women with neurologenic incontinence can benefit from the AUS.
Artificial anal sphincter surgery
Milder forms of fecal incontinence are being treated by changes in diet and the use of certain bowel-binding medications. For some forms of mild fecal incontinence, special forms of exercise can help to strengthen and tone the pelvic floor muscles, along with providing biofeedback to train the muscles to work with an appropriate schedule. Only after these measures have been tried, including the use of pads, is the patient counseled on the benefits of an anal sphincter implant.
Artificial urinary sphincter surgery
Milder forms of urinary incompetence can be treated with changes in diet, evaluation of medications, and the use of antidepressants and estrogen replacement, as well as bladder training and pelvic muscle strengthening. However, sphincter deficiency, unlike incontinence caused by urethral mobility, requires a substitute for the sphincter contraction by implant or by auxiliary tissue. If AUS cannot treat sphincter deficiency, the sling or "hammock" procedure is a good second choice. It brings tightness to the sphincter by using tissue under the urethra to increase contractual function. The sling procedure is already preferred over the AUS for women.
Walsh, P., et al. Campbell's Urology, 8th Edition. St. Louis: Elsevier Science, 2000.
Michot, F. "Artificial Anal Sphincter in Severe Fecal Incontinence: Outcome of Prospective Experience with 37 Patients in One Institution." Annals of Surgery, Vol. 237, No. 1 (January 1, 2003): 52–56.
Rotholtz, N. A., and S. D. Wexner. "Surgical Treatment of Constipation and Fecal Incontinence." Gastroenterology Clinics, Vol. 30, No. 01 (March 2001).
American Society of Colon and Rectal Surgeons. 85 W. Algonquin Rd., Suite 550, Arlington Heights, IL 60005. <www.fascrs.org.>.
National Institute of Diabetes and Digestive and Kidney Diseases. (800) 891-5390 (kidney); (800) 860-8747 (diabetes); (800) 891-5389 (digestive diseases). <www.niddk.nih.gov.>.
National Association of Incontinence. <www.nafc.org.>.
Fecal Incontinence. National Institute of Diabetes & Digestive & Kidney Diseases (NIDDK). <www.niddk.nih.gov/health/digest/pubs/fecalincon/fecalincon.htm>.
Incontinence in Men. Health and Age. <http://www.healthand age.com.>.
Urinary Incontinence. WebMD Patient Handout. <www.MD-consult.com.>.
Urinary Incontinence in Women. National Institute of Diabetes & Digestive & Kidney Diseases (NIDDK). <www.niddk.nih.gov/health/urolog/pubs/uiwomen/uiwomen.htm.>.
Nancy McKenzie, PhD
WHO PERFORMS THE PROCEDURE AND WHERE IS IT PERFORMED?
Implantation surgery is performed in a hospital operating room by urologic surgeons specially trained for implantation of the artificial sphincter in the urinary or anal tracts. Successful surgery depends upon very experienced surgeons.
QUESTIONS TO ASK THE DOCTOR
- How many implantation surgeries have you performed?
- What is your rate of device removal in the patients you have treated?
- How likely is infection after surgery?
- How likely is infection to occur long term?