Artificial Sphincter Implants

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.

Purpose

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.


This includes conditions that result in the removal of the sphincter. Sphincter deficiency can result directly from pelvic fracture; urethral reconstruction; prostate surgeries; spinal cord injury; neurogenic bladder conditions that include sphincter dysfunction; and some congential conditions. Each can warrant consideration for a sphincter implant.


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

Fecal incontinence is the inability to control bowel function. The condition can be the result of a difficult childbirth, colorectal disease such as Crohn’s disease, accidents involving neurological injuries, surgical resection for localized cancer, or by other neurological disorders. Severe fecal incontinence may, depending upon the underlying disease, require surgical intervention that can include repair of the anal sphincter, colostomy , or replacement of the anal sphincter. Artificial anal sphincter is a very easy-to-use device implanted under the skin that mimics the function of the anal sphincter.

Description

Artificial urinary sphincter surgery


The artificial urinary sphincter is an implantable device that has three components:


an inflatable cuff
a fluid reservoir (balloon)
a semiautomatic pump that connects the cuff and balloon
Open surgery is the major form of surgery for the implant. Infections are minimized by sterilization of the urine preoperatively and preoperative bowel preparation. The pelvic space is entered from the abdomen or from the vagina, with general anesthesia for the patient. Broad-spectrum antibiotics are given intravenously and at the site of small incisions for the device. A urinary catheter is put into place. The cuff is implanted around the bladder neck and secured and passed through the rectus muscle and anterior fascia to be connected later to the pump. A space is fashioned to hold the balloon in the pubic region, and a pump is placed in a pouch below the abdomen. The artificial urinary sphincter is activated only after six to eight weeks to allow healing from the surgery. The patient is trained in the use of the device by understanding that the cuff remains inflated in its “”resting state,”” and keeps the urethra closed by pressure, allowing continence. Upon the decision to urinate, the patient temporarily deflates the cuff by pressing the pump. The urethra opens and the bladder empties. The cuff closes automatically.

Artificial sphincter

Artificial anal sphincter surgery


The artificial anal sphincter is an implantable device that has three components:


an inflatable cuff
a fluid reservoir (balloon)
a semiautomatic pump that connects the cuff and balloon
In open abdominal surgery, the implant device is placed beneath the skin through small incisions within the pelvic space. One incision is placed between the anus and the vagina or scrotum, and the inflatable cuff is put around the neck of the anal sphincter. A second incision at the lower end of the abdomen is used to make a space behind the pubic bone for placement of the balloon. The pump is placed in a small pocket beneath the labia or scrotum, using two incisions. The artificial anal sphincter is activated only after six to eight weeks to allow healing from the surgery. The patient is trained in the use of the device by understanding that the anal cuff remains inflated in its “”resting state,”” and keeps the anal canal closed by pressure, allowing continence. Upon the decision to have a bowel movement, the patient temporarily deflates the cuff by pressing the pump and fecal matter is released. The balloon re-inflates after the movement.