Fecal incontinence: New therapies, age-old problem

In most series, approximately 90% of patients have a positive test and progress to implantation. A recent US multicenter clinical trial indicated that 86% of patients achieved an improvement in continence of at least 50%, and 40% of patients were completely continent at 3 years.⁹ The number of episodes of incontinence decreased from a mean of 9.4/week to 1.7/week.⁹ Quality of life also improved greatly. Few complications have been reported, the most notable of which is infection (10.8% in the US multicenter trial⁹).

Another advantage of sacral neuromodulation: It can be used successfully in patients with external sphincter defects as large as 120º. A study by Tjandra and colleagues found that 65% of patients experienced improvement in symptoms of at least 50%, and 47% of patients (more than 50% of whom had external sphincter defects as large as 120º) became completely continent.¹⁰

The only variable shown to predict success with sacral neuromodulation is a positive response to the test implant procedure.

In our experience, this procedure is easy to perform and well tolerated, even in elderly patients with multiple comorbidities. The procedure has the additional advantage of potentially improving concomitant urinary symptoms as well.

The major disadvantage of sacral neuromodulation is its cost, although most major insurance carriers cover it. There is no well-conducted cost-effectiveness analysis comparing this modality to other treatments.

Related Article Interstim: An implantable device for implacable urinary symptoms Deborah L. Myers, MD (October 2006)

Injectable agents
Several biocompatible bulking agents have been tested in the treatment of fecal incontinence. These compounds traditionally have been used to treat mild fecal incontinence, or to treat patients with isolated internal sphincter defects.
More recently, an injectable dextranomer in stabilized hyaluronic acid was approved by the FDA and marketed as Solesta. Graf and colleagues randomly allocated 136 patients to injection and 70 patients to sham injection. Patients with external sphincter defects were excluded. At 6 months, 52% of patients in the active treatment group experienced an improvement in continence of at least 50%, compared with 31% of patients injected with placebo.¹¹

The advantage of this procedure is its minimally invasive nature (submucosal injection performed in the office). The disadvantage: a lack of long-term efficacy data, although unpublished data suggest that patients who improve after an injection see a durable response at 3 years.

This easy, office-based treatment is ideal for patients with minor incontinence or persistent symptoms after another procedure.

Sphincter repair
Anterior sphincteroplasty has been the mainstay of surgical treatment for patients with a sphincter defect. With the patient in a dorsal lithotomy or prone position on the ­operating-room table, a transverse perineal incision is made, and the ends of the severed sphincter muscle are located and mobilized. The repair then can be performed in an end-to-end manner or by overlapping the muscles in the anterior midline (FIGURE 4).

Some of the debatable technical issues of this procedure include:

• whether to overlap the muscles or scar tissue
• whether to repair internal and external defects together or separately
• how the age of the patient affects the outcome.

In regard to the first issue, there may be a superior outcome with overlapping repairs, but they carry a higher risk of dyspareunia and evacuation difficulties. Some surgeons will attempt a separate repair of the internal and external sphincter muscles if it appears feasible. Most often, both muscles are ­tethered together with scar tissue and separate repair is not possible. There are no conclusive data to demonstrate the superiority of either approach.

As for age, the traditional teaching was that older patients do not benefit from this procedure as much as younger patients do. However, a recent study found no differences in the CCF-FIS score in patients older than age 60, compared with younger patients.¹² Investigators concluded that sphincteroplasty can be offered to both young and older ­patients.¹²

Although sphincteroplasty often leads to excellent short-term improvement, with 60% to 90% of patients experiencing a good or excellent outcome, nearly all series indicate a decline over the long term (>5 years). A recent systematic review found that as few as 12% of patients experience a good or excellent result, depending on the series.¹³

We offer sphincter repair to young women with a new sphincter defect after delivery. For older patients, we offer sacral neuromodulation as a first-line treatment.

Other surgical options
We believe that most patients with fecal incontinence can be managed using conservative measures, sacral neuromodulation, injectable dextranomer, or sphincter repair. However, several other options are available.

Artificial bowel sphincter
The artificial bowel sphincter was first described in 1987 and has been modified over the years. The system currently is marketed as the Acticon Neosphincter (American Medical Systems, Minnetonka, Minnesota). The procedure involves the creation of a subcutaneous tunnel around the anus so that an inflatable cuff can be positioned there. A pump then is tunneled through a Pfannenstiel incision to the labia or scrotum, and a reservoir is positioned in the space of Retzius. The device maintains continence by keeping the cuff inflated during the resting state and by pumping fluid from the cuff to the reservoir when the patient needs to evacuate.