Fecal Incontinence - A Practical Approach

Steve Wexner

Powerpoint File

Introduction:
Fecal incontinence (FI) is usually defined as the involuntary loss of bowel control, which normally allows the passage of gas or stool at a socially acceptable time and place. Normal continence results from an integrated activity of the anal sphincters, pelvic floor muscles and adequate neural input. It is also influenced by stool consistency, rectal capacity and compliance, the anorectal sampling reflex, normal resting anal tone and normal anorectal sensation. Failure of any of those factors may result in FI.
The true incidence and prevalence of FI are unknown; a recent meta-analysis reported rates ranging from 11% to 15% (1).
When planning a treatment regimen, it is extremely important to make the subjective complaints and symptoms of FI somewhat more objective. To accomplish that goal, several scoring systems have been designed and validated, including the Cleveland Clinic Florida FI (CCF-FI; Wexner) score (2).

As to which surgical modality should be undertaken is usually clear depending on the integrity of the anal sphincters. Patients with obvious sphincter defects should normally undergo an overlapping sphincteroplasty; alternatively, other modalities should be pursued in patients with intact sphincters.
Novel surgical modalities for fecal incontinence;

Injectable bulking agents: The concept has been adapted from the field of urology where it has been used for decades. Shafik provided the first report of successful short-term outcomes of treatment of FI with submucosal injection of polytetrafluoroethylene (Teflon® or Polytef; DuPont, Wilmington, DE) in 1993 (3), and similar outcomes with the use of autologous fat in 1995 (4). Additional materials that have been used as bulking agents for the anal sphincters with varying degrees of success include GAX (glutaraldehyde cross-linked collagen) and injectable-silicone. Carbon-coated beads are another compound that initially has been used as a bulking agent for treating urinary incontinence and recently applied for FI as well under the trade name DurasphereÒ FI (formerly known as ACYSTÔ - Carbon Medical Technologies, Inc. St. Paul, MN, distributed by Boston Scientific Corporation, Boston MA). Weiss et al. (5) from Cleveland Clinic Florida presented their experience with DurasphereÒ FI. Ten patients (7 females) with severe FI were enrolled in a prospective, open-label pilot trial. DurasphereÒ FI was injected in the submucosal space 0.5-1cm distal to the dentate line, typically 45 degrees apart. Eight of the 10 patients (80%) experienced symptomatic improvement. The CCF-FI score decreased from an average of 13 at baseline to 10 at 3 months after the injection (p=0.012), and to 9.3 after 6 months. A large prospective, randomized multi-center trial in the US was concluded recently and its results are pending.

Radiofrequency – RF; the SECCA® procedure:

The radiofrequency (RF) device deploys energy by generating heat through a high frequency, alternating current that is delivered to the tissue, causing frictional movement of ions and heat. The immediate result is contraction of collagen fibers, with subsequent healing and remodeling processes that cause shortening of the fibers and tightening of the tissue. The Secca® procedure (formerly produced by Curon Medical, Sunnyvale, CA) was approved by the FDA in March 2002 for the treatment of FI. The procedure is typically performed at an ambulatory setting, during which the RF energy is delivered to the anal canal with the specialized device. Takahashi et al. reported the results of the first trial that assessed the efficacy of the procedure for treating FI (6) with a subsequent report of the results at two-year follow-up (7). The investigators treated 10 female patients with the Secca® procedure and observed a significant reduction in the CCF-FI score from 13.5 at baseline to 5 after 12 months (p<0.001); the average CCF-FI score after 2 years was 7.3 (p=0.002) which further emphasizes the procedure’s long-term durability. Efron et al. treated 50 patients with the Secca® procedure in a multicenter trial in the United States (8). The average CCF-FI score decreased from 14.5 at baseline to 11.1 after 6 months (p<0.0001). Again, in both studies a significant improvement in quality of life was demonstrated as well. A multi-institutional, single-blinded, randomized, prospective trial comparing the Secca® procedure to a sham intervention has been recently completed and its results are pending.

Artificial Bowel sphincter – ABS: Another concept that was adapted from the field of Urology is the use of synthetic material to replace a malfunctioning sphincter. The Acticon® Neosphincter (American Medical Systems, Minnetonka, MN) was approved by the FDA for the treatment of FI in 1999. The largest case series to date that assessed its safety and efficacy was reported by Wong et al. in 2002 (9). One hundred twelve patients were enrolled in a prospective, multicenter, non-randomized cohort trial. At one-year follow-up, 75 of these 112 patients (67%) had a functional device; of these, 85% had significant improvement in incontinence scores and quality of life parameters. The overall intention to treat success rate was 53%. Ninety-nine patients (88%) had a total of 384 complications related to the ABS; forty-one patients (37%) had their ABS completely explanted, and the overall infection rate that led to surgical interventions was 25%. A systematic review of the literature about ABS (10) demonstrated that approximately one-third of the patients have their ABS explanted by the end of the follow-up period; this number approaches 50% in series with the longest follow-up (5 years), which may be an indirect indicator of the lifespan of the device. There are no reported data on the outcomes of the patients in whom the ABS was explanted. Since these patients represent a substantial percentage of all those treated by ABS, and the condition of these patients may have deteriorated following the explantation, these data may be crucial to fully appreciate the true efficacy and safety of the device.

Stimulated Graciloplasty:
Any skeletal muscle considered as a potential candidate for replacing the anal sphincter should have a relatively negligible role in movement or posture; should be large enough to provide sufficient bulk and should have a neurovascular pedicle(s) that will allow simple handling in the process of mobilization and transposition. The gracilis muscle is the smallest and most superficial adductor of the thigh. It has a relatively consistent proximal neurovascular pedicle and it has an insignificant role in movement. The Dynamic Graciloplasty Therapy Study Group conducted the largest, prospective, multi-national trial that assessed this procedure and produced both short-term and long-term data (11,12). In the initial report, 60% of the patients had significant improvement in continence and quality of life; the long-term durability of the procedure was demonstrated by showing that at 2-year follow-up, 62% of the patients had significant improvement in continence and quality of life parameters. Nevertheless, stimulated graciloplasty is very technically demanding with considerable morbidity. This procedure is not able to be performed in the US because the company sadly never pursued FDA approval or CMSs reimbursement.

Sacral Nerve Stimulation – SNS:
Once again the concept was initially implemented for treating urinary incontinence, and subsequently the technology has been adopted by the colorectal community as well. Matzel et al. (13) published the first report of successful outcomes in 3 patients who were treated with SNS in 1995; in the last decade since that initial report, several hundreds of patients have been treated with SNS for FI in Europe; In the US, SNS was assessed in a multi-center trial and its result are pending. The rationale behind SNS is that direct stimulation of the sacral nerves potentially will result in recruitment and arousing of additional, inactive motor units. SNS also has a beneficial effect on the sensory and autonomic components of the sacral nerves as demonstrated by improvement in rectal sensory threshold and improved balloon expulsion time, and an increase in the resting anal pressure, and rectal blood flow. The technique of SNS is unique in the sense that it includes an extremely strict patient selection process which is an integral part of the procedure sequence itself. This selection process allows choosing patients with the best potential to benefit from the procedure. A recent systematic review of SNS for the treatment of FI (14) evaluated 6 studies. A total of 266 patients underwent initial evaluation of whom 149 (56%) had a permanent stimulator implanted; follow-up periods ranged from 1 to 99 months. Complete continence was reported in approximately 55% of patients, with 90% having over 50% improvement in incontinence; there was no deterioration of the effect of SNS over time. The reported complications were minor and rare with lead migration being the most common accounting for 8 of the 19 adverse events, and infection necessitating explantation of the stimulator occurred in 3 patients; the remaining complications were attributed mostly to pain originating either in the stimulator or leads.

Choice of procedure:

Patients in poor general health with significant comorbidities who are suboptimal surgical candidates and individuals who refuse more invasive therapy, may benefit most from the least invasive procedure which is injection of a bulking agent. The Secca® procedure and SNS are also considered relatively minimally invasive but they are performed in a monitored setting, under some form of anesthesia and require sophisticated instrumentation. Another patient-related aspect which needs to be addressed when planning a surgical intervention is the patient’s mental capacity. ABS, SNS and stimulated graciloplasty all are extremely high-maintenance procedures that mandate that the patients have complete appreciation of the complexity of the hardware, basic knowledge in pelvic and anorectal anatomy and full commitment to daily operation and maintenance of the devices; they should also be educated as to the high rates of complications, be able to recognize the early signs of failure, and be mentally prepared for re-operations including the possibility of a need for a stoma. Conversely, injectable bulking agents and RF do not require any maintenance or routine follow up thus may be more suitable for patients with impaired mental capacity; however, the treatment may need to be repeated at periodic intervals. Injectable bulking agents, the Secca® procedure, stimulated graciloplasty and ABS implantation require direct manipulation of the perianal area, anal canal or distal rectum. Consequently, any local pathology – abscesses, fistulae, fissures, perianal inflammatory bowel disease or anorectal cancer, all are contraindications for attempting these modalities. Patients with cardiac pacemakers or implantable defibrillators should not undergo SNS or the stimulated graciloplasty because of the obvious interference of the electrical stimulators. The artificial bowel sphincter has been implanted in patients with preexisting urinary sphincters or penile prostheses.

References:

Macmillan AK, Merrie AE, Marshall RJ, Parry BR. The prevalence of fecal incontinence in community-dwelling adults: a systematic review of the literature. Dis Colon Rectum. 2004 Aug;47(8):1341-9.
Jorge JM, Wexner SD. Etiology and management of fecal incontinence. Dis Colon Rectum. 1993 Jan;36(1):77-97.
Shafik A. Polytetrafluoroethylene injection for the treatment of partial fecal incontinence. Int Surg. 1993 78(2):159-61.
Shafik A. Perianal injection of autologous fat for treatment of sphincteric incontinence. Dis Colon Rectum. 1995 38(6):583-7.
Weiss EG, Efron JE, Nogueras JJ, Wexner SD. Submucosal injection of carbon coated beads is a successful and safe office based treatment for fecal incontinence. Dis Colon Rectum. 2002 45:A46-47, (abstract).
Takahashi T, Garcia-Osogobio S, Valdovinos MA, et al. Radio-frequency energy delivery to the anal canal for the treatment of fecal incontinence. Dis Colon Rectum. 2002 45(7):915-22.
Takahashi T, Garcia-Osogobio S, Valdovinos MA, et al. Extended two-year results of radio-frequency energy delivery for the treatment of fecal incontinence (the Secca procedure). Dis Colon Rectum. 2003 46(6):711-5.
Efron JE, Corman ML, Fleshman J, et al. Safety and effectiveness of temperature-controlled radio-frequency energy delivery to the anal canal (Secca procedure) for the treatment of fecal incontinence. Dis Colon Rectum. 2003 46(12):1606-16.
Wong WD, Congliosi SM, Spencer MP, et al. The safety and efficacy of the artificial bowel sphincter for fecal incontinence: results from a multicenter cohort study. Dis Colon Rectum. 2002 45(9):1139-53.
Mundy L, Merlin TL, Maddern GJ, Hiller JE: Systematic review of safety and effectiveness of an artificial bowel sphincter for faecal incontinence. Br J Surg. 2004 91(6):665-72.
Baeten CG, Bailey HR, Bakka A, et al. Safety and efficacy of dynamic graciloplasty for fecal incontinence: report of a prospective, multicenter trial. Dynamic Graciloplasty Therapy Study Group. Dis Colon Rectum. 2000 43(6):743-51.
Wexner SD, Baeten C, Bailey R, et al. Long-term efficacy of dynamic graciloplasty for fecal incontinence. Dis Colon Rectum. 2002 45(6):809-18.
Matzel KE, Stadelmaier U, Hohenfellner M, Gall FP. Electrical stimulation of sacral spinal nerves for treatment of faecal incontinence. Lancet. 1995 346(8983):1124-7
Jarrett ME, Mowatt G, Glazener CM, et al. Systematic review of sacral nerve stimulation for faecal incontinence and constipation. Br J Surg. 2004 91(12):1559-69