Anorectal physiological testing before and after a successful sphincter repair: a prospective study

Anal sphincter repair for fecal incontinence: experience from a tertiary care centre

AIM

Structural anal sphincter damage may be secondary to obstetric anal sphincter injury, perineal trauma or anorectal surgery. We reviewed the spectrum of anal sphincter injuries and their outcomes in a tertiary care colorectal unit.

METHODS

Data of patients who underwent anal sphincter repair between 2004 and 2008 were analyzed retrospectively. Outcomes were compared with respect to etiology, type of repair, previous attempts at repair and manometry findings. Outcomes were defined as good or poor based on patient satisfaction as the primary criteria.

RESULTS

Thirty-four patients underwent anal sphincter repair. Twenty-two injuries were obstetric, eight traumatic, and four iatrogenic. All patients underwent overlap sphincteroplasty with six additional anterior levatorplasty and seven graciloplasty. Twenty-three (67.6%) patients had a good outcome while nine (26.4%) had a poor outcome. All patients who had augmentation anterior levatorplasty had a good outcome. Fifty percent of patients with a previous sphincter repair and 42.9% requiring augmentation graciloplasty had a poor outcome. Median resting and squeeze anal pressures increased from 57.5 to 70 cmH₂O and 90.25 to 111 cmH₂O in those with a good outcome.

CONCLUSIONS

Overlap sphincteroplasty has a good outcome in majority of the patients with incontinence due to a structural sphincter defect. Additional anterior levatorplasty may improve outcomes. Previous failed repairs or use of a gracilis muscle augmentation may have a worse outcome secondary to poor native sphincter muscle. Improvement in resting and squeeze pressures on anal manometry may be associated with a good outcome.

Injectable silicone biomaterial (PTQ) is more effective than carbon-coated beads (Durasphere) in treating passive faecal incontinence--a randomized trial

OBJECTIVE

Both injectable silicone biomaterial (PTQ) and pyrolytic carbon-coated beads (Durasphere) have been shown to be effective in treating passive faecal incontinence due to internal sphincter dysfunction. This is a randomized study to evaluate their relative safety and efficacy.

METHOD

Forty patients (mean age 59.5 years vs 58.9 years) were randomized to have inter-sphincteric injection of PTQ or submucosal injection of Durasphere. Patients were assessed with anorectal physiology, endoanal ultrasound, a validated incontinence score and quality of life questionnaires.

RESULTS

In the Durasphere group, complications included rectal pain (5%), erosion through rectal mucosa (10%), and type III hypersensitivity reaction (5%). No complications occurred in the PTQ group. Compared with PTQ, Durasphere group has a more rapid action, with improved continence at 2 weeks after injection. In both groups, faecal continence significantly improved 6 weeks after injection, and continued to improve significantly up to 6 months in both groups (P < 0.0001). At 6 weeks, 6 and 12 months after injection, significantly more PTQ patients achieved greater than 50% improvement in Wexner's continence score than Durasphere patients (respectively, P = 0.01; P < 0.0001; P = 0.001). There was a significant improvement in faecal incontinence quality of life scale and the 12-month physical health scale of Short Form-12 health survey in the PTQ group but not in the Durasphere group.

CONCLUSION

In patients with internal sphincter dysfunction, injectable silicone biomaterial was safer and more effective than Durasphere.

Predictive factors for faecal incontinence after third or fourth degree obstetric tears: a clinico-physiologic study

OBJECTIVE

This is a prospective study to review the natural history of anorectal dysfunction after primary repair for third or fourth degree obstetric tear and to identify the predictive factors for significant faecal incontinence.

METHOD

From January 2003 to December 2005, 121 consecutive women (mean age 29.9 +/- 4.7) who sustained third or fourth degree obstetric tears were assessed. All had primary repair by obstetricians. They were assessed using anorectal physiology testing and endoanal ultrasound. Short-term (3-month postpartum) and medium-term (mean 18.8 +/- 7.7 months) Wexner's continence scores were obtained.

RESULTS

Among the 121 women, seven were excluded because of incomplete follow-up. At short-term assessment, 25 out of 114 women were incontinent. One of them underwent another sphincter repair for significant faecal incontinence. Twenty-one and three patients respectively, had mild (Wexner's score 1-4) and moderate (Wexner's score 5-8) symptoms. At medium-term assessment, 24 patients remained incontinent; of these, 20 had mild symptoms (Wexner's score 1-4) and four had moderate incontinence (Wexner's score 5-8). The parity (P = 0.04), degree of obstetric tear (P = 0.036) and short-term Wexner's scores at 3 months postpartum (P < 0.0001) were significantly related to the change in Wexner's scores at medium-term assessment. However, the short-term Wexner's score was the only identifiable predictive factor for significant faecal incontinence.

CONCLUSION

Most women suffering from third or fourth degree obstetric tear were continent or mildly incontinent. Poor Wexner's score at short-term assessment at 3 months postpartum was predictive of faecal incontinence in the medium-term.

Sacral nerve stimulation for fecal incontinence: external anal sphincter defect vs. intact anal sphincter

PURPOSE

This prospective study was designed to assess the effectiveness of sacral nerve stimulation for fecal incontinence in patients with external anal sphincter defect and to evaluate its efficacy regarding presence and size of sphincter defect.

METHODS

Fifty-three consecutive patients who underwent sacral nerve stimulation for fecal incontinence were divided into two groups: external anal sphincter defect group (n = 21) vs. intact sphincter group (n = 32). Follow-up was performed at 3, 6, and 12 months with anorectal physiology, Wexner's score, bowel diary, and quality of life questionnaires.

RESULTS

The external anal sphincter defect group (defect <90 degrees:defect 90 degrees-120 degrees = 11:10) and intact sphincter group were comparable with regard to age (mean, 63 vs. 63.6) and sex. Incidence of internal anal sphincter defect and pudendal neuropathy was similar. All 53 patients benefited from sacral nerve stimulation. Weekly incontinent episodes decreased from 13.8 to 5 (P < 0.0001) for patients with external anal sphincter defects and from 6.7 to 2 (P = 0.001) for patients with intact sphincter at 12-month follow-up. Quality of life scores improved in both groups (P < 0.0125). There was no significant difference in improvement in functional outcomes after sacral nerve stimulation between patients with or without external anal sphincter defects. Clinical benefit of sacral nerve stimulation was similar among patients with external anal sphincter defects, irrespective of its size. Presence of pudendal neuropathy did not affect outcome of neurostimulation.

CONCLUSIONS

Sacral nerve stimulation for fecal incontinence is as effective in patients with external anal sphincter defects as those with intact sphincter and the result is similar for defect size up to 120 degrees of circumference.

Sacral nerve stimulation is more effective than optimal medical therapy for severe fecal incontinence: a randomized, controlled study

PURPOSE

This randomized study was designed to compare the effect of sacral neuromodulation with optimal medical therapy in patients with severe fecal incontinence.

METHODS

Patients (aged 39-86 years) with severe fecal incontinence were randomized to have sacral nerve stimulation (SNS group; n = 60) or best supportive therapy (control; n = 60), which consisted of pelvic floor exercises, bulking agent, and dietary manipulation. Full assessment included endoanal ultrasound, anorectal physiology, two-week bowel diary, and fecal incontinence quality of life index. The follow-up duration was 12 months.

RESULTS

The sacral nerve stimulation group was similar to the control group with regard to gender (F:M = 11:1 vs. 14:1) and age (mean, 63.9 vs. 63 years). The incidence of a defect of < or = 120 degrees of the external anal sphincter and pudendal neuropathy was similar between the groups. Trial screening improved incontinent episodes by more than 50 percent in 54 patients (90 percent). Full-stage sacral nerve stimulation was performed in 53 of these 54 "successful" patients. There were no septic complications. With sacral nerve stimulation, mean incontinent episodes per week decreased from 9.5 to 3.1 (P < 0.0001) and mean incontinent days per week from 3.3 to 1 (P < 0.0001). Perfect continence was accomplished in 25 patients (47.2 percent). In the sacral nerve stimulation group, there was a significant (P < 0.0001) improvement in fecal incontinence quality of life index in all four domains. By contrast, there was no significant improvement in fecal continence and the fecal incontinence quality of life scores in the control group.

CONCLUSIONS

Sacral neuromodulation significantly improved the outcome in patients with severe fecal incontinence compared with the control group undergoing optimal medical therapy.

Evolving therapy for fecal incontinence

BACKGROUND

Fecal incontinence is common and can be socially debilitating. Nonoperative management of fecal incontinence includes dietary modification, antidiarrheal medication, and biofeedback. The traditional surgical approach is sphincteroplasty if there is a defect of the external sphincter. Innovative treatment modalities have included sacral nerve stimulation, injectable implants, dynamic graciloplasty, and artificial bowel sphincter.

DISCUSSION

This review was designed to assess the various surgical options available for fecal incontinence and critically evaluate the evidence behind these procedures. The algorithm in the surgical treatment of fecal incontinence is shifting. Injectable therapy and sacral nerve stimulation are likely to be the mainstay in future treatment of moderate and severe fecal incontinence, respectively. Sphincteroplasty is limited to a small group of patients with isolated defect of the external sphincter. A stoma, although effective, can be avoided in most cases.

Early results of immediate repair of obstetric third-degree tears: 65% are completely asymptomatic despite persistent sphincter defects in 61%

OBJECTIVE

The outcome of immediate repair of obstetric third-degree tears is poorly documented. Immediate repair may give better functional results than delayed repair because scarring is reduced. This aim of this prospective study was to examine the early outcome of immediate repair of third-degree tears.

METHOD

A total of 121 women who had immediate repair of obstetric third-degree tears underwent interview, anal ultrasonography and anorectal physiology.

RESULTS

At review, 79 (65%) were completely asymptomatic (score = 0), 23 (19%), had minor flatus incontinence or mild urgency causing no compromise to their quality of life (score 1-4), and 19 (16%) had clinically embarrassing faecal incontinence (score 5-24). Thirty-nine (32%) had an intact internal anal sphincter (IAS) and external anal sphincter (EAS) (i.e. a successful repair), eight (7%) had a defect in the IAS alone but the EAS was intact (i.e. a successful repair but a residual IAS defect), 43 (35%) had a residual defect in the EAS alone (IAS intact) and 31 (26%) had a persistent defect in the IAS and EAS. Residual defects in either or both of the sphincters were associated with a significantly higher incidence of abnormal resting and squeeze anal pressures. Anal manometry had no correlation with symptoms. The highest proportion of severe incontinence was in those with an IAS defect alone (37%) and when there was a residual IAS and EAS defect (24%). Only 2 of 39 (5%) with an intact IAS and EAS had severe incontinence and only 8 of 43 (18%) with a residual EAS defect alone had severe faecal incontinence.

CONCLUSION

These results indicate a good outcome following immediate repair of third-degree obstetric tears and emphasize the role of the IAS in providing continence.

Preoperative chemoradiation for rectal cancer causes prolonged pudendal nerve terminal motor latency

PURPOSE

A worsened anorectal function after chemoradiation for high-risk rectal cancer is often attributed to radiation damage of the anorectum and pelvic floor. Its impact on pudendal nerve function is unclear. This prospective study evaluated the short-term effect of preoperative combined chemoradiation on anorectal physiologic and pudendal nerve function.

METHODS

Sixty-six patients (39 men, 27 women) with localized resectable (T3, T4, or N1) rectal cancer were included in the study. All patients received 45 Gy (1.8 Gy/day in 25 fractions) over five weeks, plus 5-fluorouracil (350 mg/m2/day) and leucovorin (20 mg/m2/day) concurrently on days 1 to 5 and 29 to 33. Patients who had rectal cancer with a distal margin within 6 cm of the anal verge had the anus included in the field of radiotherapy (Group A, n = 26). Patients who had rectal cancer with a distal margin 6 to 12 cm from the anal verge had shielding of the anus during radiotherapy (Group B, n = 40). The Wexner continence score, anorectal manometry and pudendal nerve terminal motor latency were assessed at baseline and four weeks after completion of chemoradiation.

RESULTS

The median Wexner score deteriorated significantly (P < 0.0001) from 0 to 2.5 for both Groups A (range, 0-8) and B (range, 0-14). The maximum resting anal pressures were unchanged after chemoradiation. The maximum squeeze anal pressures were reduced (mean = 166.5-157.5 mmHg) after chemoradiation. This change was similar in both Groups A and B. Eighteen patients (Group A = 7, Group B = 11) developed prolonged pudendal nerve terminal motor latency after chemoradiation. These 18 patients similarly had a worsened median Wexner continence score (range, 0-3) and maximum squeeze anal pressures (mean = 165.5-144 mmHg). The results obtained were independent of tumor response to chemoradiation.

CONCLUSIONS

Preoperative chemoradiation for rectal cancer carries a significant risk of pudendal neuropathy, which might contribute to the incidence of fecal incontinence after restorative proctectomy for rectal cancer.

Injectable silicone biomaterial for fecal incontinence caused by internal anal sphincter dysfunction is effective

PURPOSE

Fecal incontinence caused by a weak or disrupted internal anal sphincter is common but there has been no effective treatment. This prospective study evaluates the medium-term clinical effects of an injectable silicone biomaterial, PTP (Bioplastique), used to augment the internal anal sphincter.

METHOD

Eighty-two patients (64 females; median age, 66 years) with severe fecal incontinence and a low anal resting pressure caused by internal anal sphincter dysfunction (defect, n = 11; intact, n = 71) were randomized to PTP injection into intersphincteric space and internal anal sphincter with (Group A, n = 42) or without (Group B, n = 40) guidance by endoanal ultrasound. Both groups were similar in terms of age, gender, past anorectal surgery, duration of follow-up (median, 6 months; range, 1-12 months), and baseline continence score. Sixty-two percent of Group A and 55 percent of Group B had prolonged pudendal nerve terminal motor latency.

RESULTS

There was no significant complication. Two patients in Group A and four patients in Group B noted minor discomfort at injection sites. At one month postprocedure, endoanal ultrasound confirmed retention of silicone biomaterial without migration. In both groups, fecal continence was significantly improved by PTP implants 1 month after injection, but continued to improve significantly for up to 12 months in Group A and 6 months in Group B (P < 0.001). Improvement in fecal continence and maximum anal resting pressure was significantly greater in Group A, in whom injection was guided by endoanal ultrasound, than in Group B. At three months after injection, significantly more Group A patients than Group B patients achieved >50 percent improvement in Wexner's continence score (69 percent vs. 40 percent; P = 0.014). Ninety-three percent of Group A and 92 percent of Group B had >50 percent improvement in global quality of life scores (visual analog scale). At a median follow-up of 6 months, all domains of the fecal incontinence quality of life scale improved significantly in both groups; however, the physical function and mental health scores of Short Form-12 only improved in Group A. A prolonged pudendal nerve terminal motor latency had no effect on functional outcome in either group.

CONCLUSION

Injection of silicone biomaterial provided a marked improvement in fecal continence and quality of life in patients with internal sphincter dysfunction, despite the presence of pudendal neuropathy.