Unilateral pudendal neuropathy is common in patients with fecal incontinence

Systematic review and meta-analysis of anal motor and rectal sensory dysfunction in male and female patients undergoing anorectal manometry for symptoms of faecal incontinence

AIM

Manometry is the best established technique to assess anorectal function in faecal incontinence. By systematic review, pooled prevalences of anal hypotonia/hypocontractility and rectal hypersensitivity/hyposensitivity in male and female patients were determined in controlled studies using anorectal manometry.

METHODS

Searches of MEDLINE and Embase were completed. Screening, data extraction and bias assessment were performed by two reviewers. Meta-analysis was performed based on a random effects model with heterogeneity evaluated by I² .

RESULTS

Of 2116 identified records, only 13 studies (2981 faecal incontinence patients; 1028 controls) met the inclusion criteria. Anal tone was evaluated in 10 studies and contractility in 11; rectal sensitivity in five. Only three studies had low risk of bias. Pooled prevalence of anal hypotonia was 44% (95% CI 32-56, I² = 96.35%) in women and 27% (95% CI 14-40, I² = 94.12%) in men. The pooled prevalence of anal hypocontractility was 69% (95% CI 57-81; I² = 98.17%) in women and 36% (95% CI 18-53; I² = 96.77%) in men. Pooled prevalence of rectal hypersensitivity was 10% (95% CI 4-15; I² = 80.09%) in women and 4% (95% CI 1-7; I² = 51.25%) in men, whereas hyposensitivity had a pooled prevalence of 7% (95% CI 5-9; I² = 0.00%) in women compared to 19% (95% CI 15-23; I² = 0.00%) in men.

CONCLUSIONS

The number of appropriately controlled studies of anorectal manometry is small with fewer still at low risk of bias. Results were subject to gender differences, wide confidence intervals and high heterogeneity indicating the need for international collective effort to harmonize practice and reporting to improve certainty of diagnosis.

Systematic evaluation of cough-anorectal pressure responses in health and in fecal incontinence: A high-resolution anorectal manometry study

BACKGROUND

Anorectal manometry is the most commonly performed test of anorectal function. The cough-anorectal response is frequently assessed as part of a routine manometric investigation but has not previously been the subject of detailed analysis. This study systematically examined anorectal pressure responses to cough in health and evaluated the impact of parity and symptoms of fecal incontinence (FI) on measurements.

METHODS

High-resolution anorectal manometry (HR-ARM) traces from nulliparous (n = 25) and parous (n = 25) healthy volunteers (HV: aged 41, range 18-64), and 57 parous patients with FI (age 47, range 28-72) were retrospectively reviewed. Cough-anorectal pressure responses were analyzed between groups by qualitative and quantitative approaches.

KEY RESULTS

In health, traditional anal pressure measurements ("rest" and "squeeze") were similar between nulliparous and parous women. In contrast, incremental anal-rectal pressure difference during cough significantly differed: nulliparous 42 mm Hg (95% CI: 21-64) vs. parous 6 mm Hg (-14-25), P < 0.036). This measure also differed significantly between nulliparous HVs and patients with FI (-2 mm Hg (95% CI: -15-12), P < 0.001), but not between parous HVs and FI. Qualitatively, a color-contour trace resembling a "spear" in the upper anal canal was observed uniquely in FI. Of 25 patients with normal anal function by traditional measures, cough parameters were abnormal in 52%.

CONCLUSIONS AND INFERENCES

Novel HR-ARM measures during coughing revealed differences in anal function between nulliparous and parous HV, and patients with FI, which were not detected by traditional measures. Cough-anorectal measurements may improve manometric yield, though clinical utility would require assessment by longitudinal studies.

What Is Fecal Incontinence That Urologists Need to Know?

Fecal incontinence (FI) undoubtedly reduces quality of life and adversely affects the social life of the affected individual. FI has a higher prevalence with age and has an equivalent prevalence to urinary incontinence in patients with genitourinary disease, but is often not confirmed in these cases. A thorough investigation is needed to diagnose FI, with the common etiology of this condition in mind, and several questionnaires can be used to identify symptoms. The physical examination contains digital rectal examination carries out to identify the patient's condition. Ultrasound, colonoscopy, and rectum pressure test can be performed. Patients educated in diet-related issues, bowel movements, and defecation mechanism. Nonoperative options such as diet control and Kegel exercise should be performed at first. Surgical treatment of FI is considered when conservative management and oral medications produce no improvement. Surgical options include less invasive procedures like bulking agent injections, and more involved approaches from sacral nerve stimulation to invasive direct sphincter repair and artificial bowel sphincter insertion. Good outcomes in FI cases have also recently been reported for barrier devices.

Cortico-anorectal, Spino-anorectal, and Cortico-spinal Nerve Conduction and Locus of Neuronal Injury in Patients With Fecal Incontinence

BACKGROUND & AIMS

The neuropathophysiology of fecal incontinence (FI) is incompletely understood. We examined the efferent brain-anorectal and spino-anorectal motor-evoked potentials (MEP) to characterize the locus of neuronal injury in patients with FI.

METHODS

We performed bilateral transcranial, translumbar, and transsacral magnetic stimulations in 27 patients with FI (19 female) and 31 healthy individuals (controls, 20 female) from 2015 through 2017. MEPs were recorded simultaneously from the rectum and anus using 4 ring electrodes. The difference in MEP latencies between the transcranial (TMS) and translumbar transsacral magnetic stimulations was calculated as cortico-spinal conduction time. MEP data were compared between patients with FI and controls. Patients filled out questionnaires that assessed the severity and effects of FI.

RESULTS

The MEP latencies with TMS were significantly longer in patients with FI than controls at most sites, and on both sides (P < .05). Almost all translumbar and transsacral MEP latencies were significantly prolonged in patients with FI vs controls (P < .01). The cortico-spinal conduction time were similar, on both sides, between patients with FI and controls. Ninety-three percent of patients had 1 or more abnormal translumbar and transsacral latencies, but neuropathy was patchy and variable, and not associated with sex or anal sphincter function or defects.

CONCLUSIONS

Patients with FI have significant neuropathy that affects the cortico-anorectal and spino-anorectal efferent pathways. The primary loci are the lumbo-rectal, lumbo-anal, sacro-rectal, and sacro-anal nerves; the cortico-spinal segment appears intact. Peripheral spino-anal and spino-rectal neuropathy might therefore contribute to the pathogenesis of FI.

Fecal incontinence - Challenges and solutions

Fecal incontinence is not a diagnosis but a frequent and debilitating common final pathway symptom resulting from numerous different causes. Incontinence not only impacts the patient's self-esteem and quality of life but may result in significant secondary morbidity, disability, and cost. Treatment is difficult without any panacea and an individualized approach should be chosen that frequently combines different modalities. Several new technologies have been developed and their specific roles will have to be defined. The scope of this review is outline the evaluation and treatment of patients with fecal incontinence.

Does preoperative anal physiology testing or ultrasonography predict clinical outcome with sacral neuromodulation for fecal incontinence?

INTRODUCTION AND HYPOTHESIS

To determine the value of preoperative anal physiology testing and transanal ultrasonography in predicting clinical response to sacral neuromodulation for fecal incontinence.

METHODS

We report a retrospective study of all patients treated with sacral neuromodulation for fecal incontinence in a single practice between 2011 and 2014 was performed. Patient demographics included age, gender, comorbidities, presence of an ultrasound-defined external sphincter defect, and history of prior anal sphincter repair. Cleveland Clinic Florida (CCF) scores were used to assess the severity of fecal incontinence at baseline, and at 3, 6 and 12 months. Pearson's correlation coefficient was used to evaluate the relationship between preoperative physiology testing and ultrasonography and patient outcome.

RESULTS

Sacral neuromodulation was trialed in 60 patients, of whom 31 had anorectal physiology testing and 29 did not. Patients who were tested were younger (60.9 vs. 71.4 years, p = 0.013) and more likely to have had a prior overlapping sphincteroplasty (40.5% vs. 15%, p = 0.043). Among patients who progressed to complete system implantation, CCF scores at 3 and 12 months were similar whether they had physiology testing or not. Likewise, patient outcome did not correlate with the finding of an ultrasound-defined external sphincter defect. Pearson's correlation coefficient was used to evaluate the relationship between the test results and the 3-month CCF scores. CCF scores 3 months after full system implantation did not correlate with the presence or size of an external sphincter defect, resting or squeeze pressure, pudendal nerve terminal motor latency, rectoanal inhibitory reflex, or minimum detectable volume.

CONCLUSIONS

Anal physiology testing and ultrasonography were not predictive of clinical outcomes among patients treated with sacral neuromodulation for fecal incontinence.

Prolonged pudendal nerve terminal motor latency is associated with decreased resting and squeeze pressures in the intact anal sphincter

AIM

To determine the contribution of the pudendal nerve to the anal continence mechanism by determining the correlation between pudendal nerve terminal motor latency (PNTML) and resting and squeeze anal canal pressures.

METHOD

In all, 1051 patients were investigated with anorectal physiology studies between January 1998 and July 2010. Of these, 213 patients had intact anal sphincters on endoanal ultrasound and had undergone PNTML testing and anal manometry with measurement of resting and squeeze pressures. The relationship between PNTML and mean resting and squeeze pressures was compared in these patients with an intact anal sphincter. Values were compared using a two-sample t test with equal variances. A P value of < 0.05 was considered significant.

RESULTS

Of these patients 40.8% had normal PNTML bilaterally, 9.9% had slow PNTML bilaterally and 21.6% had a unilateral slow PNTML. Mean resting pressure was significantly reduced in patients with unilateral slow and bilateral slow PNTML compared with normal. The magnitude of the reduction was 28% and 19% respectively. Mean squeeze pressure was significantly reduced in patients with unilateral slow and bilateral slow PNTML compared with normal. The magnitude of the reduction was 18% and 23% respectively.

CONCLUSION

In patients with an intact anal sphincter, either unilaterally or bilaterally prolonged PNTMLs are associated with significantly decreased resting and squeeze pressures. Our results suggest that both internal and external sphincter function is impaired with pudendal nerve injury. The inhibition of internal sphincter function may be due to damage of autonomic, principally sympathetic fibres carried in the pudendal nerve.

Fecal incontinence in men: coexistent constipation and impact of rectal hyposensitivity

BACKGROUND

The pathophysiology of fecal incontinence in men is poorly established.

OBJECTIVE

The aim of this study was to assess the coexistence of constipation and determine the impact of rectal sensorimotor dysfunction in males with fecal incontinence.

SETTING

This study was conducted at a tertiary referral center.

PATIENTS

Included were adult male patients referred for the investigation of fecal incontinence over a 5-year period who underwent full anorectal physiology testing and completed a standardized symptom questionnaire.

INTERVENTION

Standardized symptom questionnaires were fully completed, and anorectal physiologic test results (including evacuation proctography) were evaluated.

MAIN OUTCOME MEASURES

: The primary outcomes measured were the frequency of symptoms of associated constipation, the association of blunted rectal sensation (rectal hyposensitivity) with symptoms, and other physiologic measures.

RESULTS

One hundred sixty patients met the inclusion criteria, and 47% of these patients described concurrent constipation. Fifty-four patients (34%) had sphincter dysfunction on manometry, only 19 of whom had structural abnormalities on ultrasound. Overall, 28 patients (18%) had rectal sensory dysfunction, 26 (93%) of whom had rectal hyposensitivity. Patients with rectal hyposensitivity were more likely to subjectively report constipation (77%) in comparison with patients with normal rectal sensation (44%; p = 0.001), allied with decreased bowel frequency (19% vs 2%; p = 0.003) and a sense of difficulty evacuating stool (27% vs 8%; p = 0.008). Cleveland Clinic constipation scores were higher in patients with rectal hyposensitivity (median score, 13 (interquartile range: 8-17) vs normosensate, 9 (5-13); p = 0.004). On proctography, a higher proportion of patients with rectal hyposensitivity had protracted defecation (>180 s; 35% vs 10%; p = 0.024) and incomplete rectal evacuation (<55% of barium neostool expelled, 50% vs 20%; p = 0.02).

LIMITATIONS

: This study was limited by the retrospective analysis of prospectively collected data.

CONCLUSIONS

Only one-third of incontinent men had sphincteric dysfunction. Other pathophysiologies must therefore be considered. Nearly half of patients reported concurrent constipation, and one-sixth had rectal hyposensitivity, which was associated with higher frequencies of both symptomatic and objective measures of rectal evacuatory dysfunction. In the majority of adult males, fecal incontinence may represent a secondary phenomenon.

Manometric, sensorimotor, and neurophysiologic evaluation of anorectal function

With advances in diagnostic technology, it is now accepted that in the field of functional bowel disorders, symptom-based assessment is unsatisfactory as the sole means of directing therapy. A robust taxonomy based on underlying pathophysiology has been suggested, highlighting a crucial role for physiologic testing in clinical practice. A wide number of complementary investigations currently exist for the assessment of anorectal structure and function, some of which have a clinical impact in patients with functional disorders of evacuation and continence by markedly improving diagnostic yield and altering management. The techniques, limitations, measurements, and clinical use of manometric, sensorimotor, and neurophysiologic tests of anorectal function are presented.