Anal Weakness Research Articles

High-resolution anorectal manometry: An expensive hobby or worth every penny?

Introduced approximately 10years ago, high-resolution manometry catheters have fostered interest in anorectal manometry. This review, which accompanies two articles in this issue of Neurogastroenterology and Motility, reviews the methods, clinical indications, utility, and pitfalls of anorectal manometry and revisits the American Gastroenterological Association (AGA) Medical Position Statement on Anorectal Testing Techniques, which was last published in 1999. High-resolution manometry provides a refined assessment of the anorectal pressure profile, obviates the need for station pull-through maneuvers, and minimizes movement artifacts. In selected cases, this refined assessment may be useful for identifying structural abnormalities or anal weakness. However, many manometry patterns that were previously regarded as abnormal are also observed in a majority of healthy patients, which substantially limits the utility of manometry for identifying defecatory disorders. It is our impression that most conclusions of the AGA medical position statement from 1999 remain valid today. High-resolution techniques have not substantially affected the number of publications on or management of anorectal disorders. The ongoing efforts of an international working group to standardize techniques for anorectal manometry are welcome. Although high-resolution manometry is more than an expensive hobby, improvements in catheter design and further research to rigorously define and evaluate these techniques are necessary to determine if they are worth every penny.

Prospective cohort study of phenotypic variation based on an anal sphincter function in adults with fecal incontinence.

One-third of patients with fecal incontinence (FI) do not have any anal dysfunction. The aim was to characterize patients with FI with normal anal function compared with patients with anal weakness. The general characteristics and data of anal manometry, endosonography, and defecography of patients who were evaluated for FI at a single institution from 2005 to 2015 were prospectively assessed. Fecal incontinence was defined by the Cleveland Clinic Incontinence Score (CCIS) >4. Anal weakness was defined by one or more of the three following parameters: <25 mmHg at the upper part of the anal canal, <26 mmHg at the lower part of the anal canal, and <60 mmHg for the mean squeeze pressure. A total of 439 patients with FI were included (152 with normal anal function/287 with anal weakness). Severe constipation (Kess score ≥21) was predominant in patients with normal anal function (44/151 vs 50/284, respectively; p = 0.0054). Fecal incontinence with normal anal function was significantly associated with lower age (>63 years; odds ratio [OR] = 0.29), higher weight (>65 kg; OR = 1.69), fecal urgency (OR = 1.58), less severe FI score (CCIS score >10; OR = 0.52), higher abdominal pressure (>36 mmHg; OR = 2.15), and paradoxical puborectal contraction (OR = 2.07) in a multivariate analysis model. Fecal incontinence with normal anal function is a specific phenotype that involves distal constipation and may be an early stage of FI with anal weakness. Physicians should adapt their management to focus on the treatment of constipation.

A novel technique for bedside anorectal manometry in humans.

Currently, anorectal manometry (ARM), which is used to diagnose defecatory disorders and identify anal weakness in fecal incontinence (FI) is generally conducted in specialized laboratories. Our aims were to compare anorectal functions measured with high-resolution manometry (HRM) and a novel portable manometry device. Anal pressures at rest, during squeeze, and simulated evacuation, and rectal sensation were evaluated with portable and HRM in 20 healthy women, 19 women with constipation, and 11 with FI. The relationship between anal pressures measured with portable and HRM was assessed by the concordance correlation coefficient (CCC), Bland Altman test, and paired t-tests. Anal pressures at rest (CCC 0.45; 95% CI: 0.29, 0.58) and during squeeze (CCC 0.60; 95% CI: 0.46, 0.72) measured with portable and HRM were correlated and inversely associated with the risk of FI. During simulated evacuation, the CCC for rectal pressure (0.62; 95% CI: 0.43, 0.76) was greater than that for anal pressure (CCC 0.22; 95% CI: 0.04, 0.39) and the rectoanal gradient (CCC 0.22; 95% CI: 0.02, 0.41). Rectal sensory thresholds for first sensation, the desire to defecate, and urgency measured by portable and HRM were also significantly correlated between techniques. For several parameters, differences between portable and HRM were statistically significant and the Bland Altman test was positive. Anorectal pressures and rectal sensation can be conveniently measured by portable manometry and are significantly correlated with high-resolution manometry.

Sa1370 Utility of MRI Defecography After Manometry in the Diagnosis and Management of Constipation and Fecal Incontinence

G A A b st ra ct s from 40.25 (SD 21.6) to 73.25 (SD 41.5) mmHg p=0.031, correspondingly (Graph 1 & Figure 1). Due to the physiologic improvement observed at the second ARM, in 4 (33%) cases the recommendation of the pelvic floor clinic was changed and vaginal delivery was considered as an acceptable option in subsequent deliveries. Conclusions: When there is discrepancy between severity of anal weakness on ARM and anatomy based on EAUS findings at three months postpartum, a second ARM within 6 months after pelvic floor physiotherapy may show significant improvement in external anal sphincter function. This repeated evaluation may alter the decision regarding future delivery mode, in up to one third of the patients.

Effect of nifedipine on anorectal sensorimotor functions in health and fecal incontinence

The mechanisms of increased rectal stiffness in women with fecal incontinence (FI) and rectal urgency are not understood. Our hypothesis was that distention-induced activation of mechanosensitive L-type calcium channels in smooth muscle contributes to increased rectal stiffness in FI. Anal pressures, rectal distensibility (compliance, capacity, and contractile response to sinusoidal oscillation), and rectal sensation were assessed before and after oral nifedipine (30 + 10 mg) or placebo in 16 women with FI and 16 asymptomatic women. At baseline, FI patients had a lower anal pressure increment during squeeze (health, 66.9 ± 7.6: FI, 28.6 ± 5.9, mean ± SE, P ≤ 0.01), lower rectal capacity (P = 0.052), and higher rectal pressures during sinusoidal oscillation (health, 13.7 ± 3.2: FI, 21.7 ± 1.4, mean ± SE, P = 0.02) than the healthy women, which suggests an exaggerated rectal contractile response to distention. Nifedipine decreased mean BP, increased heart rate (P = 0.01 vs. placebo), and reduced anal resting pressure (P ≤ 0.01) but did not significantly modify rectal distensibility in health or FI. Plasma nifedipine concentrations (health, 103 ± 21 ng/ml: FI, 162 ± 34 ng/ml) were correlated with increased rectal compliance (r = 0.6, P = 0.02) in all study participants and, in healthy subjects, with decreased rectal pressures during sinusoidal oscillation (r = 0.86, P = 0.01), indicative of reduced stiffness. No consistent effects on rectal perception were observed. These observations confirm that FI is associated with anal weakness and increased rectal stiffness. At therapeutic plasma concentrations, nifedipine reduced anal resting pressure but did not improve rectal distensibility in FI, outcomes that argue against a predominant contribution of myogenic L-type calcium channels to reduced rectal distensibility in FI.

Overt Rectal Prolapse and Fecal Incontinence

Rectal prolapse is frequently associated with fecal incontinence; however, the relationship is questionable. The study was designed to evaluate fecal incontinence in a large consecutive series of patients who suffered from rectal prolapse, focusing on both past history, anal physiology, and imaging. Eighty-eight consecutive patients who suffered from an overt rectal prolapse (72 women, 16 men; mean age, 51.1 +/- 19.5 years) as a main symptom were analyzed; 48 patients also experienced fecal incontinence compared with 40 without incontinence. Logistic regression analyses were performed. The two groups of patients did not differ with respect to parity, weekly stool frequency, main duration of symptoms before referral, occurrence of dyschezia, and digital help to defecate. Patients with prolapse who were older than 45 years (odds ratio (OR), 4.51 (1.49-13.62); P = 0.007) and those with a past history of hemorrhoidectomy (OR, 9.05 (1.68-48.8); P = 0.01) were significantly more incontinent. Incontinent group showed frequent internal anal sphincter defect compared with the continent group (60 vs. 6.2 percent; P = 0.0018). In patients with overt rectal prolapse, the occurrence of fecal incontinence needs special consideration for age and previous hemorrhoid surgery as causative factors. Anal weakness and sphincter defects are frequently observed.

Fecal incontinence with normal anal canal pressures: where is the pitfall?

OBJECTIVE: One third of subjects who suffer from fecal incontinence are found to have values within the normal range when anal manometry is performed. For these patients, one hypothesis is that impaired rectal adaptation to distension may occur. The aim of our study was to analyze anorectal responses to rectal isobaric distension in this population. METHODS: This was a prospective study conducted in 51 consecutive incontinent patients (45 female, six male) divided into two groups according to their functional anal state: absence (19 patients aged 55 ± 6 yr) or presence of manometric anal weakness (32 patients aged 59 ± 2 yr). The subjects were submitted to two randomized modes of rectal isobaric distension (tonic, phasic) with an electronic barostat. Anal pressures, perception, and volumes of the rectum were recorded at six different preselected pressures. RESULTS: As compared with those having anal weakness, patients with no anal weakness retained higher mean pressures at both upper (36.9 ± 2.2 vs 22.9 ± 1.4 mm Hg; p = 0.01) and lower parts (41.0 ± 2.0 vs 23.3 ± 1.4 mm Hg; p = 0.002) of the anal canal, similar perception scores, but much lower rectal volumes (68.5 ± 5.5 vs 121.8 ± 7.0 ml; p = 0.008) in response to rectal isobaric distension. CONCLUSION: A decrease in rectal adaptation could be involved in fecal leakage in patients with no anal manometric weakness.