Short-term clinical and manometric outcomes of percutaneous tibial nerve stimulation for faecal incontinence: a large single-centre series

BACKGROUND

Faecal incontinence (FI) is common, with a significant impact on quality of life. Percutaneous tibial nerve stimulation (PTNS) is a therapy for FI; however, its role has recently been questioned. Here we report the short-term clinical and manometric outcomes in a large tertiary centre.

METHODS

A retrospective review of a prospective PTNS database was performed, extracting patient-reported FI outcome measures including bowel diary, the St Marks's Incontinence Score (SMIS) and Manchester Health Questionnaire (MHQ). Successful treatment was > 50% improvement in symptoms, whilst a partial response was 25-50% improvement. High-resolution anorectal manometry (HRAM) results before and after PTNS were recorded.

RESULTS

Data were available from 135 patients [119 (88%) females; median age: 60 years (range: 27-82years)]. Overall, patients reported a reduction in urge FI (2.5-1) and passive FI episodes (2-1.5; p < 0.05) alongside a reduction in SMIS (16.5-14) and MHQ (517.5-460.0; p < 0.001). Some 76 (56%) patients reported success, whilst a further 20 (15%) reported a partial response. There were statistically significant reductions in rectal balloon thresholds and an increase in incremental squeeze pressure; however, these changes were independent of treatment success.

CONCLUSION

Patients report PTNS improves FI symptoms in the short term. Despite this improvement, changes in HRAM parameters were independent of this success. HRAM may be unable to measure the clinical effect of PTNS, or there remains the possibility of a placebo effect. Further work is required to define the role of PTNS in the treatment of FI.

Intra-subject Variability in High Resolution Anorectal Manometry Using the London Classification: Diagnostic and Therapeutic Implications

This retrospective pilot study conducted on a community-based cohort of both men and women of various ages and underlying clinical presentations examined the durability and reproducibility of HR-ARM findings influencing their potential impact on clinical decision-making at the point of care (Jameson et al. in Br J Surg 81:1689-1692, 1994). The key finding of our study was that only a minority of patients who underwent repeat anorectal manometry as analyzed by the London Classification had stable manometric findings, raising questions regarding the validity of a single manometric measurement, as currently analyzed, for clinical decision-making.

Clinical benefit of high resolution anorectal manometry for the evaluation of anal function after intersphincteric resection

AIM

Intersphincteric resection (ISR) is an advanced anus-preserving operation for treating low rectal cancer while avoiding colostomy. High-resolution anorectal manometry (HR-ARM) allows objective and accurate evaluation of anal function. However, correlations between anal function after ISR and HR-ARM parameters are unknown. The aim of the study was to evaluate HR-ARM for objective evaluation of anal function after ISR.

METHOD

A total of 81 patients who underwent ISR at our hospital between October 2014 and March 2016 were identified from our prospectively collected database and electronic medical records. Of these, 68 patients who had been evaluated using HR-ARM both before and after ISR were included in the study. Faecal incontinence (FI) was assessed by Wexner score. Multivariate analysis was performed to determine risk factors for severe FI after ISR.

RESULTS

Maximum resting pressure (MRP) (P < 0.001) and maximum squeeze pressure (P = 0.04) were significantly lower after ISR, and MRP (P < 0.001) and maximum squeeze pressure (P = 0.02) were significantly lower after total (or subtotal) ISR than after partial ISR. The overall incidence of severe FI after ISR was 18% (12/68), and a high pressure zone before ISR ≤ 3 cm (P = 0.007) and MRP before ISR > 60 mmHg (P = 0.02) were independently associated with an elevated incidence of severe FI after ISR. Decreased preoperative MRP also correlated with severe FI after ISR (P = 0.008).

CONCLUSION

HR-ARM is reliable for the evaluation of anal function after ISR, and the high pressure zone and MRP may be useful preoperative predictors of severe FI after ISR.

[Normal values for solid state high resolution anorectal manometry in healthy adult volunteers]

Objective: To explore the normal values for two-dimension solid state high resolution anorectal manometry (HRAM) in healthy adult volunteers. Methods: The healthy adult volunteers were recruited by advertisement and underwent solid state HRAM in the left lateral position. Anorectal pressures and rectal sensation were recorded and analyzed. Results: (1) A total of 126 Chinese healthy adult volunteers (male: 50 cases (39.7%); age: (37.5±14.2) years old ) were recruited in this study. (2) Mean anal resting pressure (MERP) was (71.8±17.3) mmHg (1 mmHg=0.133 kPa). Maximum anal resting pressure (MARP) was (79.3±17.8) mmHg, Maximum anal squeeze pressure (MSP) was (178.7±52.8) mmHg. Anal high pressure zone (HPZ) length was (3.4±0.6) cm. During simulated evacuation, residual anal pressure (RAP) was (63.8±20.5) mmHg, and anal relaxation rate (ARR) was (37.0±11.5)%. Rectal threshold volume for first sensation (FST), desire to defecate (DDT), urgency to defecate (UDT) and maximum discomfort (MDT) was (47.4±10.0) ml, (84.5±18.2) ml, (125.8±28.5) ml, and (175.5±36.1) ml, respectively. (3) Compared with female subjects, male subjects had higher MSP[(211.0±50.7) mmHg vs (157.5±42.5) mmHg], RAP[(71.6±18.1) mmHg vs (58.8±20.5) mmHg]and rectal MDT[(187.0±36.4) mmHg vs (168.0±34.1)mmHg], but lower ARR[(32.1±8.0)% vs (40.2±12.3)%], all P<0.01. (4) MERP, MARP, MSP and rectal MDT were higher in young group (≤40 years old), all P<0.05. Conclusions: These observations provide normal values for two-dimension solid state HRAM, which have significant difference between genders and different age groups.

Water-perfused manometry vs three-dimensional high-resolution manometry: a comparative study on a large patient population with anorectal disorders

AIM

Our aim was to compare for the first time measurements obtained with water-perfused catheter anorectal manometry and three-dimensional (3D) high-resolution manometry in patients with anorectal disorders.

METHOD

Consecutive patients referred to our centre for anorectal manometry (ARM) were recruited to undergo the two procedures successively. Conventional manometry was carried out using a water-perfused catheter (WPAM) and high-resolution manometry was achieved with a 3D probe (3DHRAM). For each procedure, parameters recorded included the following: anal canal length, resting pressure, squeeze pressure and rectal sensitivity.

RESULTS

Two hundred and one patients were included in this study. The mean values for resting and squeeze pressures were correlated and found to be significantly higher when measured with 3DHRAM than with WPAM. However, the length of the anal canal was not significantly different when measured by the two techniques without correlation between the two mean values obtained. The presence of the rectoanal inhibitory reflex was systematically assessed by both WPAM and 3DHRAM and anismus was also systematically diagnosed by both WPAM and 3DHRAM.

CONCLUSION

The pressure values obtained with 3DHRAM are correlated with those measured with conventional manometry but are systematically higher. 3DHRAM has the advantage of providing a pressure recording over the entire length and circumference of the anal canal, allowing a more useful physiological assessment of anorectal function.