Introduction The aim of this study was to compare standard 8 channel water perfused catheter to a HARM 28 channel catheter in patients with both evacuatory bowel disorders and faecal incontinence.

Methods 50 patients referred for WPM testing also underwent simultaneous HRAM testing.

WPM was performed using an 8 channel radial arranged catheter using an automated puller to evaluate vector volume pressure profiles of the anal sphincter complex, and also a station pull through technique to further assess pressure profile.

Rectal sensory function was evaluated using a separate water perfused catheter.

This was compared to a HRAM 28 pressure catheter with 28 circumferential sensors along 6 cm length. A balloon was attached over a rectal sensor which would allow evaluation of rectal pressure change throughout the entire study.

Anal canal resting pressure, squeeze pressure, anal canal length, rectal sensations and presence recto-anal inhibitory reflex were recorded using both catheters.

Comparison of the anal canal pressures using the water perfused catheter were made to the pressure profile from the HRAM studies.

The HRAM also allows for real time pressure measurement of anal canal pressure as a balloon is inflates in the rectum, simulating rectal filling. This in theory give a more physiology sphincter contraction. This was compared to patient symptoms.

Results 50 patients with either faecal incontinence symptoms and or evcuatory disorders underwent both water perfused manometry and High resolution ano rectal manometry.

(24 with evcuatory difficulties/ constipation, 21 with faecal incontinence.

The results are summarised in the table below.

Analysing the squeezes pressure during balloon distension showed that there was a significant difference between those patients with faecal incontinence (40 mmHg) and constipation (77 mmHg) (p = 0.036).

Conclusion There is good correlation between the modalities and the HRAM can obtain substantially greater real time physiological information. HRAM with balloon rectal distension appears to be more sensitive in identifying difference between patients with no faecal incontinence and faecal incontinence though further work is required following this preliminary study.

Disclosure of Interest None Declared