Aim To study the response of the rectum to the voluntary squeeze of anal sphincters in normal controls in comparison with patients with faecal incontinence.
Method Lower rectal diameter and intrarectal pressures are recorded during rest and squeeze by lateral view evacuation proctography (defecography) and anorectal manometry in 35 normal controls and in 35 patients with faecal incontinence.
Results 26 and 27 out of 35 patients in each group were males, with average age of 39 years old. There is highly significant difference in resting rectal pressure (RRP) and squeeze rectal pressure (SRP) and resting rectal diameter (RRD) and squeeze rectal diameter (SRD) in normal controls (p < 0.01). There is also significant correlation between the change in rectal diameter and rectal pressure (p = 0.02). No significant different in RRD and SRD in group of patients complaining of faecal incontinence (p = 0.095), with no correlation between the change in rectal pressure and diameter (0.0727). There is no significant difference in RRP (p = 0.169). There is highly significant difference in SRP (p < 0.01), change in rectal pressure (p < 0.01) and change in rectal diameter (p < 0.01). There was delay in the rectal pressure of average of 1.1 sec (0.5–1.4) between the squeeze and rectal pressure, suggestive of retrograde anorectal wave.
Conclusion The rectal contraction during squeeze (rather than inhibitory, as suggested before) may allow retrograde evacuation of the rectum and delayed defecation in normal controls. This act is weak in incontinence group which may contribute to pathophysiology in those patients.
Disclosure of interest None Declared.