RECTOANAL INHIBITION AND INCONTINENCE IN PATIENTS WITH RECTAL PROLAPSE

Thirty-five patients with complete rectal prolapse, 32 with neurogenic faecal incontinence and 33 controls underwent ambulatory recording using a computerized anal electromyographic and anorectal manometry system. Median resting anal pressures were 34 cmH(2)O in patients with prolapse, 51 cmH(2)O in those with neurogenic faecal incontinence and 94 cmH(2)O in controls. Median basal rectal pressures were 18, 21 and 21 cmH(2)O respectively. High-pressure rectal waves of median amplitude 71 cmH(2)O lasting 30-150s and associated with inhibition of the electromyographic activity of the internal anal sphincter and a fall in anal pressures were seen in all patients with prolapse but not in controls or those with neurogenic incontinence. These waves were abolished following successful resection rectopexy. Recovery of continence occurs by abolition of high-pressure rectal waves, which produce maximal inhibition of sphincter activity before operation.