Manometric assessment of continence after surgery for imperforate anus.

Of 49 children with imperforate anus, 23 underwent an abdominoperineal procedure for a high and seven for a low maliformation, 17 had a perineoplasty for a low and two for a high malformation. In each subject, rectal and anal sphincteric resting pressures were studied at least 1 yr after surgery. Of 30 subjects who had undergone an abdominoperineal procedure, eight were continent in contrast to 15 out of 19 patients who had had a perineoplasty (p less than 0.001). In patients who had undergone an abdominoperineal procedure, the rectal motility was of the colonic type, with waves of higher amplitude and lower frequency (p less than 0.01) than in the normal rectum in 23 cases and in most of these, peristalsis was recorded down to the anal margin. Incontinence was most frequently associated with abnormally short anal resistance, low anal pressure, reduced sensibility, weak voluntary contraction and absence of rectoanal inhibitory reflex. In the group of patients who underwent perineoplasty, continence was associated with normal mechanical parameters and normal physiologic behavior of the anal sphincter.