Contributions of evacuation proctography and anorectal manometry to evaluation of adults with constipation and defecatory difficulty.

We prospectively evaluated 36 patients who complained of chronic constipation and/or defecatory difficulties to determine the role of anorectal manometry and evacuation proctography in delineating the pathogenesis of these complaints. Twenty patients with constipation also underwent a colonic transit study with radioopaque markers, which identified one group with normal transit (N = 10) and another with slow transit (N = 10). Nine of 36 patients (25%) had inappropriate puborectalis muscle contraction or exhibited weak expulsion efforts during evacuation proctography, and these correlated highly with poor rectal emptying of barium paste (20 +/- 6% vs 61 +/- 5% in patients with normal relaxation; P less than 0.01). However, poor rectal emptying did not correlate with the presence of high-grade intussusceptions, large rectoceles, anorectal angles at rest or with straining, rectal diameter, clinical features, or colonic transit. Moreover, abnormal expulsion patterns as seen with anorectal manometry correlated poorly with the presence of inappropriate puborectalis contraction and decreased rectal emptying by proctography. Although anatomic abnormalities occurred frequently in patients with constipation and/or defecatory difficulties, they were also prevalent in asymptomatic controls. In view of these findings, surgical intervention to correct anatomic abnormalities in patients with constipation and/or defecatory difficulties should be considered only with great caution.