Different anal pressure profiles in patients with anal fissure

Abstract

Background: A consistent debate exists about the association between anal fissure and hypertonic anal canal. The aim of this study was to determine if the manometric findings in patients with chronic anal fissures varied according to the topography of the fissure.

Patients and methods: Seventy-three outpatients (52 men, 71%) with chronic anal fissures and nine healthy volunteers (5 men, 55%) were examined. Patients were classified according to the topography of the anal fissures: posterior midline (group A), anterior midline (group B), and lateral position (group C). We use computerized anorectal manometry to evaluate anal resting pressure, maximal voluntary contraction, recto-anal inhibitory reflex, rectal sensations and rectum compliance.

Results: In Group A, the mean pressure was higher than that of controls (p<0.05), and the resting pressure 2 cm from anal verge was higher than that of other groups and controls (p<0.05). Normotonic anal canal was found in 49.1% of patients in group A, in 66% of those in group B and in 57.1% of those in group C. Four elderly patients (7%) of group A had a hypotonic anal canal. No differences were found regarding maximal voluntary contraction, recto-anal inhibitory reflex, rectal sensations and rectum compliance between patients and controls.

Conclusions: Patients with chronic anal fissures may have several anal pressure profiles. The anal canal is often normotonic. Fissures with hypertonic or normo-hypotonic anal canal need different therapies.