[Functional pathomechanisms of anal fissure].

In a prospective consecutive study of 40 patients with anal fissure we analysed the anal sphincter function at rest and rectal distension. Healthy persons with comparable age and sex distribution were controls. The anal pressures were registered with thin water perfused catheters (2 ml/min). Our patients with anal fissure showed significant elevation of anal pressures at rest along the whole length of anal canal. During rectal distension only the distal part of anal sphincter (up to a level of 2 cm from the anocutaneous line) showed a spasm with reduced relaxation. Our results are useful for operative therapy, since lateral internal sphincterotomy corresponds very well to functional pathomechanism of anal fissure.