Patient selection and treatment modalities for chronic anal fissure.

Background: Incontinence of feces or flatus is a serious complication of lateral internal sphincterotomy with a incidence of 0-35%. Multiple cofactors may predispose to fecal incontinence.

Methods: Review of 27 reported series of internal sphincterotomy and analysis of 34 consecutive cases of fecal incontinence seen by the author were carried out. Reports of the effect of topical nitroglycerin or botulinum toxin on the anal sphincter are discussed and supplemented by the author's experience.

Results: Reported postoperative incidence of incontinence to feces or flatus is remarkably variable (0-35%). Multiple factors (eg, multiparity, age, constipation, and previous surgery) were identified in each of the author's cases of incontinence. Pharmacologic sphincterotomy reliably relieves sphincter spasm and may promote healing.

Conclusions: Reappraisal of current standard treatment of anal fissure is warranted. Many preexisting, possibly predisposing, factors should be considered when deciding on treatment. Pharmacological sphincterotomy requires further clinical study. New nonsurgical modalities should be included in the treatment algorithm.