Meta-analysis of operative techniques for fissure-in-ano

PURPOSE: Operative techniques commonly used for fissure-in-ano include anal stretch, open lateral sphincterotomy, closed lateral sphincterotomy, poste rior midline sphincterotomy, and to a lesser extent dermal flap coverage of the fissure. Reports of direct comparisons among these techniques are vari able in their results and for the most part underpowered. A rigorous analys is of the combined reports was therefore undertaken to determine whether a preferred technique for fis sure surgery can be elucidated. METHODS: MEDLIN E was searched for all published reports using the key words "surgery" and "anal fissure." All reports in which there was a direct comparison between at least two operative techniques were reviewed, and when more than one rep ort existed for any given pair, that report was included in the meta-analys is. If crude data were not presented in the report, the authors were contac ted, and crude data mere obtained. The two most commonly used end points in these reports were persistence of the fissure and postoperative incontinen ce of flatus. These are the only two end points included in the meta-analys is. The meta-analysis was performed using Epi-Info software obtained from t he Centers for Disease Control and Prevention (www.cdc.gov). RESULTS: Seven teen publications fulfilled the criteria of the study, encompassing 2,727 p atients. Significant differences were found for both persistence and incont inence to flatus when comparing anal stretch to all forms of sphincterotomy . No significant difference was found comparing open to closed lateral inte rnal sphincterotomy for persistence or incontinence. Posterior midline sphi ncterotomy was not significantly different from lateral sphincterotomy rela ted to persistence or incontinence. CONCLUSION: Internal anal sphincterotom y is superior to anal stretch and should probably be performed in the later al location, although both the open and closed techniques seem equally effi cacious.