Comparative Study between Closed versus Open Lateral Internal Sphincterotomy in the Treatment of Chronic Anal Fissure

Abstract

Chronic anal fissure is a common benign anorectal condition associated with severe pain,
bleeding, and significant impairment in quality of life. When conservative management fails,
LIS (Lateral Internal Sphincterotomy) is considered the gold standard surgical treatment. Two
techniques- OLIS (Open Lateral Internal Sphincterotomy) and CLIS (Closed Lateral Internal
Sphincterotomy)-are widely practiced, yet debate continues regarding their relative efficacy
and postoperative outcomes. This study was undertaken to compare early and short-term
outcomes of open versus closed LIS in patients with chronic anal fissure.