Medical treatment of chronic anal fissure. where do we stand on reversible chemical sphincterotomy?

Anal fissure is a common problem which can evolve to chronicity. Chronic anal fissure is thought to be an ischemic ulceration related to sphincter hypertonia. Lateral internal sphincterotomy, the most common treatment for chronic anal fissure, may cause permanent injury to anal sphincter leading to fecal incontinence. To avoid such side effect were developed medications producing a temporary or reversible sphincterotomy reducing the sphincter pressure only until the fissure has healed: nitrates, calcium channel antagonists and botulinum toxin. Authors aimed to summary the state of research on such treatments (efficacy, side effects, recurrence risk) and to clarify the role of these different medical options in the current treatment of chronic anal fissure.