Surgical treatment of chronic fissure-in-ano: a prospective randomised study.

A prospective randomised study compared anal dilatation (n = 37), posterior internal sphincterotomy (n = 21) and lateral sphincterotomy (n = 20) in the surgical treatment of chronic anal fissures in 78 consecutive patients. All the operations were performed under general anaesthesia using standard techniques. Anal dilatation relieved anal pain early (immediate relief in 57% of patients; the mean pain-days +/- SD of 3.2 +/- 5.4 days). Anal fissures after this operation healed in a mean time +/- SD of 20.3 +/- 12.5 days, coming in second place to lateral sphincterotomy. Anal dilatation was followed by insignificant wound infection but its main disadvantage was a high rate of post operative anal incontinence (in 24.3% of patients). Fissurectomy and posterior internal sphincterotomy was followed by the longest period of post operative anal pain (mean +/- SD of 32.4 +/- 10 days) as compared to the other two operations. It was the least favourable operation. Lateral sphincterotomy was followed by early relief of pain (immediate relief in 95% of patients). It was not followed by wound infection. It had the quickest healing time for the fissures (a mean +/- SD of 14.7 +/- 8.7 days). It was followed by anal incontinence in only one patient. In conclusion lateral sphincterotomy was the most favourable operation and it is perhaps the operation of choice to perform in patients with chronic anal fissures needing surgical treatment.