Effectiveness of combined botulinum toxin and fissurectomy on chronic anal fissures - a systematic review.

Background: Anal fissures are a debilitating benign condition, thought to be due to the hypertonicity of the internal anal sphincter resulting in localized ischaemia inhibiting healing. There are several surgical and non-surgical treatment options for chronic anal fissures. Clinical practice surveys report a trend toward sphincter-sparing options, reserving the more successful treatment of lateral sphincterotomy, with an incontinence rate up to 10%, for refractory fissures.

Methods: A search of MEDLINE, Cochrane Database of Systematic Reviews and EMBASE for studies assessing sphincter-sparing treatment with botulinum toxin and fissurectomy was performed following PRISMA guidelines. Outcomes assessed included healing rate, persistence, recurrence, re-intervention and incontinence rates.

Results: Fifteen non-randomized studies assessed 978 patients managed with botulinum toxin and fissurectomy. The mean age was 40.8 years with a female predominance of 58.9%. Healing rate was reported on 14 of the 15 studies, with a healing rate of 81% (95% CI:0.67, 0.90). Persistence rate was reported as 15% (95% CI:0.07, 0.28) and a recurrence rate of 6% (95% CI: 0.01, 0.19). Re-intervention was required in 8% of patients with 55.1% requiring a repeat dose of botulinum toxin with or without fissurectomy. Incontinence appears to be transient with studies reporting a rate of 1% with median long-term follow up 23 months (range: 5-60 months).

Conclusion: Combination fissurectomy and botulinum toxin is a safe and viable sphincter sparing treatment option, with moderate success rate and negligible complications. Randomized controlled trials are required to further strengthen the evidence for its use in chronic anal fissures.