Editing Fissure-in-ano (section)

=== Second-line: (once failed GTN) ===

** Botox injection. Inject to inter-sphincteric plane, away from the fissure, usually at 3 and 9 o'clock, although opinions vary - some say also anterior. Works in 50%, but recurrence rates at 1 year approach 50%. Can get transient incontinence, haematoma or sepsis, but unusual.
*** Cameron's suggests 20 units at 10 and 2 o'clock anteriorly in the inter-sphincteric groove. Sabiston's just says 20-100IU. UTD says it varies depending on preparation of botox used. I think 40 units on each side is a reasonable average.
*** Typically gives relaxation for three months
*** Can be done in office, or with a bit of sedation
*** Costs up to $600 for patients if they have to pay