Rectocele Repair with or Without Internal Sphincter Botulinum Toxin Injection: a Prospective Randomized Trial

100 units of lyophilized botulinum toxin type A were diluted in saline to 50 U/mL before the injections. A total of 30 units of type-A botulinum toxin was injected with a 22-G needle evenly divided in 3 sites, 2 on either side of the internal anal sphincter (3 and 9 O'clock) and the third anteriorly (at 12 O'clock)

A total of 30 units of distilled water was injected with a 22-G needle evenly divided into 3 sites, 2 on either side of the internal anal sphincter (3 and 9 O'clock) and the third anteriorly (at 12 O'clock)