Botulinum toxin vs. topical glyceryl trinitrate ointment for pain control in patients undergoing hemorrhoidectomy: a randomized trial.Rosalia Patti, Piero Luigi Almasio, +4 authors Gaetano Giuseppe Di VitaDiseases of the colon and rectum2006PURPOSE The maximum resting pressure in the anal canal is greatly raised after hemorrhoidectomy. This increase is likely to be the cause of postoperative pain, which is still the most troublesome… (More)