title: A new method for hemorrhoid surgery: experimental model of diode laser application in monkeys.
abstract: OBJECTIVE
  Detailed here is an experimental model in monkeys of a new approach to treat hemorrhoids using a diode laser.
  
  
  BACKGROUND
  Hemorrhoids are a common source of pain and suffering. Endovascular laser therapy for variceal veins is a method that potentially could be used in the treatment of hemorrhoids. There is currently no such method described in the literature.
  
  
  METHODS
  Hemorrhoids were induced in monkeys by ligation of the inferior hemorrhoidal vein, similar to their cause in humans. After the piles were identified, laser fibers were introduced into them, and they were irradiated with laser energy (810 nm at 1-2 W in 1-sec pulses of 1-2 J each, for a total fluency of 4-10 J).
  
  
  RESULTS
  The piles were completely reduced, and histological examination performed 10 d post-surgery showed reduction of the dilated vessels and complete healing. The laser energy was not delivered directly into the veins, but instead to the surrounding submucosal interstitial tissue, effectively reducing the hemorrhoids.
  
  
  CONCLUSIONS
  The diode laser energy delivered into the hemorrhoids led to their complete resolution. Further clinical trials using this protocol must be carried out to determine its applicability to human hemorrhoids.
authors.affiliation: Department of Surgery, Universidade Federal de São Paulo, São Paulo, Brazil. helio@plapler.com.br
authors.forename: Hélio
authors.initials: H
authors.lastname: Plapler
mesh_terms: D016342:Angioplasty, Laser / Q000379:methods*; D000818:Animals; D004195:Disease Models, Animal; D000882:Haplorhini; D006484:Hemorrhoids / Q000209:etiology / Q000473:pathology / Q000601:surgery*; D017075:Laser Coagulation / Q000379:methods*; D054023:Lasers, Semiconductor; D008297:Male