title: Preventive effect of botulinum toxin A in microanastomotic thrombosis: a rabbit model.
abstract: BACKGROUND
  Microvascular free tissue transfers play an important role in the reconstruction of body defects. Various aetiologies lead to vascular thrombosis and free-flap failure. In this study, the effects of botulinum toxin A on vessel diameters and prevention of anastomotic thrombosis were studied in a blinded vasospasm model in rabbits.
  
  
  METHODS
  One side of 16 adult rabbit ears was pre-treated with botulinum toxin type A, and normal saline injections were performed as control in the contralateral side. Seven days later, vessel diameters were measured in both the groups; the vessels were then cut and reanastomosed after vasospastic challenge and vessel patencies were evaluated.
  
  
  RESULTS
  Both artery and vein diameters were significantly larger in the botulinum toxin A group (P=0.002 and < 0.001, respectively). The patency rate of arterial and venous anastomosis was significantly higher in the neurotoxin pre-treated group (P=0.038 and 0.003, respectively).
  
  
  CONCLUSIONS
  This study shows that pre-treatment with botulinum toxin type A is associated with a lower rate of arterial and venous thrombosis in rabbit-model microanastomosis. Further studies are necessary to evaluate its ability to decrease vasospasm and thrombosis in free-flap survival of humans.
authors.affiliation: Division of Plastic and Reconstructive Surgery, Imam Hospital Complex, Tehran University of Medical Sciences, Tehran, Iran.
authors.forename: Mehdi
authors.initials: M
authors.lastname: Fathi
authors.forename: Hamidreza
authors.initials: H
authors.lastname: Fathi
authors.forename: Mehdi
authors.initials: M
authors.lastname: Mazloumi
authors.forename: Omid
authors.initials: O
authors.lastname: Khalilzadeh
authors.forename: Saeid
authors.initials: S
authors.lastname: Amanpour
authors.forename: Alipasha
authors.initials: A
authors.lastname: Meysamie
authors.forename: Leila
authors.initials: L
authors.lastname: Mashali
authors.forename: Mohammad H
authors.initials: MH
authors.lastname: Kardar
mesh_terms: D000714:Anastomosis, Surgical; D000818:Animals; D019274:Botulinum Toxins, Type A / Q000494:pharmacology*; D004195:Disease Models, Animal; D011183:Postoperative Complications / Q000517:prevention & control*; D011817:Rabbits; D011897:Random Allocation; D013524:Surgical Flaps / Q000098:blood supply; D013927:Thrombosis / Q000209:etiology / Q000517:prevention & control*
chemical_list: D019274:Botulinum Toxins, Type A