title: Evaluation of the effects of transendoscopic diode laser palatoplasty on clinical, histologic, magnetic resonance imaging, and biomechanical findings in horses.
abstract: OBJECTIVE
  To determine the effects of diode laser palatoplasty on the soft palate in horses.
  
  
  METHODS
  6 clinically normal horses and 6 euthanized horses from another study.
  
  
  METHODS
  6 horses underwent diode laser palatoplasty (treated horses); 3 received low-dose laser treatment (1,209 to 1,224 J), and 3 received high-dose treatment (2,302 to 2,420 J). Six other horses received no treatment (control horses). The upper respiratory tracts of all treated horses were evaluated immediately following surgery (day 0) and on days 2, 7, 14, 21, 30, and 45. Horses were euthanized on day 45, and magnetic resonance imaging (MRI) of the head was performed. The soft palate was removed from treated and control horses, evaluated grossly, and scored for edema, inflammation, and scarring. Soft palates from all horses were sectioned for histologic and biomechanical evaluations.
  
  
  RESULTS
  Endoscopic examination revealed a significant increase in soft palate scarring and decrease in edema and inflammation in treated horses by day 7. Gross postmortem findings corresponded with MRI findings. Gross and histologic examination revealed a significant increase in scarring, edema, and inflammation at day 45. Histologic evaluation of palatal tissue from high-dose-treated horses revealed full-thickness injury of skeletal muscle, with atrophy of muscle fibers; findings in low-dose-treated horses indicated superficial injury to skeletal muscle. After surgery, treated horses had a significant decrease in soft palate elastic modulus, compared with control horses.
  
  
  CONCLUSIONS
  Laser palatoplasty resulted in soft palate fibrosis and skeletal muscle loss; however, the fibrosis did not result in an increase in soft palate elastic modulus.
authors.affiliation: Department of Veterinary Clinical Sciences, School of Veterinary Medicine, Purdue University, West Lafayette, IN 47907, USA. kdelfs@purdue.edu
authors.forename: Kira C
authors.initials: KC
authors.lastname: Alkabes
authors.forename: Jan F
authors.initials: JF
authors.lastname: Hawkins
authors.forename: Margaret A
authors.initials: MA
authors.lastname: Miller
authors.forename: Eric
authors.initials: E
authors.lastname: Nauman
authors.forename: William
authors.initials: W
authors.lastname: Widmer
authors.forename: Doug
authors.initials: D
authors.lastname: Dunco
authors.forename: Jeffery
authors.initials: J
authors.lastname: Kras
authors.forename: Laurent
authors.initials: L
authors.lastname: Couetil
authors.forename: Timothy
authors.initials: T
authors.lastname: Lescun
authors.forename: Raju
authors.initials: R
authors.lastname: Gautam
mesh_terms: D000273:Adipose Tissue / Q000473:pathology; D000375:Aging / Q000502:physiology; D000818:Animals; D001696:Biomechanical Phenomena; D002972:Cleft Palate / Q000473:pathology / Q000601:surgery* / Q000662:veterinary; D004724:Endoscopy / Q000379:methods / Q000662:veterinary; D005065:Euthanasia; D006734:Horse Diseases / Q000473:pathology / Q000601:surgery*; D006736:Horses; D008279:Magnetic Resonance Imaging; D010160:Palate, Soft / Q000473:pathology / Q000502:physiology / Q000503:physiopathology / Q000601:surgery; D012016:Reference Values; D014741:Video Recording