title: Transendoscopic laser treatment of rostral displacement of the palatopharyngeal arch in four horses.
abstract: OBJECTIVE
  To document the use and clinical outcome of transendoscopic laser techniques for treatment of rostral displacement of the palatopharyngeal arch (RDPA) in horses.
  
  
  BACKGROUND
  Rostral displacement of the palatopharyngeal arch is a rare cause of upper respiratory noise and exercise intolerance in horses, and may be associated with abnormal laryngeal anatomy. There are few reports of successful treatment of this condition, and no reports of the treatment of RDPA using laser techniques.
  
  
  METHODS
  The diagnosis of RDPA was based on the presence of palatal tissue covering the dorsal aspect of the arytenoid cartilages on endoscopic examination. Either a neodymium:yttrium aluminum garnet (Nd:YAG) laser noncontact technique (1060 nm, 100 W continuous mode) or a diode laser contact technique (808 nm, 14 W, continuous mode) was used.
  
  
  RESULTS
  In 3 horses in which the Nd:YAG laser was used, displaced palatal tissue was not fully divided at surgery, but separated after latent thermal necrosis within 3 days. In the horse in which the diode laser was used, tissues were fully divided at the time of surgery. Two horses had abnormal laryngeal anatomy and laryngeal hemiplegia. One of these 2 horses was subjected to arytenoidectomy, and had limited success as a race-horse, while the other was retired as a broodmare. One of 2 horses with no other laryngeal abnormalities raced once unsuccessfully, while the other horse was never raced.
  
  
  CONCLUSIONS
  Rostral displacement of the palatopharyngeal arch may be corrected in standing horses using transendoscopic surgery, but despite successful ablation of displaced tissue the prognosis for athletic performance is poor.
authors.affiliation: Department of Food Animal and Equine Medicine, College of Veterinary Medicine, North Carolina State University, Raleigh, North Carolina, USA. Anthony_Blikslager@ncsu.edu
authors.forename: A T
authors.initials: AT
authors.lastname: Blikslager
authors.forename: L P
authors.initials: LP
authors.lastname: Tate
authors.forename: R
authors.initials: R
authors.lastname: Tudor
mesh_terms: D000402:Airway Obstruction / Q000175:diagnosis / Q000209:etiology* / Q000503:physiopathology / Q000601:surgery*; D000818:Animals; D001193:Arytenoid Cartilage; D004724:Endoscopy / Q000379:methods*; D017079:Exercise Tolerance; D005260:Female; D006734:Horse Diseases / Q000175:diagnosis / Q000209:etiology* / Q000503:physiopathology / Q000601:surgery*; D006736:Horses; D053685:Laser Therapy / Q000379:methods*; D008297:Male; D010160:Palate, Soft / Q000002:abnormalities* / Q000601:surgery*; D010614:Pharynx / Q000002:abnormalities* / Q000601:surgery*; D011379:Prognosis; D012135:Respiratory Sounds / Q000209:etiology; D016896:Treatment Outcome