title: Transnasal, Endoscopically Guided Skull-Based Surgery by Pharyngotomy for Mass Removal from the Sphenopalatine Sinus in a Horse.
abstract: OBJECTIVE
  To report a transnasal, endoscopically guided ventral surgical approach for accessing the cranial and caudal segments of the sphenopalatine sinus for mass removal in a horse.
  
  
  METHODS
  Case report.
  
  
  METHODS
  Adult horse with acute onset blindness referable to a soft tissue mass within the sphenopalatine sinus.
  
  
  METHODS
  A 7-year-old Warmblood gelding presented with a history of running into a fence and falling. No neurologic signs were identified at initial examination but acute blindness was noted 3 weeks later. On computed tomography (CT) the sphenopalatine sinus was filled with a large homogeneous mass with poor contrast enhancement that extended dorsally with thinning to the dorsal cortex of the sphenoid bone, just rostral to the entrance of the optic canals into the cranial cavity. Surgical access to the sphenopalatine sinus was achieved using a transnasal, endoscopically guided ventral pharyngotomy approach and the mass lesion was removed. A presumptive diagnosis of chondroma was made based on histopathology. The horse recovered well from surgery, and although it has not regained vision as of 6.5 years postoperatively, the disease has not progressed.
  
  
  CONCLUSIONS
  Transnasal, endoscopically-guided ventral surgical access to the sphenopalatine sinus is possible in horses and may improve access in horses with disease extending caudally beyond the palatine portion of the sinus. Use of smaller diameter or specialized instruments, such as various endoscopic bone cutting instruments, and CT image guidance may improve sinus access by this route.
authors.affiliation: Department of Clinical Sciences, College of Veterinary Medicine, Cornell University, Ithaca, New York. rmr45@cornell.edu.
authors.forename: Rolfe M
authors.initials: RM
authors.lastname: Radcliffe
authors.affiliation: Department of Clinical Sciences, College of Veterinary Medicine, Cornell University, Ithaca, New York.
authors.forename: Yasmine
authors.initials: Y
authors.lastname: Messiaen
authors.affiliation: Department of Clinical Sciences, College of Veterinary Medicine, Cornell University, Ithaca, New York.
authors.forename: Nita L
authors.initials: NL
authors.lastname: Irby
authors.affiliation: Department of Clinical Sciences, College of Veterinary Medicine, Cornell University, Ithaca, New York.
authors.forename: Thomas J
authors.initials: TJ
authors.lastname: Divers
authors.affiliation: Department of Clinical Sciences, College of Veterinary Medicine, Cornell University, Ithaca, New York.
authors.forename: Curtis W
authors.initials: CW
authors.lastname: Dewey
authors.affiliation: Department of Clinical Sciences, College of Veterinary Medicine, Cornell University, Ithaca, New York.
authors.forename: Katharyn J
authors.initials: KJ
authors.lastname: Mitchell
authors.affiliation: Department of Clinical Sciences, College of Veterinary Medicine, Cornell University, Ithaca, New York.
authors.forename: Lauren V
authors.initials: LV
authors.lastname: Schnabel
authors.affiliation: Department of Clinical Sciences, College of Veterinary Medicine, Cornell University, Ithaca, New York.
authors.forename: Abraham J
authors.initials: AJ
authors.lastname: Bezuidenhout
authors.affiliation: Department of Clinical Sciences, College of Veterinary Medicine, Cornell University, Ithaca, New York.
authors.forename: Peter V
authors.initials: PV
authors.lastname: Scrivani
authors.affiliation: Department of Clinical Sciences, College of Veterinary Medicine, Cornell University, Ithaca, New York.
authors.forename: Norm G
authors.initials: NG
authors.lastname: Ducharme
mesh_terms: D000818:Animals; D002812:Chondroma / Q000175:diagnosis / Q000601:surgery / Q000662:veterinary*; D004724:Endoscopy / Q000662:veterinary; D006734:Horse Diseases / Q000175:diagnosis / Q000601:surgery*; D006736:Horses; D008297:Male; D010611:Pharyngectomy / Q000379:methods / Q000662:veterinary*; D012886:Skull / Q000601:surgery*