title: Comparison of the diagnostic quality of computed tomography images of normal ocular and orbital structures acquired with and without the use of general anesthesia in the cat.
abstract: OBJECTIVE
  To compare the diagnostic quality of computed tomography (CT) images of normal ocular and orbital structures acquired with and without the use of general anesthesia in the cat.
  
  
  METHODS
  Eleven privately owned cats with nasal disease presenting to a single referral hospital.
  
  
  METHODS
  All cats received a complete ophthalmic examination. A 16 multislice helical CT system was utilized to acquire images of the skull and neck with and without the use of general anesthesia. Images were acquired before and after the administration of intravenous iodinated contrast. Images of normal ocular and orbital structures were evaluated via consensus by two board-certified radiologists. Visibility of ocular and orbital structures, degree of motion, and streak artifact were assessed and scored for each image set in the transverse, dorsal, and sagittal planes.
  
  
  RESULTS
  The use of general anesthesia did not significantly affect the diagnostic quality of images. No motion artifact was observed in any CT image. Streak artifact was significantly increased in scans performed in the transverse orientation but not in the dorsal orientation or sagittal orientation and did not affect the diagnostic quality of the images. Contrast enhancement did not significantly enhance the visibility of any ocular or orbital structures.
  
  
  CONCLUSIONS
  Diagnostic CT images of normal ocular and orbital structures can be acquired without the use of general anesthesia in the cat.
authors.affiliation: Department of Veterinary Clinical Medicine, University of Illinois Urbana-Champaign, 1008 W. Hazelwood Drive, Urbana, IL 61802, USA.
authors.forename: Sean P
authors.initials: SP
authors.lastname: Collins
authors.forename: Jodi S
authors.initials: JS
authors.lastname: Matheson
authors.forename: Ralph E
authors.initials: RE
authors.lastname: Hamor
authors.forename: Mark A
authors.initials: MA
authors.lastname: Mitchell
authors.forename: Amber L
authors.initials: AL
authors.lastname: Labelle
authors.forename: Robert T
authors.initials: RT
authors.lastname: O'Brien
mesh_terms: D000768:Anesthesia, General / Q000662:veterinary*; D000818:Animals; D002415:Cats / Q000033:anatomy & histology*; D005123:Eye / Q000033:anatomy & histology / Q000000981:diagnostic imaging*; D009915:Orbit / Q000033:anatomy & histology / Q000000981:diagnostic imaging*; D014057:Tomography, X-Ray Computed / Q000662:veterinary*
keywords: VetMouseTrap™; anesthesia; computed tomography; eye; feline; orbit