title: Evaluation of nasolacrimal fluorescein transit time in ophthalmically normal dogs and nonbrachycephalic cats.
abstract: OBJECTIVE
  To evaluate fluorescein nasolacrimal transit (NLT) times in ophthalmically normal dogs and nonbrachycephalic cats by use of 2 methods of the Jones test.
  
  
  METHODS
  73 dogs and 36 cats.
  
  
  METHODS
  Fluorescein dye was applied to the ocular surface of both eyes by means of a wetted fluorescein strip and, in a subsequent test, by administration of a drop of 0.2% fluorescein solution. During each test, the nares were monitored for the appearance of fluorescein for up to 30 minutes after application. Time of fluorescein appearance at the nares was recorded as NLT time. Recorded variables for all study animals included age, reproductive status, body weight, and Schirmer tear test values. For dogs, skull index, snout length, and cephalic conformation were also recorded. Data were grouped for statistical comparisons according to test results.
  
  
  RESULTS
  In both dogs and cats, NLT was faster when the fluorescein solution versus fluorescein strip was used. In cats, none of the recorded variables had a significant effect on NLT, irrespective of the testing method used. In dogs, several variables had a significant effect on NLT, including cephalic conformation, snout length, age, and reproductive status, but these findings varied with testing method and testing group.
  
  
  CONCLUSIONS
  NLT was highly variable in dogs and cats, regardless of testing method used. Assessment of nasolacrimal patency in brachycephalic dogs by use of either method evaluated here is not likely to be clinically useful. In cats, assessment of nasolacrimal patency with the fluorescein drop method was faster and more conclusive than with the fluorescein strip method.
authors.affiliation: Department of Small Animal Clinical Sciences, Virginia-Maryland Regional College of Veterinary Medicine, Virginia Tech and University of Maryland, Blacksburg, VA 24061, USA.
authors.forename: Daniel R
authors.initials: DR
authors.lastname: Binder
authors.forename: Ian P
authors.initials: IP
authors.lastname: Herring
mesh_terms: D000818:Animals; D049628:Body Size; D001835:Body Weight; D002415:Cats; D004285:Dogs; D019793:Fluorescein / Q000493:pharmacokinetics*; D009301:Nasolacrimal Duct / Q000378:metabolism*; D010052:Ovariectomy; D012016:Reference Values; D012886:Skull / Q000033:anatomy & histology
chemical_list: D019793:Fluorescein