title: Effect of body position on intraocular pressure in dogs without glaucoma.
abstract: OBJECTIVE
  To determine the effects of body position on intraocular pressure (IOP) in dogs without glaucoma.
  
  
  METHODS
  24 healthy dogs with no evidence of glaucoma.
  
  
  METHODS
  Dogs underwent ophthalmic examinations to ensure that no IOP-affecting ocular diseases were present. Each dog was sequentially placed in dorsal recumbency, sternal recumbency, and sitting position. For each of the 3 positions, IOP in the right eye was measured by use of an applanation tonometer immediately after positioning (0 minutes) and after 3 and 5 minutes had elapsed. The initial body position was randomly assigned; each position followed the other positions an equal number of times, and IOP measurements were initiated immediately after moving from one body position to the next. Proparacaine hydrochloride (0.5%) was applied to the right eye immediately prior to IOP measurements.
  
  
  RESULTS
  Intraocular pressure was affected by body position. During the 5-minute examination, IOP decreased significantly in dogs that were dorsally recumbent or sitting but did not change significantly in dogs that were sternally recumbent. For the 3 positions, overall mean IOP differed significantly at each time point (0, 3, and 5 minutes). Mean IOP in dorsal recumbency was significantly higher than that in sternal recumbency at 0 and at 3 minutes; although the former was also higher than that in sitting position at 3 minutes, that difference was not significant.
  
  
  CONCLUSIONS
  Body position affects IOP in dogs. When IOP is measured in dogs, body position should be recorded and consistent among repeat evaluations.
authors.affiliation: Department of Small Animal Clinical Sciences, Virginia-Maryland Regional College of Veterinary Medicine, Blacksburg, VA 24061, USA.
authors.forename: Joshua J
authors.initials: JJ
authors.lastname: Broadwater
authors.forename: Jamie J
authors.initials: JJ
authors.lastname: Schorling
authors.forename: Ian P
authors.initials: IP
authors.lastname: Herring
authors.forename: François
authors.initials: F
authors.lastname: Elvinger
mesh_terms: D000818:Animals; D004285:Dogs / Q000502:physiology*; D005260:Female; D007429:Intraocular Pressure / Q000502:physiology*; D008297:Male; D011187:Posture / Q000502:physiology*; D011897:Random Allocation; D012016:Reference Values; D014065:Tonometry, Ocular / Q000662:veterinary