title: Schirmer tear tests and intraocular pressures in conscious and anesthetized koalas (Phascolarctus cinereus).
abstract: OBJECTIVE
  To estimate mean Schirmer tear test (STT) and intraocular pressure (IOP) values in healthy koalas both conscious and anesthetized.
  
  
  METHODS
  Data were gathered from koalas in Victoria, Australia. Conscious examinations were performed on captive koalas. Free-ranging (wild) koalas were examined under anesthesia. Anesthesia was induced using alfaxalone, and animals were maintained on oxygen and isoflurane if required. All animals were healthy and had no surface ocular pathology detectable during slit lamp biomicroscopy. STT I tests were performed using commercial STT test strips placed in the lower fornix for 1 min. IOP was measured using an applanation tonometer after topical anesthesia. The higher value of the two eyes for both STT and IOP was analyzed. STT was measured in 53 koalas (34 conscious, 19 anesthetized) and IOP was measured in 43 koalas (30 conscious, 13 anesthetized). A two-sample t-test was used to compare means. A P-value <0.05 was regarded as significant. Mean ± SD is presented.
  
  
  RESULTS
  The mean higher STT in conscious koalas was 10.3 ± 3.6 mm wetting/min and in anesthetized koalas it decreased to 3.8 ± 4.0 mm wetting/min (P < 0.0001). The mean higher IOP in conscious koalas was 15.3 ± 5.1 mmHg, and in anesthetized koalas it was 13.8 ± 3.4 mmHg (P = 0.32). There was no effect of sex on either STT or IOP.
  
  
  CONCLUSIONS
  The mean and SD of STT and IOP values for koalas both conscious and anesthetized were reported. The mean STT was significantly reduced by alfaxalone anesthesia.
authors.affiliation: Animal Eye Care, 181 Darling Road, East Malvern, Victoria 3145, Australia. vetrg@aol.com
authors.forename: Rachael A
authors.initials: RA
authors.lastname: Grundon
authors.forename: Gary A
authors.initials: GA
authors.lastname: Anderson
authors.forename: Michael
authors.initials: M
authors.lastname: Lynch
authors.forename: Chlöe
authors.initials: C
authors.lastname: Hardman
authors.forename: Anu
authors.initials: A
authors.lastname: O'Reilly
authors.forename: Robin G
authors.initials: RG
authors.lastname: Stanley
mesh_terms: D000758:Anesthesia / Q000662:veterinary*; D000777:Anesthetics / Q000494:pharmacology*; D000818:Animals; D005260:Female; D007429:Intraocular Pressure / Q000502:physiology*; D008297:Male; D048368:Phascolarctidae; D012016:Reference Values
chemical_list: D000777:Anesthetics