title: Association of height, body weight, age, and corneal diameter with calculated intraocular lens strength of adult horses.
abstract: OBJECTIVE
  To determine whether differences exist in the calculated intraocular lens (IOL) strengths of a population of adult horses and to assess the association between calculated IOL strength and horse height, body weight, and age, and between calculated IOL strength and corneal diameter.
  
  
  METHODS
  28 clinically normal adult horses (56 eyes).
  
  
  METHODS
  Axial globe lengths and anterior chamber depths were measured ultrasonographically. Corneal curvatures were determined with a modified photokeratometer and brightness-mode ultrasonographic images. Data were used in the Binkhorst equation to calculate the predicted IOL strength for each eye. The calculated IOL strengths were compared with a repeated-measures ANOVA. Corneal curvature values (photokeratometer vs brightness-mode ultrasonographic images) were compared with a paired t test. Coefficients of determination were used to measure associations.
  
  
  RESULTS
  Calculated IOL strengths (range, 15.4 to 30.1 diopters) differed significantly among horses. There was a significant difference in the corneal curvatures as determined via the 2 methods. Weak associations were found between calculated IOL strength and horse height and between calculated IOL strength and vertical corneal diameter.
  
  
  CONCLUSIONS
  Calculated IOL strength differed significantly among horses. Because only weak associations were detected between calculated IOL strength and horse height and vertical corneal diameter, these factors would not serve as reliable indicators for selection of the IOL strength for a specific horse.
authors.affiliation: Department of Veterinary Clinical Sciences, College of Veterinary Medicine, Purdue University, West Lafayette, IN 47907, USA.
authors.forename: Meredith C
authors.initials: MC
authors.lastname: Mouney
authors.forename: Wendy M
authors.initials: WM
authors.lastname: Townsend
authors.forename: George E
authors.initials: GE
authors.lastname: Moore
mesh_terms: D000367:Age Factors; D000818:Animals; D001699:Biometry; D001835:Body Weight; D003315:Cornea / Q000033:anatomy & histology / Q000000981:diagnostic imaging; D003941:Diagnostic Techniques, Ophthalmological / Q000662:veterinary; D005260:Female; D006736:Horses / Q000033:anatomy & histology* / Q000502:physiology* / Q000601:surgery; D019654:Lens Implantation, Intraocular / Q000662:veterinary; D007910:Lenses, Intraocular / Q000592:standards* / Q000662:veterinary; D008297:Male; D018918:Phacoemulsification / Q000662:veterinary; D012030:Refractive Errors / Q000628:therapy* / Q000662:veterinary; D014463:Ultrasonography / Q000662:veterinary