Refractive errors inmixed breed dogs ofdifferent ages.

Abstract

The purpose ofthe study was toevaluate the occurrence and range ofrefractive errors indogs ofdifferent ages. Atotal of99clinically healthy, mixed-breed mesocephalic dogs were included inthe study and divided into three different age groups according tothe current human/pet analogy chart: 40adults (23males, 17females, 1-8years old, 3-70kg), 21seniors (14males, 7females, 6-11years old, 7-42kg), and 38geriatrics (22males,16females, 8-13years old, 5-45kg). All the dogs underwent anophthalmic examination, including Schirmer tear test, tonometry, biomicroscopy, and ophthalmoscopy. Neither eye drops nor pharmacological sedatives were administered before the autorefractometry. The refractive states were assessed bilaterally using ahand-held Retinomax3 (Righton) autorefractor. The results underwent statistical analysis using Statistica v12 software (ANOVA and t-test). AP-value <0.05 was considered assignificant. Emmetropia, defined asarefractive state >-0.5D and < +0.5D, was found in36% ofthe adult, 43% ofthe senior, and 38% ofthe geriatric patients. Anisometropia was found in1% ofthe adult, 9.5% ofthe senior and 5.5% ofthe geriatric dogs when the refractive power ofthe two eyes differed ≥1.0 myopia ≤-0.5D and hyperopia ≥+0.5D were found in23% and 41% ofthe adult eye globes aswell as24% and 33% inthesenior dogs and 15% and 47% inthe geriatric dogs, respectively. The maximal values ofthemyopia intheadult and geriatric dogs were -2.5D and -2.75D, respectively. The maximal values ofthehyperopia intheadult and geriatric dogs were 1.75D and 2.5D, respectively. Nostatistically significant correlation was found between the groups. Ametropia isacommon refractive state for dogs ofdifferent ages. Themost frequent refractive state inametropic mixed-bed dogs inall age groups ishyperopia.