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Grating Visual Acuity in phakic, aphakic, and pseudophakic Poodles.
Angélica M V Safatle1, Tatiana A de Moraes1, Ana R Eyherabide1
1Department of Surgery, School of Veterinary Medicine and Animal Science (FMVZ), São Paulo University, Sao Paulo, Brazil.
Veterinary Ophthalmology
|August 22, 2020
Summary
Visual evoked potentials (VEP) effectively measure grating visual acuity in Poodles. Intraocular lens implantation after cataract surgery improves vision in pseudophakic dogs to levels comparable to phakic dogs.
Area of Science:
- Veterinary Ophthalmology
- Ophthalmic Diagnostics
- Canine Vision Research
Background:
- Assessing visual acuity in dogs is crucial for diagnosing and managing ocular conditions.
- Phakic, aphakic, and pseudophakic states represent different physiological conditions affecting vision.
Purpose of the Study:
- To compare grating visual acuity (VA) using visual evoked potentials (VEP) in Poodles with different lens statuses.
- To evaluate the effectiveness of intraocular lens (IOL) implantation in restoring vision.
Main Methods:
- Thirty-six Poodle dogs were divided into phakic, aphakic, and pseudophakic groups (n=12 each).
- Grating visual acuity was measured in cycles per degree (cpd) using the Roland RETIport® electrodiagnosis system.
- Measurements were conducted in a dark room without mydriatics, sedatives, or anesthetics.
Main Results:
- Mean grating VA was 5.9 ± 1.0 cpd (phakic), 2.6 ± 0.7 cpd (aphakic), and 5.2 ± 1.1 cpd (pseudophakic).
- Aphakic eyes showed significantly lower VA compared to phakic and pseudophakic eyes (P < .05).
- No significant difference in VA was observed between phakic and pseudophakic eyes.
Conclusions:
- VEP is a valuable tool for assessing grating visual acuity in canines.
- IOL implantation following phacoemulsification significantly improves VA in pseudophakic eyes.
- Restored VA in pseudophakic eyes is comparable to that of normal phakic eyes.
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