## Overview Cataracts are opacities of the lens that interfere with light reaching the retina. In adult horses the majority are secondary to equine recurrent uveitis. Congenital and juvenile cataracts also occur and may have a genetic component in some breeds, notably Standardbreds. Severity ranges from small incidental opacities to complete blindness. ## Causes Equine recurrent uveitis is the leading cause in adults. Congenital cataracts may be inherited or developmental. Trauma and aging contribute additional cases. ## Diagnosis Ophthalmic examination with pupil dilation reveals the lens opacity. Associated signs of uveitis (synechiae, aqueous flare) are commonly present. Electroretinography may be performed before surgery to confirm retinal function. ## Treatment Small, non-progressive cataracts may be monitored. Vision-impairing cataracts are treated by surgical lens removal (phacoemulsification). Control of underlying uveitis is essential before and after surgery. ## Recovery and Prognosis Many horses regain useful vision after uncomplicated cataract surgery. Pre-existing uveitis, retinal detachment, or glaucoma worsen the outlook. Some horses return to athletic use. ## Prevention Prompt treatment of uveitis reduces secondary cataract formation. Breeding decisions may eventually be informed by genetic research in predisposed breeds.
cloudiness in the eye; vision impairment or spooking; bumping into objects; signs of uveitis such as squinting or tearing
## Overview Cataracts are opacities of the lens that interfere with light reaching the retina. In adult horses the majority are secondary to equine recurrent uveitis. Congenital and juvenile cataracts also occur and may have a genetic component in some breeds, notably Standardbreds. Severity ranges from small incidental opacities to complete blindness. ## Causes Equine recurrent uveitis is the leading cause in adults. Congenital cataracts may be inherited or developmental. Trauma and aging contribute additional cases. ## Diagnosis Ophthalmic examination with pupil dilation reveals the lens opacity. Associated signs of uveitis (synechiae, aqueous flare) are commonly present. Electroretinography may be performed before surgery to confirm retinal function. ## Treatment Small, non-progressive cataracts may be monitored. Vision-impairing cataracts are treated by surgical lens removal (phacoemulsification). Control of underlying uveitis is essential before and after surgery. ## Recovery and Prognosis Many horses regain useful vision after uncomplicated cataract surgery. Pre-existing uveitis, retinal detachment, or glaucoma worsen the outlook. Some horses return to athletic use. ## Prevention Prompt treatment of uveitis reduces secondary cataract formation. Breeding decisions may eventually be informed by genetic research in predisposed breeds.
cloudiness in the eye; vision impairment or spooking; bumping into objects; signs of uveitis such as squinting or tearing