Therapy for a blind pet always depends first on establishing the correct diagnosis. There are numerous possible causes for blindness, and it is essential to identify the specific cause to initiate appropriate treatment.
CausesBlindness can be caused by many different conditions, including:
Severe entropion, which is inversion or an inward rolling of the eyelid margins, or heavy facial folds and brows – especially a problem in the shar-pei and chow-chow breeds
Keratoconjunctivitis sicca (dry eye syndrome) with resultant corneal scarring, blood vessel in-growth, and pigment deposition on the corneal surface
Corneal endothelial degeneration, which is degenerative disease of the inner lining of the cornea. Degeneration results in an opaque, bluish appearance of the cornea.
Severe pannus, also called chronic superficial keratitis, that results in dramatic blood vessel infiltration and scarring of the cornea in German shepherd and German shepherd-cross dogs
Severe uveitis due to an immune-mediated disease; a systemic bacterial, viral, protozoal or fungal infection; or a tumor
Hyphema (blood in the anterior chamber) secondary to ocular trauma, a blood clotting disorder or systemic hypertension (high blood pressure)
Cataract (dense opacity in the lens) formation
Lens luxation (displacement) with secondary glaucoma
Glaucoma, which is sustained elevated pressures within the eye due to inadequate fluid drainage from the eye, resulting in damage to the optic nerve
Progressive retinal degeneration, an inherited condition in many purebred dogs
Chorioretinitis (inflammation of the choroid and retina) secondary to an immune-mediated disease; a bacterial, viral, protozoal, fungal or parasitic infection; tumor
Retinal detachment secondary to a congenital malformation of the retina; a bacterial, viral, protozoal, fungal or parasitic infection; systemic hypertension; tumor
Retinal degeneration from nutritional deficiencies of vitamin A and/or vitamin E (rare)
Sudden acquired retinal degeneration (SARD), a disease of unknown cause that results in complete dysfunction of the retinal photoreceptors (rods and cones)
Congenital underdevelopment of the optic nerves (very rare)
Encephalitis (inflammation of the brain) or meningoencephalitis (inflammation of the brain and the membranes that cover it) due to a viral, protozoal, fungal or bacterial infection, or from a granulomatous type of inflammation
Neoplasia (tumor) involving the optic chiasm (location in the brain where both optic nerves meet and cross) or optic pathways with in the brain
Neoplasia involving the occipital cortex (visual center of the brain)
Hydrocephalus (fluid accumulation within the skull compressing the brain)
Hypoxia (inadequate oxygen supply to the brain) resulting in permanent brain injury
Cerebral vascular infarct (occlusion of a blood vessel in the brain) resulting in brain injury
Head trauma with edema and hemorrhage
Traumatic avulsion (tearing away)of the optic nerves from the optic chiasm or from behind the eye
Hepatic encephalopathy (severe liver disease causing abnormal neurologic signs including disorientation and stupor) or severe hypoglycemia (low blood sugar) imitating vision loss
Certain toxins, such as lead poisoning
