Various metabolic, infectious, and immune-mediated diseases as well as hypertension and neoplasia may manifest with ocular signs. Here's a rundown as a reminder when you're looking into your patients' peepers.
Diabetes mellitus. In comparison to dogs, cats have relatively few ocular complications related to diabetes. The most common complication in dogs is the rapid development of bilateral cataracts. Initially, vacuoles form along the equator of the lens, which progress into the anterior and posterior cortex. This rapid cataract development can lead to severe lens-induced uveitis. In addition, diabetic dogs have been shown to be at a higher risk for keratoconjunctivitis sicca and have reduced corneal sensitivity.
Hyperadrenocorticism. Many ocular lesions have been associated with hyperadrenocorticism in dogs. Surface lesions include progressive and nonhealing corneal ulceration, corneal degeneration, and keratoconjunctivitis sicca. Intraocular lesions include lipemic aqueous humor, lipemia retinalis, and hypertensive chorioretinopathy. Also keep in mind that dogs with hyperadrenocorticism suffer from sudden acquired retinal degeneration more commonly than unaffected dogs do.
Hypothyroidism. Ocular manifestations of hypothyroidism in dogs can result from hyperlipidemia leading to corneal lipid dystrophy, lipemic aqueous humor, and uveitis or lipemia retinalis with retinal bleeding and retinal detachment. Affected dogs are also more likely to suffer from nonhealing corneal erosions.