T.J. Dunn Jr., DVM
Have you ever wondered what makes smoe dogs' eyes seem cloudy? You aren't alone. A common query veterinarians hear goes like this: "What's that hazy look in her eyes, Doctor? Is she getting glaucoma or cataracts?" The answer is unique for each patient because there is a variety of ocular disorders, some innocuous and some rather critical, that are first noticed and described as hazy or cloudy eyes.
During an ocular evaluation, the doctor categorizes the potential causes for hazy eyes into three main types. The problem could originate in the cornea, the lens or the aqueous humor (the transparent fluid that fills the two chambers behind the cornea and in front of the lens). Easiest to recognize are the superficial problems associated withthe cornea, the glass-like dome of transparent tissue at the front-central portion of the eye. The cornea, only about 3/4 mm thick, is a specialized extension of the "white of the eye," called the sclera, and assists in maintaining the glove's shape, intraocular pressure and diffraction of light entering the eye.
Any disruption of the surface epithelium (often called a corneal ulcer) will alter the cornea's normal state of dehydration. Other common causes of haziness are trauma, viral infections, immune-mediated infiltrates of the cornea, liver trouble, and intraocular stresses such as glaucoma. Once the surface layer is damaged or stretched, the cornea loses its ability to maintain the water and protein ratios within it, and the cornea will overhydrate and swell. The influx of water separates the delicate cell's layers and throws the corneal proteins into disarray. Light no longer passes unimpeded through the now hazy-blue or whitish cornea. Call the veterinarian right away!
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