Expert: Jessica - 7/16/2009

Question
Hey im asking this question because my cats eye has been funny for the past 2 days , ive read similar questions and maybe it's the same as his third eye lid covering it its grey/green looking or kinda white its stuck over almost 2 thirds of his eye , im concerned and i will see the vet tommorow but to ease my mind i would like to hear other thoughts

Answer
Hi Ryan.  It does sound like this is what you're seeing.  The third eyelid, also called the nictitating membrane or "haw", begins at the inside corner of the cat's eye and sweeps vertically across the cat's eyeball, usually when the outer eyelids are closed.  If the eye becomes infected, injured, or irritated by a foreign object, the third eyelid may stay exposed, even when the outer eyelids are open.  

When diagnosed promptly, most problems which cause the third eyelid to become exposed are very treatable.  Eye infections or scratches generally require an eye ointment or eye drop that is applied several times daily.  Certain viral conditions are less treatable.  At times, scarring can occur and cause the third eyelid to adhere to the eyeball permanently.  This can impede the cat's vision but usually doesn't cause any pain.  However, these are not common compared to the typical eye infections (called conjunctivitis) that are caught and treated promptly.