Conjunctivitis is the medical term for the inflammation of the tissue lining the eyelids. When inflammation occurs, excessive tear production makes excellent breeding ground for bacteria worsening the condition.
Causes of conjunctivitis include injuries, bacterial infections, viral infections, irritations, allergies, or foreign material (such as dirt, grass seeds, etc.) embedded in the eyelids.
Dogs and cats have three eyelids. These include an upper eyelid, lower eyelid, and the third eyelid, which is attached to the eye at the side closest to the nose, and then blinks out across the eye toward the ear. Many times, a foreign body, such as a grass seed, will get underneath that eyelid and cause the irritation.
Sedation is often necessary to allow adequate visual inspection under all three of the eyelids to help determine the cause of the problem. We must thoroughly examine the eye to determine the underlying root cause of the inflammation or the problem will recur.
Eye stains are used on the eye itself to confirm the presence or absence of any injury to the outer layer of the eye (cornea) itself.
It is important to do everything possible to determine the cause of the problem to prevent recurrence. Many times the irritation is caused by defects in the anatomy of the eyelids, such as extra hair growth or inverting lids. These often require surgical correction of the defect to prevent future damage to the eye.