What describes the condition where eyelid margins roll in, causing hairs to touch the ocular surface?

The condition described is entropion, which involves the inward rolling of the eyelid margins. In this situation, the eyelashes and adjacent hair can come into contact with the surface of the eye, leading to irritation, discomfort, and potential damage to the cornea. This can result in symptoms such as redness, tearing, and increased sensitivity to light.

Entropion is often seen in certain breeds of dogs and can be a congenital issue, meaning it is present at birth, or may develop later in life due to factors such as aging or scarring. Understanding entropion is crucial for veterinary ophthalmologists because timely diagnosis and treatment can alleviate discomfort for the animal and prevent serious complications associated with chronic ocular irritation.

Other conditions like ectropion involve the eyelid rolling outward, which does not touch the ocular surface, while blepharitis refers to inflammation of the eyelid margins, and lagophthalmos describes an inability to close the eyes completely, often leading to dryness rather than hair-to-eye contact. These distinctions emphasize the unique clinical relevance of entropion in managing ocular health in animals.