What term describes hairs that grow from normal skin and contact the cornea or conjunctiva?

The term that describes hairs growing from normal skin that come into contact with the cornea or conjunctiva is "trichiasis." This condition occurs when the eyelashes or adjacent hairs are misdirected and rub against the surface of the eye, leading to irritation, inflammation, and potential damage to the ocular tissues. The misdirection does not originate from an anatomical abnormality of the eyelids but rather involves normal hair follicles situated in the vicinity of the eye.

Understanding trichiasis is crucial in veterinary ophthalmology, as it can lead to serious ocular issues, including corneal ulcers and other complications if not addressed. Treatment often involves removing the offending hairs or addressing the underlying causes to prevent hair from irritating the eyes.

In contrast, ptosis refers to the drooping of the eyelid, tarsorrhaphy is a surgical procedure to close the eyelids partially or completely, and entropion is a condition where the eyelid rolls inward, causing the lashes to rub against the eyeball. Each of these terms relates to different anatomical or surgical conditions affecting the eyelids but does not address the presence of hairs from normal skin directly contacting the ocular surface.