What describes trichiasis?

Trichiasis is specifically characterized by ingrown eyelashes that turn inward and come into contact with the cornea, leading to irritation and potential damage to the eye. This condition occurs when the eyelashes grow in a direction that is abnormal, irritating the sensitive tissues of the eye surface. This can cause discomfort, redness, and even vision problems if not treated.

In contrast, the other choices do not accurately describe trichiasis. Excess eyelashes refer to an increased quantity of lashes, which is not indicative of the inward growth characteristic of trichiasis. An infection of the eyelashes would imply some form of inflammation or condition affecting the lashes rather than the direction of growth, while loss of eyelashes relates to alopecia or other conditions that lead to absence rather than misalignment. Thus, the focus on the ingrowth and resulting irritation is what defines trichiasis.