What clinical sign may indicate involutional entropion?

The clinical sign that indicates involutional entropion is the horizontal laxity of the medial and/or lateral canthal tendons. Involutional entropion is a condition typically associated with aging, where the eyelid margins turn inward due to changes and laxity in the surrounding structures, including the canthal tendons.

As the tendons become lax, they can no longer provide adequate support to keep the eyelids in their proper position. This laxity leads to the inward turning of the eyelid, causing irritation and potentially resulting in serious complications such as corneal abrasion.

The other listed choices do not directly indicate involutional entropion. Cicatrization of the eyelid may occur due to scarring from previous injuries or infections but is not characteristic of the involutional type. Excessive tear film production may result from various conditions such as dry eye syndrome, and redness of the conjunctiva could be a sign of many ocular conditions, including inflammation but does not specifically suggest involutional entropion. Therefore, the correct recognition of horizontal laxity in the canthal tendons is key to identifying this condition.