What structural change can chronic blepharitis cause if left untreated?

Chronic blepharitis, if left untreated, can lead to madarosis, which is the loss of eyelashes. Blepharitis is an inflammatory condition affecting the eyelids, often resulting in symptoms such as redness, irritation, and crusting. Over time, chronic inflammation can damage the hair follicles along the eyelid margins, leading to a reduction in eyelash growth. Madarosis is significant as eyelashes play an important role in protecting the eyes from environmental factors and debris, and their absence can increase the risk of complications, including exposure problems and irritation to the ocular surface.

The other conditions mentioned, such as hypertelorism (a facial structural anomaly), distichiasis (the presence of an extra row of eyelashes), and tristichiasis (misplaced eyelashes), are not typically associated with the chronic inflammation and changes induced by untreated blepharitis. Hence, they do not relate directly to the consequences of prolonged blepharitis. In contrast, madarosis is a direct result of the damage incurred to the eyelid structures and the hair follicles therein due to ongoing inflammation.