Damage to the meibomian glands would most likely result in which tear film change?

• A. Increased tear production
• B. More stable tear film due to lipid layer integrity
• C. Increased evaporation from lipid layer deficiency
• D. No effect on tear film

Answer: (C)

The outer lipid layer of the tear film, produced by the meibomian glands, serves to slow evaporation and stabilize the tear film. When these glands are damaged, lipid secretion drops, thinning or disrupting the lipid layer. Without that protective lipid coating, the aqueous portion of the tear film evaporates more quickly, making the tear film less stable and prone to rapid breakup. This is why the most likely tear film change is increased evaporation due to lipid layer deficiency. Increased tear production would not be expected from lipid loss, a stable tear film would require an intact lipid layer, and there would indeed be an effect on the tear film rather than none.