Which technique highlights meibomian gland dropout in humans and dogs?

• A. Interferometry
• B. Noncontact infrared meibography
• C. Fluorescein staining
• D. Ultrasonography

Answer: (B)

Noncontact infrared meibography directly visualizes the meibomian glands within the eyelids and reveals dropout as areas where gland tissue is absent or atrophic. Using infrared light through the eyelid, it produces high-contrast images of the glands without contact, making it safe and repeatable for both humans and dogs. Areas of dropout appear as gaps where glands should be, providing a clear assessment of gland health and function.

Interferometry measures tear film lipid layer thickness rather than gland morphology; fluorescein staining highlights surface epithelial damage, not gland structure; ultrasonography can image orbital and some eyelid tissues but lacks the resolution and standard use for detailing meibomian gland dropout.