Meibomian gland imaging: A review

Abstract

The meibomian glands of the upper and lower eyelids play a valuable role in secreting the lipidlayer of the tear film. Disturbances in meibomian gland function may result in altered secretion andvariations in tear composition which may lead to meibomian gland dysfunction and evaporativedry eye, leading to ocular discomfort. To diagnose and monitor the structural and functionalchanges occurring within the glands of the eyelids, various imaging techniques are available.Some of the methods used to evaluate the tears and therefore the meibum within the tears includeevaporimetry, interferometry, tear osmolarity and meibometry. With these techniques, changesin the lipid layer of the tear film can be quantified and alterations in meibomian gland functionassessed. Meibography is an additional method that can be used; it has the unique feature ofallowing the assessment of meibomian gland morphology during ocular surface disease processes.The aim of this review is to create an improved understanding of the meibomian glands and theways that they may be investigated in order to expand on the treatment methods available.