Understanding and defining MGD
Meibomian gland dysfunction (MGD) is now known to be the leading cause of dry eye disease (DED) in more than 86 percent of patients.1 This knowledge has caused a paradigm shift in our understanding.
Prevalent symptoms may include blurry vision, discomfort, excess tearing, lid irritation, or even burning sensations. There are about 31 meibomian glands within the superior lid and 26 glands in the lower lid.2 These large sebaceous glands were discovered in 1666 by Heinrich Meibom3 (Figure 1) and release meibum, a clear oily substance into the tear film to protect the ocular surface from evaporation of the aqueous layer and to provide stabilization of the tear film by lowering surface tension.4
TFOS establishes standards
Until recently, a global consensus on the definition, classification, diagnosis, or therapy of MGD didn’t exist. The nonprofit Tear Film and Ocular Surface Society (TFOS) tackled this lack of knowledge with its International Workshop on Meibomian Gland Dysfunction.
The objectives of the MGD Workshop were to:
• Conduct an evidence-based evaluation of meibomian gland structure and function in health and disease
• Develop a contemporary understanding of the definition and classification of MGD
• Assess methods of diagnosis, evaluation and grading of severity of MGD
• Develop recommendations for the management and therapy of MGD
• Develop appropriate norms of clinical trial design to evaluate pharmaceutical interventions for the treatment of MGD
• Create a summary of recommendations for future research in MGD