Meibomian gland dysfunction central to workshop consensus

Boston-The recently published report from the International Workshop on Meibomian Gland Dysfunction ("MGD Workshop") provides an evidence-based review of current knowledge about meibomian gland structure and function in health and disease, offers an idea bank for researchers with an interest in the field, and provides practical guidance to clinicians on the evaluation and management of a very common disorder, which is considered the leading cause of evaporative dry eye disease.

In addition, the MGD Workshop participants and leadership from the project's sponsor, the non-profit Tear Film & Ocular Surface Society (TFOS), hope the report will stimulate increased recognition of MGD and future studies, ultimately leading to better patient care.

The project began in November 2008 and benefited from the contributions of more than 50 leading experts in a process that involved extensive, in-depth literature review, discussion, and consensus development. In undertaking the MGD Workshop, the organizers aimed to address the absence of any global consensus on the definition, classification, diagnosis, and management of a disorder that carries a high burden because of its prevalence and impact on quality of life, and they hoped their work would stimulate future research, explained Kelly K. Nichols, OD, MPH, PhD, chairwoman of the MGD Workshop Steering Committee and associate professor, Ohio State University College of Optometry, Columbus.

"There has been some confusion in the past because MGD has been considered a form of blepharitis," said Gary N. Foulks, MD, vice chairman of the MGD Workshop Steering Committee and recently retired from his position as Arthur & Virginia Keeney Professor of Ophthalmology, Department of Ophthalmology and Visual Sciences, University of Louisville School of Medicine, Louisville, KY. "However, the pathophysiology and behavior of inflammation of the anterior portion of the eyelid is very different [from] the posterior portion of the eyelid where the meibomian glands reside.

"This report helps to clarify the causes and management of the posterior eyelid disease and its effects on the tear film and the ocular surface," he added.

The entire TFOS MGD Report is the subject for a special issue of Investigative Ophthalmology & Visual Science (2011;52), the official journal of the Association for Research in Vision and Ophthalmology, and it can be accessed and downloaded through the TFOS Web site ( http://www.tearfilm.org).

The publication comprises an introduction by Dr. Nichols, the executive summary, and reports from the MGD Workshop's seven subcommittees: 1) definition and classification, 2) anatomy, physiology and pathophysiology, 3) tear film lipids and lipid-protein interactions 4) epidemiology and risk factors, 5) diagnosis, 6) management and treatment, and 7) clinical trials.

In addition to explaining the impetus for the project, its objectives, and the process used to create the report, the introduction highlights a number of controversies that emerged within the various subcommittees. The process of literature review and consensus development identified both areas where knowledge is suboptimal and issues requiring further investigation.

"The MGD Workshop participants were often surprised to find out how little is known in some respects about the meibomian gland and MGD," Dr. Nichols said. "For example, there has never been a natural history study of the disorder, there are gaps in our understanding of the composition of the meibomian gland secretions and how they are modified by disease and therapeutic interventions, and there is no single good diagnostic test for MGD.

"I believe the information included in the introduction offers a blueprint for all researchers with an interest in the meibomian gland and provides guidance for clinical and basic science research studies, all of which may be considered translational considering their potential to change patient care eventually," Dr. Nichols added.