This co-mingling of aqueous-deficient dry eye and MGD is very important in crafting the approach to treating patients with various degrees of both of these diseases. There have been studies reporting the use of topical cyclosporine in patient groups with MGD combined with aqueous-deficient dry eye, although cyclosporine itself is also not widely available commercially outside of North America.
Further, studies of its efficacy in treatment of MGD or blepharitis have been few outside the United States. Topical azithromycin, a macrolide antibiotic with presumed anti-inflammatory effects, is available in some but not all countries. It should be noted that antibiotic–steroid combinations are used clinically for acute exacerbated cases or for anterior blepharitis, although, because of confusion in clinical differentiation of anterior and posterior blepharitis, use patterns are difficult to assess.
The second most common prescription medication is for a topical antibiotic and/or an antibiotic–steroid combination. Systemic tetracycline is the most common prescription given for the treatment of posterior blepharitis in the United States, 4 but is less frequently used in Europe or Japan. Many forms of lubricants, some with lipid components, are available across the world. Many patients use artificial lubricants, but often because of misdiagnosis and/or concurrent diagnosis of dry eye. As a result, suboptimal and ineffective lid hygiene is commonly practiced and abandoned prematurely as ineffective. Likewise, practitioners on all continents note that patients commonly develop their own methods of performing lid hygiene, regardless of instruction. 2, 3 Practitioners have noted widespread deficiencies in both the patient education provided to differentiate aqueous-deficient dry eye and evaporative dry eye, and perhaps more important, MGD patients' comprehension of these nuances, even when provided, are varied. Recommendations for the performance of lid warming and lid hygiene are commonly made, but the precise technique varies greatly, both in duration and frequency of lid warming and cleansing. Underreporting makes it difficult to assess practice patterns accurately, but most practitioners agree that underdiagnosis is common and clinical follow-up irregular. Overall, treatment of MGD varies greatly among eye care providers on different continents. Consistency in terminology and global adoption of the term “meibomian gland dysfunction” would significantly aid clinical research and clinical care in MGD going forward. Thus, a broad scope of documents was reviewed in this process. It should be noted that, in many of the clinical textbooks and previous reports, terminology is often interchanged and the management of anterior and posterior blepharitis and/or meibomitis is often considered concurrently. To achieve these goals, a comprehensive review of clinical textbooks and the scientific literature was performed and the quality of published evidence graded according to an agreed on standard, using objective criteria for clinical and basic research studies adapted from the American Academy of Ophthalmology Practice Guidelines 1 ( Table 1).
The goals of the subcommittee were to review the current practice and published evidence of medical and surgical treatment options for meibomian gland dysfunction (MGD) and to identify areas with conflicting, or lack of, evidence, observations, concepts, or even mechanisms where further research is required.