Imaging of meibomian glands: from bench to bedside and back

Objective Imaging Diagnostics for Dry Eye Disease

“…OCT meibography showed a decreased MG length and width in obstructive MGD, which correlated with ocular surface symptoms and signs [47]. However, so far, there are only preliminary data; thus, further studies are needed for clinical application of MG imaging using OCT [48].…”

“…However, IVCM has a limitation that it is not capable of cellular and tissue phenotyping, and analysis is only based on morphology and reflectivity [ 48 ]. The small field of view (<0.25 mm [ 2 ]) is also a major limitation of the device [ 48 ].…”

Imaging Biomarkers for Dry Eye Disease

“…26 Validated objective assessment of MGs would be essential for DED patients' subclassification and stratification and to monitor the response to some treatments. 27 Moreover, in vivo imaging studies have demonstrated MG changes associated with aging 28,29 and contributed to a better understanding of inflammatory/ hyposecretive DED 30,31 and other ocular surface diseases. 32,33 Technological evolution provided us several noninvasive (or nearly noninvasive) tools, 34 including infrared (IR) meibography, 35 in vivo confocal microscopy (IVCM), 36 and OCT meibography.…”

“…37 In vivo confocal microscopy not only has a great potential allowing for in vivo study of the ocular surface tissues at a cellular level but also has major limitations mainly due to the small field of view and to the lack of validated and user-friendly software for image analysis. 27 Moreover, IVCM analysis is purely morphologic, without any tissue and cellular phenotyping, and recently published data seriously challenge the interpretation of confocal images of MGs acinar units. 38 Optical coherence tomography meibography, performed by a long coherence swept laser source, might provide interesting and novel tridimensional information, but at present, we have only preliminary data obtained with customized systems, and there is need to standardize this approach and to obtain validated biomarkers by this technology.…”

“…However, working on the validation of potential IR meibography-based biomarkers, we have to consider that, at present, this approach has some important limits, including the poor diagnostic accuracy for MGD (when it is taken alone, without functional data), 45 the relatively low resolution, and the still subjective interpretation of the "dark drop-out areas." 27…”