Lipiview interferometer

Lipid layer thickness (LLT) and blinking pattern within 20 s were evaluated using LipiView interferometer (Johnson & Johnson, New Brunswick, New Jersey), and all participants were told to blink normally during whole examinations. To get a reliable LLT, the same examination was performed again after participants rested for 10 min. The average of LLT was used for analysis in this study. Then, two corneal specialists (P.-Y. Lin and N.-W. Fan) assessed tear film break-up time (TBUT), Schirmer’s test without anesthetic, absence or presence of lid telangiectasia, absence or presence of anterior displacement of mucocutaneous junction over lateral third, middle, and medial third of lower eyelids and each area was scored 0 for absence and 1 point for presence. The meibum expressibility over whole lower eyelids in response to moderate digital pressure was evaluated and the total number of expressible glands was counted. Meibum quality was scored as follows: 0 = clear liquid, 1 = cloudy fluid, 2 = cloudy with particulate fluid, 3 = toothpaste-like meibum, and 4 = total atrophic meibum. Meiboscore was determined by the loss of meibomian gland detected by transillumination through everted eyelids, scored from grade 0 through grade 3 (0 = no loss of meibomian gland, 1 = less than 25% loss, 2 = 25–50% loss, 3 = 50–75% loss, 4 = more than 75% loss) [17 (link)].

Assessments of the anterior segment of both eyes were performed according to standardized protocols by a team of seven ophthalmologists with expertise in DE and MGD (LIME members). TMH was measured with the Keratograph 5 M instrument (Oculus, Wetzlar, Germany); the thickness of the lipid layer of the tear film was determined with the LipiView interferometer (Johnson and Johnson, Stamford, CT, USA); lipid layer grade and noninvasive breakup time of the tear film were assessed with the DR-1α interferometer (Kowa, Aichi, Japan) [17 (link)]; lid margin abnormalities [18 (link)]—including plugging (scale of 0–3), vascularity (0–3), displacement of the mucocutaneous junction (0–3), and irregularity (0–3)—as well as fluorescein-based breakup time of the tear film, corneal–conjunctival fluorescein staining score (0–9) [19 (link)], the absence or presence of conjunctivochalasis, pterygium, conjunctival papillae, and Demodex mites, and the grading of meibum expressed with digital pressure (0–3) [20 (link)] were evaluated by slitlamp microscopy; the meiboscore (0–3 for each eyelid), which reflects the morphology of meibomian glands, was determined with a noncontact meibography system (Topcon, Tokyo, Japan) [21 (link)]; and the volume of tear fluid was measured by Schirmer’s test without the administration of anesthetic.