A recent study identified a new screening tool for detecting obstructive meibomian gland dysfunction (MGD): lipid layer thickness (LLT). In the study, researchers divided 209 eyes of 209 patients diagnosed with obstructive MGD into three groups based on age: a young group (ages 20 to 39), a middle-aged group (ages 40 to 59) and an older group (ages 60+).
All patients filled out the Ocular Surface Disease Index questionnaire and underwent examinations for LLT, tear meniscus height, noninvasive and invasive tear break-up time, corneal fluorescein staining, eyelid margin abnormalities, Schirmer I test and meibomian gland function and morphology.
Of the 209 eyes, the median LLT was 57nm, but from group to group, this value differed significantly (Table 1). Additionally, the researchers noted that LLT was positively correlated with age, and that there was a negative correlation between LLT and meibomian gland dropout in all groups. LLT was positively correlated with gland expressibility in all groups, but not statistically significant in the young group.
The researchers concluded that LLT increases with age and is significantly correlated with both meibomian gland secretion and morphology in middle-aged and older patients with obstructive MGD. They suggest using LLT as a screening tool for detecting obstructive MGD, as well as taking age into account when interpreting LLT values.
Table 1. Median Lipid Layer Thickness
|MGD Groups (n=209)||Median LLT|
|Young (ages 20 to 39)||51nm|
|Middle-aged (ages 40 to 59)||59.5nm|
|Older (ages 60+)||62nm|
Li J, Ma J, Hu M, et al. Assesment of tear film lipid layer thickness in patients with meibomian gland dysfunction at different ages. BMC Ophthalmol. October 6, 2020. [Epub ahead of print].