Changes in Lower Lid Meibomian Glands May Lead to Contact Lens Discomfort

Alterations to meibomian gland morphology can influence contact lens discomfort and increase the severity of symptoms, according to a study published in Contact Lens and Anterior Eye. The investigation shows this is the case even when the glandular changes are not clinically apparent via meibum quality and expressibility.

Researchers enrolled 60 participants (38 women, 22 men; mean age 23.8±6.3 years) into a prospective, observational, case control study and divided them into 3 groups: symptomatic contact lens wearers (n=19), asymptomatic contact lens wearers (n=19), and individuals who do not wear contact lenses (n=22). Participants with symptoms of contact lens discomfort had a Contact Lens Dry Eye Questionnaire-8 (CLDEQ-8) score of at least 12.

Participants had their symptoms assessed by completing the Ocular Surface Disease Index (OSDI) questionnaire. Testing included tear break-up time (TBUT) and corneal staining, quality and expressiblity of meibum secretion, and meibography.

Researchers also evaluated the number of meibomian glands, the number of partial meibomian glands, percentage of meibomian gland loss, and percentage of tortuosity. 

In both contact lens wearer groups, the study shows a significant positive correlation between the CLDEQ-8 scores and the number of meibomian glands in the upper eyelid (rho=0.47, P =.003). However, this result disappeared when symptomatic contact lens wearers were analyzed separately, researchers explain. This indicates that the finding may be the result of chance, the study authors report. 

In symptomatic wearers, the study shows a significant correlation between the questionnaire scores and the number of partial glands (rho=0.49, P =.034), the percentage of partial glands (rho=0.61, P =.005), and gland loss in the lower lid.

The relationship between gland morphology and contact lens discomfort was different between upper and lower eyelids, with the lower lid morphology being the best predictor of the degree of symptoms.

“[Meibomian gland] alteration of the lower and upper eyelids may be different and while it is important to monitor both eyelids, in [contact lens] wearers the lower eyelid may be particularly useful in showing changes that lead to the onset of symptoms,” according to researchers.

However, the investigators report that none of the differences between the groups were significant in gland morphology of the upper or lower eyelids, gland loss, or the number of partial glands or tortuosity of the upper or lower eyelids. The study results suggest that contact lens wear itself does not affect meibomian gland morphology.

Study limitations include cross-sectional design, lower mean age of participants, and short duration of study.