- Meibum Collection: Meibomian glands at the eyelid margin secrete Meibum, that forms an important component of tear film that helps in preventing excessive evaporation of outer layer and maintains the stability of tears on the eye. Meibum will be collected using a sterile, single-use, golf spud by gently squeezing the eyelids against the eye, slightly everted outwards. Very minimal amount of meibum is expressed during this procedure and will not alter any of the normal functions of the tears. This meibum will then be stored for further analysis. Meibum and tear samples collected from the subjects will be stored in a -80º C freezer in the microbiology laboratory, Room No. 2.028, School of Optometry and Vision Science, UNSW.