Bulletin of Mathematical Biology

, Volume 68, Issue 6, pp 1355–1381

The Effect of the Lipid Layer on Tear Film Behaviour

  • M. B. Jones
  • D. L. S. McElwain
  • G. R. Fulford
  • M. J. Collins
  • A. P. Roberts
Original Article

DOI: 10.1007/s11538-006-9105-9

Cite this article as:
Jones, M.B., McElwain, D.L.S., Fulford, G.R. et al. Bull. Math. Biol. (2006) 68: 1355. doi:10.1007/s11538-006-9105-9

Abstract

This paper investigates the effect of surfactants during tear film deposition and subsequent thinning. The surfactants occur naturally on the surface of the tear film in the form of a lipid layer. A lubrication model is developed that describes lipid spreading and film height evolution. It is shown that lipids may play an important role in drawing the tear film up the cornea during the opening phase of the blink. Further, nonuniform distributions of lipids may lead to a rapid thinning of the tear film behind the advancing lipid front (shock). Experiments using a fluorescein dye technique and using a tearscope were undertaken in order to visualise the motion of the lipid layer and any associated shocks immediately after a blink. It is found that the lipid layer continues to spread upwards on the cornea after the opening phase of the blink, in agreement with the model. Using the experimental data, lipid particles were tracked in order to determine the surface velocity and these results are compared to the model predictions.

Keywords

Tear filmLipid layerThin filmDry eyeMarangoni

Copyright information

© Society for Mathematical Biology 2006

Authors and Affiliations

  • M. B. Jones
    • 1
  • D. L. S. McElwain
    • 1
  • G. R. Fulford
    • 1
  • M. J. Collins
    • 2
  • A. P. Roberts
    • 3
  1. 1.School of Mathematical SciencesQueensland University of TechnologyBrisbaneAustralia
  2. 2.School of OptometryQueensland University of TechnologyBrisbaneAustralia
  3. 3.School of Physical SciencesUniversity of QueenslandBrisbaneAustralia