The lipid layer: The outer surface of the ocular surface tear film

James P McCulley, Ward E. Shine

Research output: Contribution to journalShort surveypeer-review

73 Scopus citations


The outer layer of the tear film - the lipid layer - has numerous functions. It is a composite monolayer composed of a polar phase with surfactant properties and a nonpolar phase. In order to achieve an effective lipid layer, the nonpolar phase, which retards water vapor transmission, is dependent on a properly structured polar phase. Additionally, this composite lipid layer must maintain its integrity during a blink. The phases of the lipid layer depend on both lipid type as well as fatty acid and alcohol composition for functionality. Surprisingly, the importance of the composition of the aqueous layer of the tear film in proper structuring of the lipid layer has not been recognized. Finally, lipid layer abnormalities and their relationship to ocular disease are beginning to be clarified.

Original languageEnglish (US)
Pages (from-to)407-418
Number of pages12
JournalBioscience reports
Issue number4
StatePublished - 2001


  • Disease
  • Lipid
  • Ocular
  • Polar
  • Surfactant
  • Tear film

ASJC Scopus subject areas

  • Biophysics
  • Biochemistry
  • Molecular Biology
  • Cell Biology


Dive into the research topics of 'The lipid layer: The outer surface of the ocular surface tear film'. Together they form a unique fingerprint.

Cite this