title: Differentiation of lipid tear deficiency dry eye by kinetic analysis of tear interference images.
abstract: OBJECTIVE
  To use kinetic changes to characterize tear interference images in patients with lipid tear deficiency (LTD) dry eye.
  
  
  METHODS
  We used a DR-1 camera to digitize and analyze sequential images of tear interference on the central 8 mm of the cornea at the start of complete blinking in 11 healthy volunteers and 8 patients with LTD and noninflamed meibomian gland dysfunction.
  
  
  METHODS
  We studied tear lipid spread time and pattern, stability of the lipid after spread, and distribution of thickness in a prospective, case-control study.
  
  
  RESULTS
  On complete lid closure, the lipid spread was horizontal in healthy eyes but vertical in LTD (P<.001). Mean +/- SD lipid spread time was 0.36 +/- 0.22 seconds in healthy eyes but 3.54 +/- 1.86 seconds in LTD (P<.001). Conventional DR-1 grading could not distinguish these groups (P =.32). Mean +/- SD lipid film thickness in healthy eyes was 74.5 +/- 6.9 nm, thicker than the 43.8 +/- 10.6 nm in LTD (P<.001), and this result was confirmed by qualification with intensity histogram (P<.001).
  
  
  CONCLUSIONS
  Kinetic analysis of the tear interference revealed distinctive differences in the time and pattern of lipid spread and the distribution and stability of resultant lipid thickness between healthy subjects and patients with LTD. This method can be coupled with others for formulating effective therapies for patients with dry eye.
authors.affiliation: Ocular Surface Center, Ocular Surface Research and Education Foundation, 8780 SW 92nd St, Suite 203, Miami, FL 33176, USA.
authors.forename: Eiki
authors.initials: E
authors.lastname: Goto
authors.forename: Scheffer C G
authors.initials: SC
authors.lastname: Tseng
mesh_terms: D000328:Adult; D001767:Blinking; D016022:Case-Control Studies; D003941:Diagnostic Techniques, Ophthalmological; D015352:Dry Eye Syndromes / Q000175:diagnosis / Q000378:metabolism*; D005141:Eyelid Diseases / Q000175:diagnosis / Q000378:metabolism*; D005260:Female; D006801:Humans; D007700:Kinetics; D008055:Lipids / Q000172:deficiency*; D008297:Male; D008537:Meibomian Glands / Q000378:metabolism* / Q000473:pathology; D008875:Middle Aged; D010781:Photography / Q000379:methods; D011446:Prospective Studies; D013666:Tears / Q000378:metabolism*; D017155:Wettability
chemical_list: D008055:Lipids