title: Sequential changes of lipid tear film after the instillation of a single drop of a new emulsion eye drop in dry eye patients.
abstract: OBJECTIVE
  The lipid tear film stabilizes the tears by lowering the surface tension and preventing aqueous tear evaporation and may be analyzed by kinetic analysis of the tear interference images. This study investigated changes in the lipid film after application of a new emulsion-based eye drop of Refresh Endura (Allergan, Irvine, CA) in normal subjects and patients with dry eyes.
  
  
  METHODS
  Comparative, nonrandomized interventional study.
  
  
  METHODS
  Five normal subjects and 10 aqueous tear deficiency (ATD) patients with or without lipid tear deficiency were enrolled prospectively.
  
  
  METHODS
  A complete eye examination was performed, including symptom score, tear break-up time, dye staining, and fluorescein clearance test. One eye received a single dose of emulsion eye drop (EED), whereas the other eye received nonpreserved saline as a control. Kinetic analysis of tear interference images taken by DR-1 (Kowa, Japan) was performed before and at various times after instillation of the drops.
  
  
  METHODS
  Symptoms, pattern, thickness, and spread time of the tear film.
  
  
  RESULTS
  Compared with the control, all eyes receiving EED showed rapid restructuring of the preexisting lipid film. In normal persons, restructuring resulted in a thick lipid band across the cornea and a significant increase of the lipid film thickness. For ATD patients, EED application resulted in either a scant, irregular tear film, which became covered by the lipid film, or a modified lipid film changed without forming a band or irregularities. Emulsion eye drops tended to be more comfortable in patients with more severe ATD. Kinetic analysis showed that the mean spread time improved for all patients after EED when compared with baseline or with controls (P<0.05).
  
  
  CONCLUSIONS
  Emulsion eye drop produces significant changes in the tear film of normal and dry eye patients. Further investigation with a prolonged period of treatment is warranted to establish whether EED may help improve the spread and thickness of the lipid tear film in moderate and severe dry eyes.
authors.affiliation: Ocular Surface Center and Ocular Surface Research and Education Foundation, 7000 SW 97th Avenue, Suite 213, Miami, FL 33173, USA.
authors.forename: Mario A
authors.initials: MA
authors.lastname: Di Pascuale
authors.forename: Eiki
authors.initials: E
authors.lastname: Goto
authors.forename: Scheffer C G
authors.initials: SC
authors.lastname: Tseng
mesh_terms: D000328:Adult; D000368:Aged; D003941:Diagnostic Techniques, Ophthalmological; D004338:Drug Combinations; D015352:Dry Eye Syndromes / Q000378:metabolism*; D004655:Emulsions; D005260:Female; D005990:Glycerol / Q000008:administration & dosage; D006801:Humans; D050356:Lipid Metabolism; D008297:Male; D008875:Middle Aged; D009883:Ophthalmic Solutions / Q000008:administration & dosage*; D011136:Polysorbates / Q000008:administration & dosage; D011446:Prospective Studies; D013666:Tears / Q000378:metabolism*
chemical_list: D004338:Drug Combinations; D004655:Emulsions; D009883:Ophthalmic Solutions; D011136:Polysorbates; D005990:Glycerol