title: [Tear function index validation for dry eye diagnosis].
abstract: OBJECTIVE
  To develop a simple method for the clinical evaluation of tear dynamics and evaluate its usefulness in the diagnosis of dry eye syndrome.
  
  
  METHODS
  The study includes 170 eyes from 85 adults. 102 eyes had a Schirmer's test value of less than 10 mm and subjective symptoms of dry eye. Tear function index (TFI) was calculated in all the cases using prepared drops with 0.5% fluorescein and 0.4% oxibuprocaína. Five minutes later a Schirmer strip was placed on the conjunctival fornix. Schirmer's test and tear clearance were calculated after a further five minutes. Tear clearance was measured using a table of fluorescein concentrations. TFI is the quotient between the value of the Schirmer's test and TCR.
  
  
  RESULTS
  The cut-off value of TFI in dry eye is 74. At this point the sensitivity of this method is 74% and the specificity is 63%. The Schirmer's test results did not correlate with the tear clearance results.
  
  
  CONCLUSIONS
  TFI is a rapid and sensitive method of identification of subjects with dry eye. The lack of correlation between TFI and TCR is because these methods evaluate different aspects of tear dynamics.
authors.affiliation: Unidad de Superficie e Inflamación Ocular, Hospital Clínico Universitario de San Carlos, Madrid. EBUSQUI@terra.es
authors.forename: E
authors.initials: E
authors.lastname: Vico
authors.forename: J M
authors.initials: JM
authors.lastname: Benítez del Castillo
authors.forename: R A
authors.initials: RA
authors.lastname: Giménez
authors.forename: C
authors.initials: C
authors.lastname: Fernández
authors.forename: J
authors.initials: J
authors.lastname: García Sánchez
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D003430:Cross-Sectional Studies; D015352:Dry Eye Syndromes / Q000175:diagnosis* / Q000503:physiopathology; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D013666:Tears