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Bead Based Multiplex Assay for Analysis of Tear Cytokine Profiles
Published on: October 13, 2017
[Tear function index validation for dry eye diagnosis]
E Vico1, J M Benítez del Castillo, R A Giménez
1Unidad de Superficie e Inflamación Ocular, Hospital Clínico Universitario de San Carlos, Madrid. EBUSQUI@terra.es
Purpose:
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.
Conclusion:
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.
