title: The association between subjective and objective parameters for the assessment of dry-eye syndrome.
abstract: OBJECTIVE
  The aim of the present study was to evaluate the association between symptoms and different clinical signs in patients with dry-eye syndrome (DES).
  
  
  METHODS
  Fifty-two patients with DES were included in the present cross-sectional study. For assessment of symptoms, the Ocular Surface Disease Index (OSDI) was used. Clinical parameters included measurement of tear break up time (BUT), corneal fluorescein staining, tear osmolarity, and ocular scattering index (OSI). Tear film thickness (TFT) was assessed using a custom-built optical coherence tomography (OCT) system with an axial resolution of 1.2 μm. In addition, impression cytology was performed. Correlation coefficients were calculated using linear regression analysis.
  
  
  RESULTS
  The mean OSDI in the present study population was 28.9 ± 17.6, the mean TFT was 4.1 ± 1.3 μm. A significant negative correlation was found between OSDI and TFT (r = -0.34, P = 0.01). Tear film thickness correlated positively with BUT (r = 0.35, P = 0.01), but with no other signs of DES. No association was found between OSDI and the other evaluated signs.
  
  
  CONCLUSIONS
  The study population mainly comprised of patients with mild to moderate DES. Tear film thickness as measured with a custom-built OCT device correlated with subjective symptoms in these patients. In agreement with previous data, the association between other signs and symptoms was weak in the present study. Measurement of TFT with OCT may become a valuable tool in the management of DES patients. (ClinicalTrials.gov number, NCT01753687.)
authors: Department of Clinical Pharmacology, Medical University of Vienna, Austria Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Austria.
authors: Doreen
authors: D
authors: Schmidl
authors: Department of Clinical Pharmacology, Medical University of Vienna, Austria.
authors: Katarzyna Jadwiga
authors: KJ
authors: Witkowska
authors: Department of Ophthalmology, Paracelsus Medical University, Salzburg, Austria.
authors: Semira
authors: S
authors: Kaya
authors: Department of Clinical Pharmacology, Medical University of Vienna, Austria.
authors: Carina
authors: C
authors: Baar
authors: Department of Clinical Pharmacology, Medical University of Vienna, Austria.
authors: Henrik
authors: H
authors: Faatz
authors: Department of Ophthalmology and Optometry, Medical University of Vienna, Austria.
authors: Johannes
authors: J
authors: Nepp
authors: Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Austria.
authors: Angelika
authors: A
authors: Unterhuber
authors: Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Austria.
authors: René Marcel
authors: RM
authors: Werkmeister
authors: Department of Clinical Pharmacology, Medical University of Vienna, Austria.
authors: Gerhard
authors: G
authors: Garhofer
authors: Department of Clinical Pharmacology, Medical University of Vienna, Austria Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Austria.
authors: Leopold
authors: L
authors: Schmetterer
mesh_terms: D000328:Adult; D003430:Cross-Sectional Studies; D015352:Dry Eye Syndromes / Q000175:diagnosis* / Q000503:physiopathology; D005260:Female; D006801:Humans; D007090:Image Interpretation, Computer-Assisted; D008297:Male; D008875:Middle Aged; D012016:Reference Values; D013666:Tears / Q000502:physiology; D041623:Tomography, Optical Coherence; D014792:Visual Acuity / Q000502:physiology
keywords: corneal fluorescein staining; dry-eye syndrome; impression cytology; objective scattering index; ocular surface disease index; optical coherence tomography; tear break up time; tear film thickness; tear osmolarity