title: Tear film thickness after treatment with artificial tears in patients with moderate dry eye disease.
abstract: OBJECTIVE
  This study was designed to investigate the effect of a single-drop instillation of different lacrimal substitutes on tear film thickness (TFT) assessed with optical coherence tomography in patients with mild to moderate dry eye disease.
  
  
  METHODS
  The study was performed in a randomized, double-masked, controlled parallel group design. Patients received a single dose of either unpreserved trehalose 30 mg/mL and sodium hyaluronate 1.5 mg/mL (TH-SH, Thealoz Duo), unpreserved sodium hyaluronate, 0.15% (HA, Hyabak) or sodium chloride, 0.9% (NaCl, Hydrabak) eye drops. Sixty patients finished the study according to the protocol. TFT was measured with a custom-built ultrahigh-resolution Fourier domain optical coherence tomography system providing a resolution of 1.2 μm.
  
  
  RESULTS
  The mean TFT before treatment was 2.5 ± 0.4 μm. Ten minutes after instillation, TFT significantly increased in the TH-SH group from 2.4 ± 0.4 to 3.1 ± 0.9 μm (P < 0.01) and in the HA group from 2.4 ± 0.3 to 2.9 ± 0.5 μm (P < 0.01), whereas no significant change was observed in the NaCl group (from 2.6 ± 0.4 to 2.7 ± 0.4 μm, P = 0.76). The increase in TFT remained statistically significant up to 240 minutes after administration of TH-SH. In contrast, the increase in TFT after administration of HA was only statistically significant at 10, 20, and 40 minutes after drop instillation.
  
  
  CONCLUSIONS
  The findings of this study indicate that single instillation of TH-SH and HA eye drops increases TFT in patients with dry eye disease. The data also indicate longer corneal residence of the TH-containing eye drops. The effect of multiple instillation and long-term use of artificial tears on TFT warrants further investigation.
authors: *Department of Clinical Pharmacology, Medical University Vienna, Vienna, Austria; †Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna, Austria; ‡Department of Ophthalmology, Paracelsus University Salzburg, Salzburg, Austria; and §Department of Ophthalmology, Medical University of Vienna, Vienna, Austria.
authors: Doreen
authors: D
authors: Schmidl
authors: Leopold
authors: L
authors: Schmetterer
authors: Katarzyna J
authors: KJ
authors: Witkowska
authors: Angelika
authors: A
authors: Unterhuber
authors: Valentin Aranha
authors: VA
authors: dos Santos
authors: Semira
authors: S
authors: Kaya
authors: Johannes
authors: J
authors: Nepp
authors: Carina
authors: C
authors: Baar
authors: Peter
authors: P
authors: Rosner
authors: René M
authors: RM
authors: Werkmeister
authors: Gerhard
authors: G
authors: Garhofer
mesh_terms: D000287:Administration, Topical; D000328:Adult; D004311:Double-Blind Method; D004338:Drug Combinations; D015352:Dry Eye Syndromes / Q000188:drug therapy* / Q000378:metabolism; D005260:Female; D005583:Fourier Analysis; D006801:Humans; D006820:Hyaluronic Acid / Q000008:administration & dosage*; D065346:Lubricant Eye Drops / Q000008:administration & dosage; D008297:Male; D008875:Middle Aged; D011795:Surveys and Questionnaires; D013666:Tears / Q000737:chemistry*; D041623:Tomography, Optical Coherence; D014199:Trehalose / Q000008:administration & dosage*; D055675:Viscosupplements
chemical_list: D004338:Drug Combinations; D065346:Lubricant Eye Drops; D055675:Viscosupplements; D006820:Hyaluronic Acid; D014199:Trehalose