title: Ocular surface assessment in soft contact lens wearers; the contribution of tear osmolarity among other tests.
abstract: OBJECTIVE
  To determine whether tear osmolarity contributes to the assessment of the ocular surface in soft contact lens (CL) wearers.
  
  
  METHODS
  Prospective, case-control series in 44 CL wearers (28 tolerant and 16 intolerant) and 34 healthy subjects. Every patient underwent a thorough ophthalmic examination with a tear osmolarity test (TearLab System), conjunctival impression cytology and meibomian lipid sampling. Symptoms, break-up time (BUT), tear osmolarity, conjunctival expression of HLA-DR and meibomian fatty acid composition were evaluated.
  
  
  RESULTS
  Tear osmolarity did not differ between controls and CL wearers (p= 0.23). Flow cytometry results expressed in antibody-binding capacity (ABC) units and percentage of positive cells revealed a significant difference between the intolerant CL wearer group and the control group (p< 0.0001). Comparisons between tolerant and intolerant CL wearers showed only a significant difference for mean fluorescence levels expressed in ABC units (p< 0.0001). The BUT was significantly shorter in intolerant and tolerant CL wearers subjects than in healthy subjects (p< 0.0001), whereas there was no significant difference in meibomian fatty acid composition (p= 0.99) between the two groups.
  
  
  CONCLUSIONS
  Contact lens wear is responsible for ocular surface alterations whose patterns are very similar to those reported in early dry-eye syndrome. However, tear osmolarity was not modified in these selected CL wearers. The yield of tear osmolarity with TearLab™ in assessing ocular surface disorders in CL wearers deserves further investigation.
authors.affiliation: Department of Ophthalmology University Hospital, Dijon, FranceLaboratory of Toxicology, Faculty of Pharmaceutical and Biological Sciences, University of Paris-5 René Descartes, Paris, FranceEye and Nutrition Research Group, Centre des Sciences du Goût et de l'Alimentation, UMR 1324 INRA, 6265 CNRS, University of Burgundy, Dijon, France.
authors.forename: Aurore
authors.initials: A
authors.lastname: Muselier-Mathieu
authors.forename: Alain M
authors.initials: AM
authors.lastname: Bron
authors.forename: Bénigne
authors.initials: B
authors.lastname: Mathieu
authors.forename: Maxime
authors.initials: M
authors.lastname: Souchier
authors.forename: Françoise
authors.initials: F
authors.lastname: Brignole-Baudouin
authors.forename: Niyazi
authors.initials: N
authors.lastname: Acar
authors.forename: Lionel
authors.initials: L
authors.lastname: Brétillon
authors.forename: Catherine
authors.initials: C
authors.lastname: Creuzot-Garcher
mesh_terms: D000328:Adult; D016022:Case-Control Studies; D003228:Conjunctiva / Q000378:metabolism / Q000473:pathology*; D003263:Contact Lenses, Hydrophilic / Q000009:adverse effects*; D015352:Dry Eye Syndromes / Q000209:etiology* / Q000378:metabolism; D005227:Fatty Acids / Q000378:metabolism; D005260:Female; D005434:Flow Cytometry; D006684:HLA-DR Antigens / Q000378:metabolism; D006801:Humans; D008297:Male; D008537:Meibomian Glands / Q000378:metabolism; D009994:Osmolar Concentration; D011446:Prospective Studies; D011795:Surveys and Questionnaires; D013666:Tears / Q000737:chemistry*; D055815:Young Adult
chemical_list: D005227:Fatty Acids; D006684:HLA-DR Antigens
keywords: contact lens; dry eye; fatty acid; inflammation; tear osmolarity