title: Effect of artificial tears on visual acuity.
abstract: OBJECTIVE
  To study the effect of commonly used preservative free artificial tear, carboxymethylcellulose (CMC) 0.5% (Refresh Plus, Allergan, Irvine, California) on visual acuity in symptomatic dry eye (SDE) and asymptomatic dry eye (ADE) patients.
  
  
  METHODS
  Nonrandomized prospective clinical trial.
  
  
  METHODS
  Prospective study involving 20 patients (40 eyes) with SDE and 20 patients (40 eyes) with ADE, all 40 years and older, were recruited from a clinic setting over a 1-month period. Distance visual acuity was measured by the Early Treatment of Diabetic Retinopathy Study (ETDRS) vision chart and near visual acuity was measured by the Lighthouse Near Vision chart before and 30 seconds after instillation of one drop of CMC. Distance and near visual acuity was measured both with and without correction. The duration of action of CMC was measured at 1-minute intervals until the patient's visual acuity returned to pretear level.
  
  
  RESULTS
  In both SDE and ADE groups, uncorrected and corrected near and distance vision showed a statistically significant improvement after the use of CMC (P < .05). There was no statistically significant difference in improvement between the SDE and ADE groups in all categories (P values > .05). The mean duration of improvement of vision was 2.93 minutes in the SDE group and 3.70 minutes in the ADE group (P = .036).
  
  
  CONCLUSIONS
  CMC 0.5% provides a temporary yet significant improvement in the visual acuity of SDE and ADE patients. The effect of artificial tears on visual acuity may be of diagnostic value in detecting ocular surface abnormality in symptomatic and asymptomatic patients.
authors.affiliation: Laser and Corneal Surgery Associates, PC, New York 10022, USA.
authors.forename: Mohammad-Reza
authors.initials: MR
authors.lastname: Nilforoushan
authors.forename: Robert A
authors.initials: RA
authors.lastname: Latkany
authors.forename: Mark G
authors.initials: MG
authors.lastname: Speaker
mesh_terms: D000368:Aged; D002266:Carboxymethylcellulose Sodium / Q000008:administration & dosage / Q000494:pharmacology*; D015352:Dry Eye Syndromes / Q000188:drug therapy* / Q000503:physiopathology; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009883:Ophthalmic Solutions / Q000008:administration & dosage / Q000494:pharmacology*; D011310:Preservatives, Pharmaceutical; D011446:Prospective Studies; D013666:Tears / Q000737:chemistry / Q000378:metabolism; D014792:Visual Acuity / Q000187:drug effects* / Q000502:physiology
chemical_list: D009883:Ophthalmic Solutions; D011310:Preservatives, Pharmaceutical; D002266:Carboxymethylcellulose Sodium