title: Corneal staining and cell shedding during the development of solution-induced corneal staining.
abstract: OBJECTIVE
  This non-dispensing cross-over study was conducted to determine if lenses presoaked in Opti-Free RepleniSH (OFR) or ReNu MultiPlus (RMP) cause solution-induced corneal staining (SICS) and subsequent cell sloughing before the typical 2 h in vivo examination point. METHODS.: Study lenses (PureVision) were worn bilaterally by 13 participants for periods of 15, 30, 60, and 120 min using two different contralateral care regimen pairings. The lens worn on the test eye was soaked overnight in either OFR or RMP and the control eye in Clear Care (CC). After lens removal, corneal staining was rated on a scale of 0 (negligible) to 100 (severe) for four peripheral quadrants and the central region, and the differential global staining score was calculated by subtracting baseline staining scores. Following the staining assessment, corneal cells were collected from the ocular surface using a non-contact irrigation system to determine ocular cell shedding rates.
  
  
  RESULTS
  Differential global staining score with OFR was greater than CC with the differences being statistically significant at 30 and 60 min (p < 0.01). Maximum staining with RMP was significantly greater than OFR and peaked after 60 and 120 min of lens wear (p < 0.01). On average, 710 ± 470 ocular cells were collected after lens wear, with similar shedding seen independent of solution or lens wear duration (p > 0.05).
  
  
  CONCLUSIONS
  SICS occurred earlier but to a significantly lower degree when PureVision lenses were presoaked in OFR compared with RMP, while lenses presoaked in CC did not cause SICS. Ocular surface cell shedding after lens removal was not impacted by lens wear durations of ≤2 h.
authors.affiliation: Centre for Contact Lens Research, School of Optometry, University of Waterloo, 200 University Avenue West, Waterloo, Ontario, Canada. dluensma@uwaterloo.ca
authors.forename: Doerte
authors.initials: D
authors.lastname: Luensmann
authors.forename: Amir
authors.initials: A
authors.lastname: Moezzi
authors.forename: Rachael Claire
authors.initials: RC
authors.lastname: Peterson
authors.forename: Craig
authors.initials: C
authors.lastname: Woods
authors.forename: Desmond
authors.initials: D
authors.lastname: Fonn
mesh_terms: D000328:Adult; D018639:Contact Lens Solutions / Q000494:pharmacology*; D003262:Contact Lenses, Extended-Wear; D003315:Cornea / Q000166:cytology / Q000187:drug effects*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D013194:Staining and Labeling / Q000379:methods*; D055815:Young Adult
chemical_list: D018639:Contact Lens Solutions