title: Morphology of contact lens-induced conjunctival epithelial flaps: a pilot study.
abstract: OBJECTIVE
  Conjunctival epithelial flap (CEF) is a conjunctival condition most commonly seen in silicone hydrogel contact lens wearers. This study utilized impression cytology to investigate the cellular composition and health of CEFs.
  
  
  METHODS
  Nine (9) subjects were enrolled - 3 non-lens wearers, 3 contact lens wearers without CEF, and 3 contact lens wearers with CEFs wearing 8.4/13.8 lotrafilcon A lenses. Impression cytology samples were collected from the flap or similar locations, if CEF was absent, using rectangular 5 mm × 2 mm Millipore HAWP02500 membrane filters. The filters were gently pressed onto the conjunctiva, subsequently fixed in 95% alcohol, stained with hematoxylin-eosin and evaluated under an Olympus IX70 microscope. Measurements of the longest cell and nucleus dimensions were measured on 40 cells from each filter by utilizing NIH Image 1.63.
  
  
  RESULTS
  CEF consisted of multilayers of epithelial and goblet cells and were devoid of inflammatory cells, basement membrane material and stromal tissue. The cytoplasmic and nuclear dimensions were similar within the groups and the cytoplasm-to-nucleus ratio was not different between the flap group and the non-lens wearing group.
  
  
  CONCLUSIONS
  The CEF appeared to be formed by healthy epithelial and goblet cells that have been dislocated from their normal location along the conjunctival surface by the lens edge. No inflammatory cells were present in this contact lens induced condition, which is reported to be associated most commonly with the silicone hydrogel material.
authors.affiliation: Texas Eye Research and Technology Center, University of Houston College of Optometry, Houston, TX, USA. jbergmanson@uh.edu
authors.forename: Jan P G
authors.initials: JP
authors.lastname: Bergmanson
authors.forename: Johanna
authors.initials: J
authors.lastname: Tukler
authors.forename: Norman E
authors.initials: NE
authors.lastname: Leach
authors.forename: Mussaed
authors.initials: M
authors.lastname: Alabdelmoneam
authors.forename: William L
authors.initials: WL
authors.lastname: Miller
mesh_terms: D048429:Cell Size; D003229:Conjunctival Diseases / Q000209:etiology / Q000473:pathology*; D003263:Contact Lenses, Hydrophilic / Q000009:adverse effects*; D004847:Epithelial Cells / Q000473:pathology*; D058752:Free Tissue Flaps / Q000473:pathology*; D020397:Goblet Cells / Q000473:pathology*; D006801:Humans; D020100:Hydrogels; D010865:Pilot Projects; D012828:Silicones; D005466:Fluorocarbons
chemical_list: D020100:Hydrogels; D012828:Silicones; C481129:lotrafilcon A; D005466:Fluorocarbons