title: Impression cytologic analysis after corneal collagen cross-linking using riboflavin and ultraviolet-A light in the treatment of keratoconus.
abstract: OBJECTIVE
  To report impression cytologic (IC) results after corneal cross-linking (CXL) using riboflavin and ultraviolet-A light in the treatment of keratoconus and compare the data with those from a group of subjects with the same disease.
  
  
  METHODS
  Forty eyes were distributed into 2 groups: patients in group 1 underwent CXL, whereas patients in group 2 received riboflavin 0.1% eyedrops for 1 month of topical use. IC specimens were obtained from all eyes before treatment and 1 and 3 months after treatment.
  
  
  RESULTS
  Patients in group 1 showed a decrease in goblet cell density on the superior conjunctiva after CXL (P = 0.008) but no difference on the temporal conjunctiva or in the cornea. Patients in group 2 demonstrated improvement in cell-to-cell contact of epithelial cells and reduced keratinization on the temporal conjunctiva after treatment (P = 0.003 and P = 0.034, respectively) but no changes on the superior conjunctiva or in the cornea. Fisher exact test comparison of IC total scores after treatment revealed no difference between groups.
  
  
  CONCLUSIONS
  Despite changes in goblet cell density after corneal CXL in the superior conjunctiva and an improvement in the morphology of epithelial cells after the use of riboflavin eyedrops, comparison of total IC scores showed no difference between groups.
authors.affiliation: Vision Institute, Department of Ophthalmology, Federal University of São Paulo, São Paulo, Brazil. adimararenesto@uol.com.br
authors.forename: Adimara da Candelaria
authors.initials: Ada C
authors.lastname: Renesto
authors.forename: Jeison de Nadai
authors.initials: Jde N
authors.lastname: Barros
authors.forename: Mauro
authors.initials: M
authors.lastname: Campos
mesh_terms: D000293:Adolescent; D000328:Adult; D002452:Cell Count; D003094:Collagen / Q000378:metabolism*; D003228:Conjunctiva / Q000473:pathology*; D003319:Corneal Stroma / Q000378:metabolism*; D019781:Corneal Topography; D005260:Female; D020397:Goblet Cells / Q000473:pathology*; D006801:Humans; D007640:Keratoconus / Q000188:drug therapy* / Q000378:metabolism; D008297:Male; D008875:Middle Aged; D010778:Photochemotherapy; D017319:Photosensitizing Agents / Q000627:therapeutic use; D011446:Prospective Studies; D012256:Riboflavin / Q000627:therapeutic use*; D041623:Tomography, Optical Coherence; D014466:Ultraviolet Rays; D014792:Visual Acuity / Q000502:physiology; D055815:Young Adult
chemical_list: D017319:Photosensitizing Agents; D003094:Collagen; D012256:Riboflavin