title: One-Year Follow-Up of Changes in Corneal Densitometry After Accelerated (45 mW/cm2) Transepithelial Corneal Collagen Cross-Linking for Keratoconus: A Retrospective Study.
abstract: OBJECTIVE
  The objective of this study is to investigate changes in corneal densitometry after accelerated transepithelial corneal collagen cross-linking (ATE-CXL) for patients with progressive keratoconus (KC).
  
  
  METHODS
  Seventeen progressive KC patients who underwent ATE-CXL (KC group) were examined and compared against 17 non-KC myopes (control group). For the KC group, corneal topography and densitometry were evaluated preoperatively and at 1, 6, and 12 months postoperatively. Manifest refraction spherical equivalent and best spectacle-corrected distant visual acuity were assessed preoperatively and at 12 months postoperatively. These parameters were also evaluated in the control group.
  
  
  RESULTS
  Preoperatively, in the KC group, the densitometry values of the total layer over the annular diameters (Φ) 0 to 2 and Φ 2 to 6 mm were 18.47 ± 1.81 and 16.62 ± 1.60, respectively. In the control group, the values were 14.98 ± 1.18 and 13.39 ± 1.33, respectively, significantly lower than those of the KC group (both post hoc P values < 0.001). At postoperative month 12, the densitometry values of Φ 0 to 2 and Φ 2 to 6 mm of the total layer in the KC group were 16.88 ± 1.57 and 15.28 ± 1.40, which were significantly lower than the preoperative values (post hoc P = 0.012 and 0.030, respectively). However, they were still higher than those of the myopes (post hoc P = 0.002 and 0.001, respectively).
  
  
  CONCLUSIONS
  KC patients have much higher corneal densitometry values than myopes without KC. The KC patients' corneal densitometry values decreased significantly when measured at 12 months after ATE-CXL. However, they remain higher than those of the myopes.
authors.affiliation: *Department of Ophthalmology, The Eye and ENT Hospital of Fudan University, Shanghai, China; and †The Key Lab of Myopia, Ministry of Health, People's Republic of China.
authors.forename: Yang
authors.initials: Y
authors.lastname: Shen
authors.forename: Weijun
authors.initials: W
authors.lastname: Jian
authors.forename: Ling
authors.initials: L
authors.lastname: Sun
authors.forename: Meng
authors.initials: M
authors.lastname: Li
authors.forename: Tian
authors.initials: T
authors.lastname: Han
authors.forename: Jooyeon
authors.initials: J
authors.lastname: Son
authors.forename: Xingtao
authors.initials: X
authors.lastname: Zhou
mesh_terms: D000328:Adult; D003094:Collagen / Q000378:metabolism*; D003319:Corneal Stroma / Q000378:metabolism*; D019781:Corneal Topography; D003432:Cross-Linking Reagents; D003720:Densitometry; D019573:Epithelium, Corneal; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007640:Keratoconus / Q000188:drug therapy* / Q000378:metabolism / Q000503:physiopathology; D008297:Male; D010778:Photochemotherapy; D017319:Photosensitizing Agents; D012029:Refraction, Ocular / Q000502:physiology; D012189:Retrospective Studies; D012256:Riboflavin / Q000627:therapeutic use*; D014466:Ultraviolet Rays; D014792:Visual Acuity / Q000502:physiology; D055815:Young Adult
chemical_list: D003432:Cross-Linking Reagents; D017319:Photosensitizing Agents; D003094:Collagen; D012256:Riboflavin