title: Stromal Demarcation Line in Pulsed Versus Continuous Light Accelerated Corneal Cross-linking for Keratoconus.
abstract: OBJECTIVE
  To compare the stromal demarcation line depth in pulsed versus continuous corneal cross-linking (CXL) for keratoconus.
  
  
  METHODS
  Seventy eyes underwent epithelium-off cross-linking, with 0.1% riboflavin applied during 10 minutes prior to ultraviolet irradiation at 30 mW/cm2. Thirty-six eyes received pulsed irradiation (1 second on, 1 second off) for 8 minutes and 34 eyes underwent continuous irradiation for 4 minutes. Total fluence was 7.2 J/cm2 for both groups. Patients were evaluated at 3 months after the procedure.
  
  
  RESULTS
  A significantly deeper stromal demarcation line was observed in the pulsed group compared to the continuous group (201.11 ± 27.76 vs. 159.88 ± 20.86 µm; P < .001).
  
  
  CONCLUSIONS
  The pulsed corneal cross-linking protocol induced a significantly deeper stromal demarcation line when compared to the 4 minutes of highly accelerated continuous CXL protocol. Neither CXL protocol induced a shallower demarcation line comparable to less accelerated CXL protocols previously reported.
authors.forename: Alireza
authors.initials: A
authors.lastname: Peyman
authors.forename: Alireza
authors.initials: A
authors.lastname: Nouralishahi
authors.forename: Farhad
authors.initials: F
authors.lastname: Hafezi
authors.forename: Sabine
authors.initials: S
authors.lastname: Kling
authors.forename: Mohamadreza
authors.initials: M
authors.lastname: Peyman
mesh_terms: D000328:Adult; D059925:Anatomic Landmarks; D003094:Collagen / Q000378:metabolism; D003319:Corneal Stroma / Q000187:drug effects / Q000378:metabolism / Q000473:pathology*; D003432:Cross-Linking Reagents; D005260:Female; D006801:Humans; D007640:Keratoconus / Q000175:diagnosis / Q000188:drug therapy* / Q000378:metabolism; D008297:Male; D017319:Photosensitizing Agents / Q000627:therapeutic use*; D011446:Prospective Studies; D012256:Riboflavin / Q000627:therapeutic use; D041623:Tomography, Optical Coherence; D014466:Ultraviolet Rays; D014792:Visual Acuity
chemical_list: D003432:Cross-Linking Reagents; D017319:Photosensitizing Agents; D003094:Collagen; D012256:Riboflavin