title: Evaluation of corneal stromal demarcation line depth following standard and a modified-accelerated collagen cross-linking protocol.
abstract: OBJECTIVE
  To compare the corneal stromal demarcation line depth using anterior segment optical coherence tomography (AS-OCT) after corneal collagen cross-linking (CXL) using 2 different treatment protocols: the standard Dresden protocol (30 minutes with 3 mW/cm(2)) and a modified-accelerated protocol (14 minutes with 9 mW/cm(2)).
  
  
  METHODS
  Prospective, comparative study.
  
  
  METHODS
  Forty-three keratoconic patients (52 eyes) were enrolled. All patients underwent CXL using the same high-intensity ultraviolet-A (UV-A) irradiation device. Twenty-six eyes were treated for 30 minutes with 3 mW/cm(2) according to the standard Dresden protocol (Group 1), while 26 eyes were treated with a novel modified-accelerated CXL protocol for 14 minutes with 9 mW/cm(2) of UV-A irradiation intensity (Group 2). One month postoperatively, corneal stromal demarcation line depth was measured by 2 independent observers using AS-OCT.
  
  
  RESULTS
  Corneal stromal demarcation line depth was assessed with no significant difference between observer measurements for both groups (P = .676 for Group 1 and P = .566 for Group 2). Mean corneal stromal demarcation line depth was 337.00 ± 46.46 μm for Group 1 and 322.91 ± 48.28 μm for Group 2. There was no statistically significant difference (P = .243) in the corneal stromal demarcation line depth between the 2 groups.
  
  
  CONCLUSIONS
  Corneal stromal demarcation line depth using UV-A with 3 mW/cm(2) for 30 minutes and 9 mW/cm(2) for 14 minutes was similar. A modified-accelerated protocol of 14 minutes of CXL provided the same treatment depth as the classic Dresden protocol.
authors.affiliation: Vardinoyiannion Eye Institute of Crete (VEIC), Faculty of Medicine, University of Crete, Heraklion, Crete, Greece; Bascom Palmer Eye Institute, University of Miami, Miller School of Medicine, Miami, Florida. Electronic address: kymionis@med.uoc.gr.
authors.forename: George D
authors.initials: GD
authors.lastname: Kymionis
authors.affiliation: Vardinoyiannion Eye Institute of Crete (VEIC), Faculty of Medicine, University of Crete, Heraklion, Crete, Greece.
authors.forename: Konstantinos I
authors.initials: KI
authors.lastname: Tsoulnaras
authors.affiliation: Vardinoyiannion Eye Institute of Crete (VEIC), Faculty of Medicine, University of Crete, Heraklion, Crete, Greece.
authors.forename: Michael A
authors.initials: MA
authors.lastname: Grentzelos
authors.affiliation: Vardinoyiannion Eye Institute of Crete (VEIC), Faculty of Medicine, University of Crete, Heraklion, Crete, Greece.
authors.forename: Dimitrios A
authors.initials: DA
authors.lastname: Liakopoulos
authors.affiliation: Vardinoyiannion Eye Institute of Crete (VEIC), Faculty of Medicine, University of Crete, Heraklion, Crete, Greece.
authors.forename: Nikolaos G
authors.initials: NG
authors.lastname: Tsakalis
authors.affiliation: Vardinoyiannion Eye Institute of Crete (VEIC), Faculty of Medicine, University of Crete, Heraklion, Crete, Greece.
authors.forename: Styliani V
authors.initials: SV
authors.lastname: Blazaki
authors.affiliation: Vardinoyiannion Eye Institute of Crete (VEIC), Faculty of Medicine, University of Crete, Heraklion, Crete, Greece.
authors.forename: Theodoros A
authors.initials: TA
authors.lastname: Paraskevopoulos
authors.affiliation: Vardinoyiannion Eye Institute of Crete (VEIC), Faculty of Medicine, University of Crete, Heraklion, Crete, Greece.
authors.forename: Miltiadis K
authors.initials: MK
authors.lastname: Tsilimbaris
mesh_terms: D000293:Adolescent; D000328:Adult; D003094:Collagen / Q000378:metabolism; D063171:Corneal Pachymetry; D003319:Corneal Stroma / Q000378:metabolism / Q000473:pathology*; D003432:Cross-Linking Reagents / Q000627:therapeutic use*; D005260:Female; D006801:Humans; D007640:Keratoconus / Q000188:drug therapy* / Q000378:metabolism / Q000473:pathology; D008297:Male; D008875:Middle Aged; D017319:Photosensitizing Agents / Q000627:therapeutic use; D011446:Prospective Studies; D012256:Riboflavin / Q000627:therapeutic use; D041623:Tomography, Optical Coherence; D014466:Ultraviolet Rays; D055815:Young Adult
chemical_list: D003432:Cross-Linking Reagents; D017319:Photosensitizing Agents; D003094:Collagen; D012256:Riboflavin