title: Customized Corneal Cross-linking: One-Year Results.
abstract: OBJECTIVE
  To compare the efficacy of customized corneal cross-linking (CXL) with standard CXL.
  
  
  METHODS
  Prospective, nonrandomized comparative clinical study.
  
  
  METHODS
  In a prospective study at the Institut für Refraktive und Ophthalmo-Chirurgie (IROC), Zurich, Switzerland, 40 eyes of 40 patients with documented progressive primary keratoconus were treated with customized CXL (n = 20) or standard CXL (n = 20) and followed for 1 year. Customized irradiation patterns had an energy fluence of 9 mW/cm(2) and total energy levels ranging from 5.4 J/cm(2) up to 10 J/cm(2) and were centered on the maximum of the posterior float. The control group received homogenous irradiation with a fluence of 9 mW/cm(2) and a total energy of 5.4 J/cm(2). Scheimpflug tomographies, endothelium cell count, best spectacle-corrected visual acuity (BSCVA), and anterior segment optical coherence tomography (OCT) were compared preoperatively and 1 year postoperatively.
  
  
  RESULTS
  Pachymetry and ΔKmax showed significant changes 1 year postoperatively within each group. Epithelial healing time, ΔKmax, and regularization index (RI) were significantly better in the customized CXL group. Two out of 19 eyes (11%) in the standard group but 7 out of 19 eyes (37%) in the customized CXL group showed a flattening of 2 or more diopters (P = .03). The RI was 5.2 ± 2.7 D in the customized group vs 4.1 ± 3.1 D in the control group (P = .03). Statistically significant correlations between RI and preoperative Kmax, preoperative pachymetry, and preoperative posterior float were found only in the customized group.
  
  
  CONCLUSIONS
  Customized CXL seems to be as safe as standard CXL with stronger flattening in Kmax and RI, and a faster epithelial healing period.
authors.affiliation: Department of Ophthalmology, Inselspital, Universität Bern, Bern, Switzerland; Institut für Refraktive und Ophthalmo-Chirurgie (IROC), Zürich, Switzerland. Electronic address: theo@seiler.tv.
authors.forename: Theo G
authors.initials: TG
authors.lastname: Seiler
authors.affiliation: Department of Ophthalmology, Inselspital, Universität Bern, Bern, Switzerland; Institut für Refraktive und Ophthalmo-Chirurgie (IROC), Zürich, Switzerland.
authors.forename: Isaak
authors.initials: I
authors.lastname: Fischinger
authors.affiliation: Institut für Refraktive und Ophthalmo-Chirurgie (IROC), Zürich, Switzerland.
authors.forename: Tobias
authors.initials: T
authors.lastname: Koller
authors.affiliation: Klinik und Poliklinik für Augenheilkunde, Klinikum rechts der Isar, TU München, Munich, Germany.
authors.forename: Daniel
authors.initials: D
authors.lastname: Zapp
authors.affiliation: Department of Ophthalmology, Inselspital, Universität Bern, Bern, Switzerland.
authors.forename: Beatrice E
authors.initials: BE
authors.lastname: Frueh
authors.affiliation: Institut für Refraktive und Ophthalmo-Chirurgie (IROC), Zürich, Switzerland.
authors.forename: Theo
authors.initials: T
authors.lastname: Seiler
mesh_terms: D000328:Adult; D003094:Collagen / Q000378:metabolism*; D063171:Corneal Pachymetry; D003319:Corneal Stroma / Q000378:metabolism*; D019781:Corneal Topography; D003432:Cross-Linking Reagents; D005260:Female; D006801:Humans; D007640:Keratoconus / Q000188:drug therapy* / Q000378:metabolism / Q000503:physiopathology; D008297:Male; D010778:Photochemotherapy / Q000379:methods*; D017319:Photosensitizing Agents / Q000627:therapeutic use*; D011446:Prospective Studies; D012256:Riboflavin / Q000627:therapeutic use*; D041623:Tomography, Optical Coherence; D016896:Treatment Outcome; D014466:Ultraviolet Rays; D014792:Visual Acuity / Q000502:physiology; D014945:Wound Healing; D055815:Young Adult
chemical_list: D003432:Cross-Linking Reagents; D017319:Photosensitizing Agents; D003094:Collagen; D012256:Riboflavin