title: Transepithelial High-Intensity Cross-Linking for the Treatment of Progressive Keratoconus: 2-year Outcomes.
abstract: To report 2-year outcomes of transepithelial high-intensity cross-linking (CXL) procedure in the treatment of patients with progressive keratoconus.
  
  
  
  Forty-eight eyes of 48 consecutive progressive keratoconus patients who underwent transepithelial accelerated CXL procedure were enrolled in the study. Each patient underwent pre- and postoperative comprehensive ophthalmologic examinations including determination of refractive error as spherical equivalent (SE) and corrected distant visual acuity (CDVA), slit lamp biomicroscopic examination, fundoscopy, and a detailed analysis on a Scheimplug+Placido device (Sirius, CSO, Florence, Italy). The riboflavin solution, which was composed of riboflavin 0.25% with hydroxypropyl methylcellulose (HPMC) and benzalkonium chloride (BAC) (ParaCel, Avedro), was used in the procedure. The cornea was exposed to ultraviolet A light (KXL System, Avedro Inc., Waltham, MS, USA) for 2 minutes and 40 seconds at an irradiance of 45 mW/cm2.
  
  
  
  The mean age of the patients was 25.9 ± 4.0 (ranging from 18 to 33) years. No significant changes were observed in the mean CDVA, SE, and topographic indices at year 1 and year 2 visits compared to preoperative examination. The mean corneal thickness at the thinnest point was significantly higher at year 1 and year 2 visits than at preoperative examination (p1 = 0.014 and p2 = 0.017, respectively). No intra- or postoperative complications or adverse reactions were observed.
  
  
  
  Transepithelial high-intensity (irradiance of 45 mW/cm2for 2 minutes and 40 seconds) CXL using 0.25% riboflavin solution was a safe and effective method to halt the progression of keratoconus for a 2-year follow-up period.
authors.affiliation: a Department of Ophthalmology , Kars Harakani State Hospital , Kars , Turkey.
authors.forename: Muhammet Bahattin
authors.initials: MB
authors.lastname: Kır
authors.affiliation: b Department of Ophthalmology , Recep Tayyip Erdoğan University Medical School , Rize , Turkey.
authors.forename: Kemal
authors.initials: K
authors.lastname: Türkyılmaz
authors.affiliation: b Department of Ophthalmology , Recep Tayyip Erdoğan University Medical School , Rize , Turkey.
authors.forename: Veysi
authors.initials: V
authors.lastname: Öner
mesh_terms: D000293:Adolescent; D000328:Adult; D003094:Collagen / Q000378:metabolism; D063171:Corneal Pachymetry; D003319:Corneal Stroma / Q000378:metabolism; D019781:Corneal Topography; D019573:Epithelium, Corneal; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007640:Keratoconus / Q000188:drug therapy* / Q000378:metabolism / Q000503:physiopathology; D008297:Male; D010778:Photochemotherapy / Q000379:methods*; D017319:Photosensitizing Agents / Q000627:therapeutic use*; D012029:Refraction, Ocular; D012256:Riboflavin / Q000627:therapeutic use; D016896:Treatment Outcome; D014466:Ultraviolet Rays; D014792:Visual Acuity / Q000502:physiology; D055815:Young Adult
chemical_list: D017319:Photosensitizing Agents; D003094:Collagen; D012256:Riboflavin
keywords: Cornea; cross-linking; high-intensity; keratoconus; transepithelial