title: Simultaneous Topography-Guided Photorefractive Keratectomy and Accelerated Corneal Collagen Cross-Linking for Keratoconus.
abstract: OBJECTIVE
  To study the evolution of visual and refractive outcomes through the first year after simultaneous topography-guided photorefractive keratectomy (t-PRK) and corneal collagen cross-linking (CXL) in keratoconus.
  
  
  METHODS
  This retrospective case series included 85 eyes of 66 patients with a mean age of 26.3 ± 5.7 years, which underwent simultaneous t-PRK with accelerated CXL. Patients were examined for uncorrected distance visual acuity and corrected distance visual acuity (CDVA), flat and steep keratometry readings, and manifest refraction spherical equivalent at 1, 3, 6, and 12 months.
  
  
  RESULTS
  At 12 months, all study parameters demonstrated a statistically significant improvement with uncorrected distance visual acuity 0.46 ± 0.49 logMAR (vs. 0.86 ± 0.39 logMAR preoperatively), CDVA 0.11 ± 0.12 logMAR (vs. 0.41 ± 0.27 logMAR preoperatively), manifest refraction spherical equivalent -2.80 ± 4.47 D (vs. -4.51 ± 4.68 D preoperatively), flat keratometry 43.84 ± 3.24 D (vs. 44.61 ± 3.12 D preoperatively), and steep keratometry 46.05 ± 3.94 D (vs. 48.10 ± 3.68 D preoperatively). Although 90.6% eyes gained 1 or more lines of CDVA, no eyes lost any lines of CDVA. In all, 37.6% of the eyes demonstrated an improvement of 4 or more lines of CDVA with a maximum improvement of 11 lines of CDVA in 1 eye.
  
  
  CONCLUSIONS
  Simultaneous t-PRK with accelerated CXL improved the spherocylindrical refraction and visual function of keratoconus eyes, and the outcomes were stable through 12 months' follow-up. Future studies with longer follow-up and larger data set are necessary to validate the results of the current study and evaluate the long-term safety and efficacy.
authors.affiliation: Ebsaar Eye Surgery Center, Dubai, United Arab Emirates.
authors.forename: Hani
authors.initials: H
authors.lastname: Sakla
authors.forename: Wassim
authors.initials: W
authors.lastname: Altroudi
authors.forename: Gonzalo
authors.initials: G
authors.lastname: Munoz
authors.forename: Yousef
authors.initials: Y
authors.lastname: Sakla
mesh_terms: D000293:Adolescent; D000328:Adult; D003094:Collagen / Q000378:metabolism*; D003131:Combined Modality Therapy; D003319:Corneal Stroma / Q000378:metabolism; D019781:Corneal Topography; D003432:Cross-Linking Reagents; D005500:Follow-Up Studies; D006801:Humans; D007640:Keratoconus / Q000188:drug therapy / Q000378:metabolism / Q000601:surgery / Q000628:therapy*; D054018:Lasers, Excimer / Q000627:therapeutic use*; D018903:Photorefractive Keratectomy / Q000379:methods*; D017319:Photosensitizing Agents / Q000627:therapeutic use*; D012029:Refraction, Ocular / Q000502:physiology; D012189:Retrospective Studies; D012256:Riboflavin / Q000627:therapeutic use; D025321:Surgery, Computer-Assisted; D014466:Ultraviolet Rays; D014792:Visual Acuity / Q000502:physiology; D055815:Young Adult
chemical_list: D003432:Cross-Linking Reagents; D017319:Photosensitizing Agents; D003094:Collagen; D012256:Riboflavin