title: Corneal collagen cross-linking for keratoconus: results of 3-year follow-up in Pakistani population.
abstract: OBJECTIVE
  To assess the effectiveness and safety of corneal collagen cross-linking with riboflavin and ultraviolet A (UV-A) light in arresting the progression of keratoconus.
  
  
  METHODS
  Prospective, nonrandomized experimental study.
  
  
  METHODS
  Seventy-one eyes of 66 patients with progressive keratoconus.
  
  
  METHODS
  Corneal cross-linking was carried out with riboflavin and UV-A light in patients with progressive keratoconus at Al-Shifa Trust Eye Hospital, Pakistan. Standard protocol of cross-linking comprising epithelial debridement, instillation of isotonic riboflavin (0.1%) for 30 minutes, followed by application of UV-A light for 30 minutes with riboflavin was followed. Variables of interest were uncorrected and best corrected visual acuity (BCVA) with spectacles, spherical equivalent refraction, maximum keratometric reading, and central corneal thickness. Three-year results of these variables after cross-linking were analyzed.
  
  
  RESULTS
  Mean age of patients was 19.79 ± 3.71 years; 75.8% were male and 24.2% were female. After 3 years, uncorrected visual acuity improved in 31.0% by mean 2.0 ± 1.06 Snellen lines, remained same in 64.8%, and deteriorated in 4.2% by mean 1.33 ± 0.57 lines. BCVA improved in 56.3% by mean 2.37 ± 1.10 Snellen lines, remained the same in 40.8%, and deteriorated in 2.8% by mean 1.50 ± 0.70 lines. Spherical equivalent refraction decreased in 33.8% by mean 2.29 ± 1.48 D, remained stable in 60.6%, and increased in 5.6% by mean 1.43 ± 0.42 D. Maximum keratometric reading showed mean regression of 2.64 ± 1.42 D in 60.6%, stabilization in 35.2%, and mean progression of 2.0 ± 0.17 D in 4.2%. In 95.8% of cases, progression of keratoconus halted. Central corneal thickness was decreased by mean 10.32 ± 21.19 µm.
  
  
  CONCLUSIONS
  Cross-linking is an effective and safe treatment option in halting the progression of keratoconus.
authors: Al-Shifa Trust Eye Hospital, Jhelum Road, Rawalpindi, Pakistan. Electronic address: drwajidalikhan@yahoo.com.
authors: Wajid Ali
authors: WA
authors: Khan
authors: Al-Shifa Trust Eye Hospital, Jhelum Road, Rawalpindi, Pakistan.
authors: Naima
authors: N
authors: Zaheer
authors: Al-Shifa Trust Eye Hospital, Jhelum Road, Rawalpindi, Pakistan.
authors: Shama
authors: S
authors: Khan
mesh_terms: D000293:Adolescent; D000328:Adult; D003094:Collagen / Q000378:metabolism*; D003319:Corneal Stroma / Q000378:metabolism*; D019781:Corneal Topography; D003432:Cross-Linking Reagents; D005260:Female; D006801:Humans; D007640:Keratoconus / Q000188:drug therapy* / Q000453:epidemiology / Q000378:metabolism; D008297:Male; D010154:Pakistan / Q000453:epidemiology; D010778:Photochemotherapy; D017319:Photosensitizing Agents / Q000627:therapeutic use*; D011446:Prospective Studies; D012256:Riboflavin / Q000627:therapeutic use; D016896:Treatment Outcome; D014466:Ultraviolet Rays; D014792:Visual Acuity / Q000502:physiology; D055815:Young Adult
chemical_list: D003432:Cross-Linking Reagents; D017319:Photosensitizing Agents; D003094:Collagen; D012256:Riboflavin