title: Assessment of corneal topography indices after collagen crosslinking for keratoconus.
abstract: OBJECTIVE
  Riboflavin UVA (collagen crosslinking [CXL]) treatment for keratoconus is a method for stabilizing or improving corneal properties. Our aim was to evaluate changes in corneal topography indices after CXL.
  
  
  METHODS
  A total of 38 eyes of 25 patients (mean age 29.36 ± 9.7 years) were treated with CXL technique. The follow-up period was 36 months. Slit-lamp examination, visual acuity tests, and pachymetry measurements were performed; in order to obtain the following numerical data, corneal topography (TMS-4; Tomey) was used: simulated keratometry (K1, K2), CYL (cylinder value), SAI (surface asymmetry index), IAI (irregular astigmatism index), SRI (surface regulatory index), ACP (average corneal power), and CEI (corneal eccentricity index). Treatments were performed with In-Pro CCL-Lix (Germany) equipment.
  
  
  RESULTS
  The values of mean K1 (p = 0.82), cylinder (p = 0.73), SAI (p = 0.99), IAI (p = 0.82), SRI (p = 0.73), ACP (p = 0.73), K2 (p = 0.8), and CEI (p = 0.99) showed no significant changes at the end of the examination period. Uncorrected visual acuity remained unchanged (p = 0.32). However, best-corrected visual acuity changed from 0.21 ± 0.17 to 0.12 ± 0.11 in logMAR scale, but this deviation was not considered significant (p = 0.08). No change was observed in intraocular pressure (p = 0.79). Cornea remained clear and during follow-up period no corneal thinning was observed (p = 0.78).
  
  
  CONCLUSIONS
  Our results suggest that corneal collagen CXL can be a successful treatment at certain stages of keratoconus, offering a way to stop progression in keratometric indices.
authors.affiliation: Orbident Refractive Surgery and Medical Center, Medical and Health Science Center, Debrecen, Hungary. zhassan@dote.hu
authors.forename: Ziad
authors.initials: Z
authors.lastname: Hassan
authors.forename: Eszter
authors.initials: E
authors.lastname: Szalai
authors.forename: László
authors.initials: L
authors.lastname: Módis
authors.forename: András
authors.initials: A
authors.lastname: Berta
authors.forename: Gábor
authors.initials: G
authors.lastname: Németh
mesh_terms: D000293:Adolescent; D000328:Adult; D003094:Collagen / Q000378:metabolism*; D003315:Cornea / Q000378:metabolism* / Q000503:physiopathology; D019781:Corneal Topography; D003432:Cross-Linking Reagents / Q000627:therapeutic use*; D005260:Female; D006801:Humans; D007640:Keratoconus / Q000188:drug therapy* / Q000378:metabolism / Q000503:physiopathology; D008297:Male; D017319:Photosensitizing Agents / Q000627:therapeutic use; D012029:Refraction, Ocular / Q000502:physiology; D012256:Riboflavin / Q000627:therapeutic use; D014466:Ultraviolet Rays; D055815:Young Adult
chemical_list: D003432:Cross-Linking Reagents; D017319:Photosensitizing Agents; D003094:Collagen; D012256:Riboflavin