title: Keratoconus progression after intrastromal corneal ring segment implantation in young patients: Five-year follow-up.
abstract: OBJECTIVE
  To analyze whether implantation of intrastromal corneal ring segments (ICRS) influences the progression of keratoconus in young patients.
  
  
  METHODS
  Vissum Corporation, Alicante, Spain.
  
  
  METHODS
  Retrospective case series.
  
  
  METHODS
  Eyes with confirmed progressive keratoconus and ICRS (Intacs or Keraring) were evaluated. The visual, refractive, topographic, and aberrometric outcomes were assessed at 2 preoperative examinations to confirm the progressive nature of each case. The postoperative follow-up was 5 years.
  
  
  RESULTS
  The study evaluated 18 eyes in 15 patients with a mean age of 25.75 years ± 3.59 (SD). All the visual, refractive, and topographic measurements worsened between the 2 preoperative examinations, confirming the progressive nature of the cases. Six months postoperatively, there was improvement in the uncorrected and corrected distance visual acuities (P > .05) and all refractive measurements (P < .05) and the mean keratometry (K) was reduced by 4.48 diopters (D) (P < .01). Immediately after the procedure, the visual and refractive variables improved but then worsened. From 6 months postoperatively to 5 years, the mean K value regressed 3.36 D.
  
  
  CONCLUSIONS
  Implantation of ICRS significantly improved the visual, refractive, and topographic parameters in the short term; however, the regression at 5 years suggests that implantation of ICRS does not significantly influence progressive keratoconus in young patients with confirmed progression of the disease.
  
  
  BACKGROUND
  No author has a financial or proprietary interest in any material or method mentioned.
authors.affiliation: From the Keratoconus Unit, Vissum Instituto Oftalmologico de Alicante and the Division of Ophthalmology, Universidad Miguel Hernández, Alicante, Spain.
authors.forename: Alfredo
authors.initials: A
authors.lastname: Vega-Estrada
authors.affiliation: From the Keratoconus Unit, Vissum Instituto Oftalmologico de Alicante and the Division of Ophthalmology, Universidad Miguel Hernández, Alicante, Spain. Electronic address: jlalio@vissum.com.
authors.forename: Jorge L
authors.initials: JL
authors.lastname: Alió
authors.affiliation: From the Keratoconus Unit, Vissum Instituto Oftalmologico de Alicante and the Division of Ophthalmology, Universidad Miguel Hernández, Alicante, Spain.
authors.forename: Ana B
authors.initials: AB
authors.lastname: Plaza-Puche
mesh_terms: D057128:Aberrometry; D000328:Adult; D003319:Corneal Stroma / Q000503:physiopathology / Q000601:surgery*; D019781:Corneal Topography; D018450:Disease Progression; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007640:Keratoconus / Q000503:physiopathology* / Q000601:surgery*; D008297:Male; D019736:Prostheses and Implants; D019919:Prosthesis Implantation; D012029:Refraction, Ocular / Q000502:physiology; D012189:Retrospective Studies; D014792:Visual Acuity / Q000502:physiology; D055815:Young Adult