title: Cornea Collagen Cross-linking for Keratoconus: A Comparison between Accelerated and Conventional Methods.
abstract: BACKGROUND
  Keratoconus is a progressive degenerative disorder of the cornea in which structural changes in the cornea cause it to become thin and conical in shape. Recently, collagen cross-linking (CXL) has been introduced as an effective intervention in management of progressive keratoconus. Accelerated CXL is a new protocol of this procedure which reduces corneal ultraviolet irradiation exposure time to 5 min. This study aimed to compare visual acuity, keratometry and topographic criteria of keratoconic eyes after conventional and accelerated CXL with a six-month follow-up.
  
  
  METHODS
  In this prospective interventional study we assessed eyes of 40 patients. Patients were divided into two groups randomly. One group underwent accelerated (5 min) CXL and the other underwent conventional (30 min) CXL. Visual acuity, topographic criteria and keratometry were assessed preoperatively and 6 months postoperatively.
  
  
  RESULTS
  In the present study we assessed 40 patients, 50% of which were right eye (OD) and 50% were left eye (OS). Mean age of patients in the accelerated group was 22.10 and in the conventional group was 22.80 years. Our results showed no significant differences between visual acuity, keratometric and topographic criteria in the two groups before intervention. Likewise our results manifested no significant difference between visual acuity, keratometric, refractive and topographic criteria after intervention.
  
  
  CONCLUSIONS
  According to our survey topographic criteria and keratometry improvement in the accelerated and conventional protocol are the same. So accelerated protocol is suggested as a safe and effective option for management of progressive keratoconus.
authors.affiliation: Department of Ophthalmology, Isfahan University of Medical Sciences, Isfahan, Iran.
authors.forename: Hasan
authors.initials: H
authors.lastname: Razmjoo
authors.affiliation: Department of Ophthalmology, Isfahan University of Medical Sciences, Isfahan, Iran.
authors.forename: Alireza
authors.initials: A
authors.lastname: Peyman
authors.affiliation: Department of Ophthalmology, Isfahan University of Medical Sciences, Isfahan, Iran.
authors.forename: Ali
authors.initials: A
authors.lastname: Rahimi
authors.affiliation: Department of Ophthalmology, Isfahan University of Medical Sciences, Isfahan, Iran.
authors.forename: Hoda Jafari
authors.initials: HJ
authors.lastname: Modrek
keywords: Accelerated method; conventional method; cornea collagen cross-linking; keratoconus