title: A short-term study of corneal collagen cross-linking with hypo-osmolar riboflavin solution in keratoconic corneas.
abstract: OBJECTIVE
  To report the 3mo outcomes of collagen cross-linking (CXL) with a hypo-osmolar riboflavin in thin corneas with the thinnest thickness less than 400 µm without epithelium.
  
  
  METHODS
  Eight eyes in 6 patients with age 26.2±4.8y were included in the study. All patients underwent CXL using a hypo-osmolar riboflavin solution after its de-epithelization. Best corrected visual acuity, manifest refraction, the thinnest corneal thickness, and endothelial cell density were evaluated before and 3mo after the procedure.
  
  
  RESULTS
  The mean thinnest thickness of the cornea was 408.5±29.0 µm before treatment and reduced to 369.8±24.8 µm after the removal of epithelium. With the application of the hypo-osmolar riboflavin solution, the thickness increased to 445.0±26.5 µm before CXL and recover to 412.5±22.7 µm at 3mo after treatment, P=0.659). Before surgery, the mean K-value of the apex of the keratoconus corneas was 57.6±4.0 diopters, and slightly decreased (54.7±4.9 diopters) after surgery (P=0.085). Mean best-corrected visual acuity was 0.55±0.23 logarithm of the minimal angle of resolution, and increased to 0.53±0.26 logarithm after surgery (P=0.879). The endothelial cell density was 2706.4±201.6 cells/mm(2) before treatment, and slightly decreased (2641.2±218.2 cells/mm(2)) at last fellow up (P=0.002).
  
  
  CONCLUSIONS
  Corneal collagen cross-linking with a hypo-osmolar riboflavin in thin corneas seems to be a promising treatment. Further study should be done to evaluate the safety and efficiency of CXL in thin corneas for the long-term.
authors.affiliation: Department of Ophthalmology, Shandong Provincial Hospital Affiliated to Shandong University, Jinan 250021, Shandong Province, China.
authors.forename: Shao-Feng
authors.initials: SF
authors.lastname: Gu
authors.affiliation: Department of Ophthalmology, Shandong Provincial Hospital Affiliated to Shandong University, Jinan 250021, Shandong Province, China.
authors.forename: Zhao-Shan
authors.initials: ZS
authors.lastname: Fan
authors.affiliation: Department of Ophthalmology, Shandong Provincial Hospital Affiliated to Shandong University, Jinan 250021, Shandong Province, China.
authors.forename: Li-Hua
authors.initials: LH
authors.lastname: Wang
authors.affiliation: Department of Ophthalmology, Shandong Provincial Hospital Affiliated to Shandong University, Jinan 250021, Shandong Province, China.
authors.forename: Xiang-Chen
authors.initials: XC
authors.lastname: Tao
authors.affiliation: Department of Ophthalmology, Shandong Provincial Hospital Affiliated to Shandong University, Jinan 250021, Shandong Province, China.
authors.forename: Yong
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: Department of Ophthalmology, Shandong Provincial Hospital Affiliated to Shandong University, Jinan 250021, Shandong Province, China.
authors.forename: Chun-Qin
authors.initials: CQ
authors.lastname: Wang
authors.affiliation: Department of Ophthalmology, Shandong Provincial Hospital Affiliated to Shandong University, Jinan 250021, Shandong Province, China.
authors.forename: Ya
authors.initials: Y
authors.lastname: Wang
authors.affiliation: Department of Ophthalmology, Shandong Provincial Hospital Affiliated to Shandong University, Jinan 250021, Shandong Province, China.
authors.forename: Guo-Ying
authors.initials: GY
authors.lastname: Mu
keywords: corneal collagen cross-linking; hypo-osmolar riboflavin; keratoconus; thin corneas