Corneal collagen cross-linking as treatment for infectious and noninfectious corneal melting in cats and dogs: results of a prospective, nonrandomized, controlled trial

Vet Ophthalmol. 2014 Jul;17(4):250-60. doi: 10.1111/vop.12090. Epub 2013 Aug 14.


Objective: UV-A/Riboflavin cross-linking of corneal collagen fibers (CXL) is a highly promising therapy for corneal melting in humans. A prospective interventional, nonrandomized, controlled study was conducted to compare the stabilizing effect of CXL treatment on melting keratitis in dogs and cats and the complication rate of CXL to those of standardized intensive medical treatment.

Procedures: Forty-nine eyes with melting keratitis were included in the study between October 2009 and October 2012. All eyes were treated according to the same medical treatment protocol. Nineteen eyes were CXL-treated, and 30 eyes were not. Follow-up included slit-lamp examination, fluorescein staining, ulcer size measurement, stromal stability evaluation, photographic documentation, and documentation of complications.

Results: Five of 19 eyes in the CXL group and 9/30 eyes in the control group required rescue stabilization due to continued melting. Seven of the nine control group corneas stabilized after rescue CXL treatment. At initial presentation, the ulcers in the canine CXL group were significantly deeper and larger than in the control group. Ulcer deepening during follow-up was more pronounced in the canine control group than in the canine CXL group. CXL treatment-related complications were not observed.

Conclusions: Based on the similar failure rates in the control and CXL treatment groups despite the poorer initial situation in the CXL group, the tendency for the ulcers in the control group to deepen and the stabilization of all corneas receiving CXL rescue treatment, we believe that CXL has its place as an adjunctive therapy for melting keratitis in veterinary ophthalmology.

Keywords: cat; cornea; corneal collagen cross-linking; dog; medical therapy; melting keratitis.

Publication types

  • Controlled Clinical Trial

MeSH terms

  • Animals
  • Cat Diseases / therapy*
  • Cats
  • Collagen / chemistry
  • Collagen / metabolism*
  • Cross-Linking Reagents / administration & dosage
  • Cross-Linking Reagents / therapeutic use
  • Dextrans / administration & dosage
  • Dextrans / therapeutic use
  • Dog Diseases / therapy*
  • Dogs
  • Female
  • Male
  • Riboflavin / therapeutic use
  • Ultraviolet Therapy / methods
  • Ultraviolet Therapy / veterinary*
  • Vitamin A Deficiency / therapy
  • Vitamin A Deficiency / veterinary*


  • Cross-Linking Reagents
  • Dextrans
  • Collagen
  • Riboflavin

Supplementary concepts

  • Keratomalacia