Treatment of bullous keratopathy with corneal collagen cross-linking in two dogs
Objective Corneal collagen cross-linking with riboflavin and UV-A (CXL) decreases corneal oedema and increases visual acuity in human patients with bullous keratopathy. Presumed mechanisms are an increase in collagen packing density and a reduction in stromal swelling pressure. We present two cases in which CXL was used to treat bullous keratopathy in dogs. Procedures Four eyes of two dogs with painful bullous keratopathy-induced corneal erosions that were resistant to prior therapy were
... therapy were treated with CXL. Both corneas of the second patient were dehydrated to AE 400 lm corneal thickness using topical 70% glycerol solution immediately prior to CXL. Follow-up included slit-lamp examination, fluorescein staining and photographic documentation in both cases and highresolution ultrasound examination in the second patient. Results All four eyes were comfortable and fluorescein negative at 1-week post-CXL and remained so for the rest of the follow-up period (17.5 months for case 1 and 6 months for case 2). The owner of the first patient reported a less oedematous cornea and improvement in vision that lasted for 6 months. Despite a reported lack of improvement in vision in the second patient, corneal thickness initially decreased, but was back at baseline thickness at the 4-month recheck. Conclusions Similar to humans, CXL might become a useful treatment option for bullous keratopathy-induced therapy-resistant corneal erosions in dogs. Patient comfort was greatly improved, but corneal thickness decrease was not as long-lasting as reported for humans. The presently used protocols might need modification to fit the dog cornea.