OBJECTIVE. UV-A/Riboflavin crosslinking of corneal collagen fibers (CXL) is a highly promising therapy for corneal melting in humans. A prospective interventional, non-randomized, 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 9 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. RESULTS.Five of 19 eyes in the CXL group and 9/30 eyes in the control group required 39 rescue stabilization due to continued melting. Seven of the 9 control group corneas stabilized 40 after rescue CXL treatment. At initial presentation, the ulcers in the canine CXL group were 41 significantly deeper and larger than in the control group. Ulcer deepening during follow-up 42 was more pronounced in the canine control group than in the canine CXL group. CXL 43 treatment related complications were not observed. 44 CONCLUSIONS. Based on the similar failure rates in the control and CXL treatment groups 45 despite the poorer initial situation in the CXL group, the tendency for the ulcers in the control 46 group to deepen and the stabilization of all corneas receiving CXL rescue treatment, we 47 believe that CXL has its place as an adjunctive therapy for melting keratitis in veterinary 48 ophthalmology. 49

Future studies in central Europe should focus on the identification of fungal pathogens, susceptibility patterns and the efficacy of antifungal drug therapies.

A large range of fungal mold species was identified including A. fumigatus and E. amstelodami, which have been causative agents of keratomycosis in Switzerland. Best in vitro susceptibility results for these two species were obtained for voriconazole.