Ultraviolet C (UV-C) Light Therapy Inhibits Pathogens Associated With Equine Keratomycosis at Different Corneal Depths-An Ex Vivo Study.
Abstract: To assess if an inexpensive, commercially available ultraviolet C (UV-C) light device with a peak emission of 275 nm can inhibit equine keratomycosis-associated pathogens located at different corneal depths in an ex vivo model. Methods: A controlled, randomized experimental design. Aspergillus fumigatus and Fusarium solani isolates were inoculated in fresh bovine corneoscleral transplants, superficially or at 450 μm of stromal depth for the ulcerative keratomycosis or stromal abscess model, respectively. After a minimum of 18 h of incubation, treatment groups received 15 s of UV-C light exposure at a 10 mm distance from the corneal surface level (22.5 mJ/cm dose). Fungal inactivation was quantified by determining the mean fluorescent intensity (MFI) of two fungal viability markers (SYTO 9 = green = alive; PI = red = dead) utilizing confocal laser scanning microscopy. Results: UV-C treatment resulted in statistically significantly higher MFI-PI, lower MFI-SYTO 9 and lower normalized MFI ratios (SYTO 9/[SYTO 9 + PI]) compared to controls for both isolates irrespective of corneal depth; therefore demonstrating successful fungal inactivation. In superficial location, fungal inhibition reached 88% for both isolates. At deeper corneal depth, fungal inhibition was not significantly different for F. solani (84%) but significantly less complete for A. fumigatus (60%). Conclusions: Corneal UV-C light treatment may offer therapeutic benefits for ulcerative keratomycosis and stromal abscesses in the equine species using doses expected to be safe for corneal exposure based on previously published safety data. Species-specific safety studies are required to ensure that antifungal efficacy aligns with safe clinical practice.
© 2025 The Author(s). Veterinary Ophthalmology published by Wiley Periodicals LLC on behalf of American College of Veterinary Ophthalmologists.
Publication Date: 2025-12-15 PubMed ID: 41399192PubMed Central: PMC12963518DOI: 10.1111/vop.70110Google Scholar: Lookup
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Cite This Article
APA
Hoerdemann M, Sahoo DK, Allbaugh RA, Kubai MA.
(2025).
Ultraviolet C (UV-C) Light Therapy Inhibits Pathogens Associated With Equine Keratomycosis at Different Corneal Depths-An Ex Vivo Study.
Vet Ophthalmol, 29(2), e70110.
https://doi.org/10.1111/vop.70110 Publication
Researcher Affiliations
- Department of Veterinary Clinical Sciences, College of Veterinary Medicine, Iowa State University, Ames, Iowa, USA.
- Department of Veterinary Clinical Sciences, College of Veterinary Medicine, Iowa State University, Ames, Iowa, USA.
- Department of Veterinary Clinical Sciences, College of Veterinary Medicine, Iowa State University, Ames, Iowa, USA.
- Department of Veterinary Clinical Sciences, College of Veterinary Medicine, Iowa State University, Ames, Iowa, USA.
MeSH Terms
- Animals
- Horses
- Horse Diseases / microbiology
- Horse Diseases / radiotherapy
- Fusarium / radiation effects
- Aspergillus fumigatus / radiation effects
- Cattle
- Ultraviolet Rays
- Keratitis / veterinary
- Keratitis / microbiology
- Keratitis / radiotherapy
- Ultraviolet Therapy / veterinary
- Fusariosis / veterinary
- Fusariosis / radiotherapy
- Fusariosis / microbiology
- Eye Infections, Fungal / veterinary
- Eye Infections, Fungal / radiotherapy
- Eye Infections, Fungal / microbiology
- Cornea / microbiology
- Cornea / radiation effects
- Aspergillosis / veterinary
- Aspergillosis / radiotherapy
- Aspergillosis / microbiology
Grant Funding
- 028567-00001 / International Equine Ophthalmology Consortium
- CVM PG105121 / Iowa State University
Conflict of Interest Statement
The authors have not used AI to generate any part of the manuscript. Stockyard consent for the harvest and use of ocular tissues for research purposes was obtained. The authors received approval (IBC‐23‐006) from the Iowa State University Institutional Biosafety Committee for the study. Prior to further processing, a brief ophthalmic examination was conducted by an ophthalmology resident (MH) to examine the globes for any evidence of trauma or pre‐existing corneal or intraocular disease that led to exclusion from the study. The authors declare no conflicts of interest.
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