Methodology of easy-to-use horizontally centrifuged platelet-rich fibrin as a topical treatment for equine ulcerative keratitis in 5 horses.

OBJECTIVE

To describe the most efficient topical horizontally centrifuged platelet-rich fibrin (H-PRF) treatment protocol for equine ulcerative keratitis (EUK) that is easy to use, and to report the preliminary concentration of growth factors and cytokines in equine H-PRF.

ANIMALS: 5 client-owned horses diagnosed with EUK were enrolled over an 11-month period.

CLINICAL PRESENTATION: 3 horses were geldings, and 2 were mares. The mean (± SD) age was 5.95 ± 5.01 years. The owners' main goal was to avoid surgery for EUK.

RESULTS

H-PRF was used in 3 different protocols: solid H-PRF, sutured to the EUK area (n = 1); liquid H-PRF, used topically (n = 2); and combined solid H-PRF, placed in the ventral fornix plus liquid H-PRF (n = 2). Unused H-PRF was analyzed for concentration of growth factors and cytokines. Three of 5 eyes (60%) healed with corneal vascularization and granulation tissue (healing rate, 34 ± 16 days), either negative for culture growth (n = 2) or positive for Staphylococcus aureus (n = 1). Two of 5 eyes (40%), both positive for fungal growth, perforated and were enucleated. Solid H-PRF had the highest concentration of growth factors and cytokines, except for IL-6 and tumor necrosis factor-α, which was mildly higher in liquid H-PRF. Systemic flunixin meglumine seemed to lower growth factors and cytokines in H-PRF.

CLINICAL RELEVANCE: The combined H-PRF protocol gave the highest concentration of growth factors and cytokines, which can lead to a healing response with corneal vascularization and granulation tissue. Future studies should evaluate fungal infection and the effect of systemic NSAIDs on H-PRF healing properties.