Equine ulcerative keratitis with furrow: A review of the outcomes of 72 cases from 1987 to 2015.

Abstract

Ulcerative keratitis with peripheral furrow formation is a poorly-described condition which has been associated with a grave prognosis due to rapid necrosis of the cornea. To describe the infectious aetiologies associated with furrow-forming ulcerative keratitis, its overall clinical course and the efficacy of medical and surgical intervention in horses. Retrospective clinical case series. Medical records of 72 horses which presented with furrow-forming ulcerative keratitis at the University of Florida between 1987 and 2015 were reviewed. Seventy-two horses (72 eyes) with furrow-forming ulcerative keratitis were treated at the University of Florida between 1987 and 2015. Of these, a definitive aetiologic diagnosis was available for 37 eyes. Ten of 37 eyes (27%) were diagnosed with fungal keratitis based on cytology of corneal scraping, culture, histopathology and/or fungal PCR. Fourteen of 37 eyes (38%) were diagnosed with a mixed fungal and bacterial keratitis. Thirteen of 37 eyes (35%) were diagnosed with bacterial keratitis. Overall, 26 of 72 total eyes were treated with medical therapy alone (36%). Forty-six of 72 eyes were treated medically and surgically (64%). Of the 26 eyes which received medical therapy, 20 healed with a positive visual outcome (77%) and 6 eyes were non-visual (23%). Of the 46 eyes which received surgical intervention, 40 healed with a positive visual outcome (87%), while six eyes were non-visual (13%). Altogether, 60 of 72 eyes healed with a positive visual outcome following medical or surgical treatment of furrow-forming ulcerative keratitis (83%). Twelve of 72 eyes failed treatment (17%), with six eyes requiring enucleation and six globes becoming phthisical after treatment. Inconsistencies in available medical record data due to the large span of time (1987-2015) are inherent in this retrospective study, along with gradual evolution of corneal surgical techniques and medical therapies over the decades. Furrow-forming ulcerative keratitis was associated with a positive visual outcome in 83% of horses treated at the University of Florida between the years 1987 and 2015. Furrow formation may be associated with either fungal or bacterial infection.