Traumatic phacocele in an American Miniature Horse

Abstract

An 18-year-old American Miniature Horse mare was presented with a complaint of a scleral swelling affecting the right eye and a history of suspected trauma 6 weeks prior to evaluation. Clinical findings included severe blepharospasm, a bulbous swelling of the dorsotemporal bulbar conjunctiva, and phthisis bulbi. Ocular ultrasound was recommended but declined. Enucleation was elected for the blind, painful eye and was performed standing. Gross and histopathologic examinations of the globe were consistent with extrusion of the lens to the episcleral space, which is classified as a traumatic phacocele when associated with naturally occurring trauma. The location of lens entrapment suggested globe rupture occurred at the limbus, which is described as one of the weakest points of the equine globe. Subconjunctival dislocation of the lens and development of a traumatic phacocele should be considered as a differential diagnosis for horses presenting with subconjunctival masses, apparent aphakia, and historical trauma.

Clinical findings associated with blunt ocular trauma in horses: a retrospective analysis

“…Signs seen with previously reported blunt orbital and ocular trauma in equids include orbital fracture, 7,9–12 eyelid lacerations and swelling 8,11,13 subconjunctival hemorrhage, chemosis, corneal abrasion, hyphema, 3–5,7,8,10,11,13,14 Descemet's membrane separation, 15 uveitis, 5,7,11,14,16 avulsed corpora nigra, 5,16,17 lens subluxation or luxation, 5,7,11,12 phacoceles, 13 cataract development, 7,9,14,18 vitreal hemorrhage, 11 retinal hemorrhage, 11 retinal tears or detachments, 11,19 scleral ruptures, 5,7–9 and secondary glaucoma 14…”