Ocular Ultrasonography in Horses

Ocular ultrasonography is a practical and valuable examination tool for horse eyes with anterior opacities that preclude ophthalmoscopy of deeper structures. Ultrasonography is indicated in cases of periocular trauma, exophthalmos, corneal masses, corneal edema and/or infiltrates, cataracts, and anterior uveitis. Transducers of 7 to 10 MHz may be used to identify and characterize cataracts, lens luxation, lens rupture, vitreal opacities, retinal detachment, endophthalmitis, microphthalmos, buphthalmos, and periorbital masses. High-resolution ultrasonography, using frequencies of 20 MHz and greater, provides improved detail of anterior segment structures. Ultrasound image artifacts are common, requiring knowledge of ocular anatomy and basic ultrasonographic principles for accurate interpretation.