The surgical therapy of equine recurrent uveitis]

Equine recurrent uveitis (ERU) is the most frequently encountered cause of eye problems and blindness in horses. Classic treatment of ERU includes mydriatics, corticosteroids and nonsteroidal anti-inflammatory drugs. Despite vigorous topical and systemic treatment, however, in many cases, the prognosis for preserving vision remains poor. Experiences with surgical treatment of chronic endogenous uveitis in human patients have shown that vision-impairing axial opacities in the vitreous body can be removed by pars plana vitrectomy, and that a considerable decrease in the frequency and severity of uveitic relapses results. So far, 11 eyes of 10 horses were subjected to vitrectomy. All horses had suffered from 3 or more uveitic attacks and had a hazy vitreous. In all cases, at discharge from the clinic, the vitreous chamber was less hazy compared to preoperative findings. At follow-up examinations, 8 eyes (8/10) had normal i.o. pressure, and 2 (2/10) had subnormal i.o. pressure and the vitreous chambers were clear or contained only small floaters. Uveitic attacks had not been observed in the operated eyes. Postoperative complications included fibrinous, or fibrinous-haemorrhagic exudate in the anterior chamber of all eyes, and in one eye, a minor haemorrhage in the vitreous chamber. Our preliminary results indicate that pars plana vitrectomy assuring proper case selection and accurate surgical technique, may contribute to improvement of vision and may delay the progression of uveitic complications in horses.