Long-term ophthalmologic examinations of eyes with equine recurrent uveitis after pars plana vitrectomy

Abstract

Eva I. A. Baake et al. Pferdeheilkunde -Equine Medicine 35 (2019) 220 Long-term ophthalmologic examinations of eyes with equine recurrent uveitis after pars plana vitrectomy Pferdeheilkunde -Equine MedicineSummary: Equine recurrent uveitis (ERU) is an ocular disease in horses of different breeds with a prevalence between 2.7 and 7.6 % in Europe and vitrectomy is a common method of treatment. The objective of the study was to evaluate the long-term retention of vision and control of uveitis after pars plana vitrectomy performed between 2005 and 2013 on eyes with a history of equine recurrent uveitis (ERU). Vitrectomy in eyes with ERU can influence the recurrent nature of the disease. Previous studies indicated success rates regarding the further absence of uveitis between 73.6 and 97.7 %. Owners of the horses were contacted and an ophthalmological reexamination including tonometry, induction of mydriasis, slit lamp biomicroscopy and direct ophthalmology was performed in 116 horses (147 eyes vitrectomized). Visual acuity was examined by the dazzle reaction and the menace response. Aspects such as gender, age and breed of the horses, as well as leptospiral status and preexisting damage of operated eyes are described. A total of 246 eyes were accessible for follow-up information, whereas 147 eyes were available for ophthalmologic reexaminations. If only the reexamined eyes are considered, an improvement of the condition was seen in 133 eyes (91 %) and 14 eyes (9 %) showed at least one uveitic recurrence after vitrectomy. A positive menace response and a positive dazzle reaction were observed in 128 of the 147 reexamined eyes (87 %). The number of episodes prior to vitrectomy, the gender of the horse and the leptospiral status of the eye showed no significant correlation with the prevalence of recurrences. Coat color, breed and age of the horse operated, and preexisting ocular alterations showed a significant influence on the chance of postoperative recurrences of uveitis. Horses with a coat color other than "chestnut" and "black and brown" had significantly more recurrences and odds ratio for these horses developing recurrences was also significantly higher. The present study shows that a large number of reexamined eyes remained visual (87 %) and a large proportion of the eyes (91 %) showed an improvement of the condition after vitrectomy. Results of this study suggest that genetic factors, age and preexisting ocular alterations influence the long-term prognosis of eyes with ERU after vitrectomy.Citation: Baake E. I. A., von Borstel M., Rohn K., Boevé M. H., Ohnesorge B. (2019) Long-term ophthalmologic examinations of eyes with equine recurrent uveitis after pars plana vitrectomy.

Neutrophil Extracellular Traps in the Pathogenesis of Equine Recurrent Uveitis (ERU)

“…The VBF samples of ERU-diseased horses included in the NET induction assay, ELISA to detect equine cathelicidins, and electron microscopy evaluation were obtained from horses vitrectomized between 2016 and 2018 at the Clinic for Horses of the University of Veterinary Medicine Hannover, Germany. The pre-examinations, treatment, and surgical procedure were performed as previously published by von Borstel et al and Baake et al [6,37]. Remnant VBF samples from diagnostic procedures were used in this study.…”

Results of 654 trans-pars plana vitrectomies of equine eyes with recurrent uveitis – follow-up until 18 years after surgery

“…The frequent detection of leptospiral infections in intraocular samples from eyes suffering from ERU corresponds to the data of other European authors (Brem et al 1998, Wollanke et al 1998b, Wollanke et al 2000, Hartskeerl et al 2004, Niedermaier et al 2006, Brandes et al 2007, Tömördy et al 2010, Baake et al 2016, Dorrego-Keiter et al 2017, Sauvage et al 2018). As published in other studies (Wollanke 2002, Tömördy 2009, Tömördy et al 2010, Baake et al 2019, Voelter et al 2020, the risk of the recurrence of uveitis after vitrectomy seems to be lowest if eyes are tested positive for an intraocular leptospiral infection at the time of surgery. Detection of an intraocular leptospiral infection in uveitic eyes in conjunction with the absence of uveitis after vitrectomy confirms the great importance of an intraocular leptospiral infection in the etiopathogenesis of ERU.…”

“…The results of several studies on the outcome of the vitrectomy in eyes suffering from ERU indicate a significant advancement in its treatment (Winterberg and Gerhards 1997, Frühauf et al 1998, Von Borstel et al 2005, Tömördy et al 2010, Dorrego-Keiter et al 2017, Schinagl 2017, Baake et al 2019, Voelter et al 2020. The aim of this study was to analyse the success of the PPV as a surgical therapy of ERU based on a large number of patients and a long postoperative period.…”

In Vivo Biofilm Formation of Pathogenic Leptospira spp. in the Vitreous Humor of Horses with Recurrent Uveitis

“…In European horses without a leopard coat pattern, the most effective method to prevent further episodes of uveitis and thereby preserve vision is vitrectomy [10,[18][19][20][21]. After a properly performed vitrectomy, which has been routinely performed for more than 30 years in horses with ERU, the control of inflammation is seen in 90-97% of horses [10,13,[21][22][23][24]. By contrast, uveitis in horses with a leopard coat pattern manifests differently.…”