Experimental uveitis can be maintained in rabbits for a period of six weeks after a safe sensitization method.

PURPOSE: New treatments against long-lasting uveitis need to be tested. Our aim was to develop a six-week model of uveitis in rabbits. METHODS: Rabbits were presensitized with an s.c. injection of Mycobacterium tuberculosis H37RA emulsified with TiterMax Gold adjuvant. Uveitis was induced at day 28 and 50, by intravitreal challenges of antigen suspension. Ocular inflammation was assessed till euthanasia at day 71 after s.c. injection of M. tuberculosis H37RA by: (a) the number of inflammatory cells in aqueous humor (AH); (b) the protein concentration in AH; (c) the clinical score (mean of conjunctival hyperaemia, conjunctival chemosis, oedema and secretion); (d) the microscopical score (mean presence of fibrin and synechiae, aqueous cell density and aqueous flare grade, as scored by slit lamp). RESULTS: At the sites of presensitization injection, rabbits presented flat nodules which progressively vanished. The first challenge induced a significant increase in the four parameters (p < 0.05 the Wilcoxon/Kruskal-Wallis test). The AH contained 764 ± 82 cells/µl and 32 ± 0.77 mg protein/ml. During the following days, inflammatory parameters decreased slightly. The second intravitreal challenge increased inflammation (3564 ± 228 cells/µl AH and 31 ± 1 mg protein/ml), which remained at a high level for a longer period of time. CONCLUSION: We developed a model of long-term uveitis, which could be maintained in rabbits for at least six weeks. Such a model could be used to test the efficacy of either new drugs or various drug delivery systems intended to deliver active agents during a few months.

Indocyanine green angiography findings in acute retinal necrosis syndrome.

BACKGROUND: Acute retinal necrosis syndrome is clinically defined by the presence of peripheral necrotizing retinitis associated with severe occlusive vasculitis caused primarily by herpes simplex virus and varicella zoster virus. Previously considered as an exclusively retinal pathology, choroidal involvement, as demonstrated by indocyanine green angiography, has not been extensively studied. HISTORY AND SIGNS: Indocyanine green angiography was performed in 4 patients with ARN. Observed angiographic patterns included: 1. a characteristic triangular area of hypo-perfusion, 2. hypofluorescent lobular patches and areas of fuzzy choroidal vascular hyperfluorescence, and 3. isolated hypofluorescent lobular patches of the contralateral eye. THERAPY AND OUTCOME: Marked choroidal hypo-perfusion on indocyanine green angiography was associated with extensive retinal ischemia. Treatment included a combination of antiviral agents and corticosteroids complemented by prophylactic acetylsalicylate. CONCLUSION: Indocyanine green angiography may provide important information regarding choroidal vascular involvement in ARN. It may also permit the timely identification of sub-clinical contralateral eye involvement.

[Branch retinal artery occlusion as the sole ocular manifestation of Takayasu arteritis]. / Occlusion de branche artérielle rétinienne comme manifestation oculaire isolée d'une maladie de Takayasu.

We report a case of branch retinal artery occlusion in a young woman suffering from established Takayasu arteritis. A 35-year-old woman with a previous history of Takayasu arteritis, diagnosed 5 years before, presented to the emergency department reporting sudden visual loss in her left eye and restriction of the visual field for the past hour. On ophthalmologic examination, occlusion of the superior temporal branch of the central retinal artery was revealed. However, no other classic signs of ocular ischemia associated with Takayasu arteritis were observed. Three out of the six criteria set out by the American College of Rheumatology for the diagnosis of Takayasu disease were met. Visual acuity recovered to 7/10(e), corrected, with the presence of a patent cilioretinal artery. The occurrence of retinal artery occlusion at such a young age is exceptional, justifying a thorough examination to reveal the underlying pathology. There is only one other report in the literature of a case of branch retinal artery occlusion as a manifestation of Takayasu arteritis. The case reported here is exceptional because of the absence of more typical signs of ocular ischemia and the moderate degree of involvement of the major cervical arteries.