Purpose
To describe a cohort of patients with birdshot chorioretinopathy (BSCR) who did not manifest characteristic birdshot lesions on clinical examination or fluorescein angiography (FA) but had retinal vasculitis, low-grade to moderate vitritis and hypofluorescent lesions on indocyanine green angiography (ICGA).
Methods
Retrospective chart review.
Results
We present five patients from the Bascom Palmer Eye Institute, the University of Virginia, and Emory University evaluated from 2007 to 2014, with mild-moderate vitritis and retinal vasculitis without evidence of characteristic birdshot lesions on clinical examination. All patients were positive for HLA-A29 and had hypofluorescent lesions visible on ICGA that were not detectable on FA.<br /> <br /> Average age at presentation was 49.8 years (range 40-62). Three patients were female and two were male. All patients presented with bilateral eye disease. Best-corrected presenting visual acuity ranged from 20/20-20/80 OD (median 20/30) and 20/20-20/80 OS (median 20/25). Three patients were successfully managed with steroid-sparing immunosuppressive therapy and one patient was successfully treated using bilateral 0.7mg dexamethasone implant (Ozurdex) injections. A final patient with very mild vitritis declined medical therapy and remained asymptomatic with 20/20 visual acuity through 9 months follow up.<br /> <br /> Characteristic imaging findings of a 46 year old female patient are shown in Figure 1. This patient presented with a six-month history of iridocyclitis unresponsive to topical steroids. BCVA was 20/30 OD and 20/25 OS. Examination was remarkable for rare anterior chamber cell, mild-moderate vitritis, disc edema, and retinal vasculitis OU. Macular edema was absent on clinical examination and OCT. FA demonstrated retinal vasculitis. ICGA confirmed diffuse hypofluorescent lesions consistent with BSCR. HLA A29 testing was subsequently positive. The patient began therapy with mycophenolate mofetil and cyclosporine A, with which her symptoms improved. Retinal vasculitis and vitritis have fully resolved.
Conclusions
Patients with retinal vasculitis and low grade vitritis with or without macular edema may have BSCR evident on ICGA before lesions are visible on clinical examination or FA. Expanding BSCR diagnostic criteria to include the presence of hypocyanescent lesions on ICGA could potentially improve the sensitivity of diagnosis.