Choroidal Thickness in Birdshot Retinochoroiditis Over a 2-Year Period

Abstract

Purpose: To evaluate 2-year choroidal changes in eyes with birdshot retinochoroiditis (BRC).

Methods: Thirteen patients (26 eyes) with BRC were prospectively evaluated during a 2-year period with standard automated perimetry (SAP), fluorescein angiography, indocyanine green angiography and optical coherence tomography (Spectralis Heidelberg Retinal Angiograph + optical coherence tomography). Enhanced-depth imaging optical coherence tomography was performed.

Results: Eight patients (61%) were females; the patients mean age was 60 ± 4.7 (range 49-66) years. At baseline, best-corrected visual acuity (BCVA) was 0.08 ± 0.2 and foveal sensitivity threshold (FST) at SAP was 34.04 ± 2.6; at 2-year visit, no significant changes were observed (BCVA 0.06 ± 02, p = 0.1 and FST 34.36 ± 2.6, p = 0.1). In all cases, at the 2-year visit, a significant reduction of choroidal thickness was present only at the fovea (p = 0.01). The rate of foveal choroidal thinning was 1.8 ± 1.6 µm per month. When compared to baseline, suprachoroidal fluid (SCF) was more frequent (42.3 vs. 23%; p = 0.002). The amount of foveal choroidal thinning was associated with the presence of SCF at baseline (p = 0.005).

Conclusion: In patients with BRC, foveal choroidal thinning and increase of SCF at 2-year follow-up can be observed, even in the absence of visual loss.

Keywords: Birdshot retinochoroiditis; Choroid; Enhanced-depth imaging; Optical coherence tomography.