OPTICAL COHERENCE TOMOGRAPHY ANGIOGRAPHY OF A29 BIRDSHOT CHORIORETINOPATHY COMPLICATED BY RETINAL NEOVASCULARIZATION

Purpose: To describe the quantitative optical coherence tomography angiography analysis of the superficial and deep retinal capillary plexus in a case of A29 birdshot chorioretinopathy (BCR) complicated by retinal neovascularization. Methods: Multimodal retinal imaging, including optical coherence tomography angiography with quantitated vessel density analysis of the superficial and deep retinal capillary plexus, was performed in a case of A29 BCR. Capillary density (mm−1) was defined as the total vessel length (mm) per area (mm2). Results: A 39-year-old healthy white man presented with vitreous hemorrhage and retinal neovascularization at baseline. Clinical presentation was consistent with BCR and human leukocyte antigen testing confirmed A29 positivity. Optical coherence tomography angiography was performed 6 years after the diagnosis and revealed capillary density reduction in the superficial and especially in the deep retinal capillary plexus. Quantitative vessel density analysis was compared with the mean capillary density of 11 age-matched normal eyes and demonstrated 6% and 18% reduction of the superficial plexus in the right and left eyes of our patient, respectively. For the deep plexus, a reduction of 25% and 32% was found in the right and left eyes, respectively. Conclusion: In this patient with BCR, capillary density reduction was most marked at the deep retinal capillary plexus level and may explain the development of retinal neovascularization in this case. Quantitative optical coherence tomography angiography may be a useful tool to study and to monitor retinal microvascular changes in patients with BCR and should be further explored as a biomarker of therapeutic response.