Antiphospholipid antibody associated retinal microvascular impairment: a case report and literature review.

Ocular involvement in antiphospholipid syndrome typically manifests as retinal artery or vein occlusions. Isolated progressive retinal microvascular impairment as associated with antiphospholipid antibodies (aPL) is rare and poorly characterised.This study is a retrospective case report and literature review. A 35-year-old male presented with bilateral progressive retinal microvascular impairment as the sole clinical manifestation, characterised by concentric capillary dropout beginning in the far periphery and extending towards the juxtafoveal region, accompanied by progressive enlargement of the foveal avascular zone. Laboratory tests confirmed persistently elevated anti-beta-2-glycoprotein-1 IgM. Ultra-widefield fluorescein angiography and optical coherence tomography angiography comprehensively documented the microvascular impairment. Despite sequential treatment with pan-retinal photocoagulation, antiplatelet, anticoagulant and immunosuppressive therapies, microvascular deterioration progressed. Scattered recanalisation of occluded microvasculature was observed following the introduction of sirolimus.This case provides longitudinal in vivo evidence for the involvement of aPL in the pathogenesis of progressive retinal microcirculatory compromise. The advancement of ocular imaging techniques, especially ultra-widefield angiography and optical coherence tomography angiography, is critical for the recognition and characterisation of this microvascular phenotype, which may expand the clinical spectrum of aPL-related microvascular diseases.