Ophthalmic Manifestations of Sickle Cell Disease

Sickle cell disease (SCD), the most common inherited blood disorder, is characterized by defective oxygen transport. Every part of the eye can be affected by microvascular occlusions from SCD; however, the major cause of vision loss is proliferative sickle cell retinopathy (PSR). Although individuals with the HbSS genotype of SCD manifest more systemic morbidity and those with the HbSC genotype have a milder clinical course, those with HbSC have an increased risk of developing PSR and resultant vision loss. Sickle cell retinopathy has a variable phenotype, even among individuals with the same genotype. Most patients with SCD maintain good vision because the associated retinopathy occurs in the retinal periphery, and any associated sea fan neovascularization has a high tendency to autoinfarct and regress. Vision loss from PSR is largely preventable via regular retinal examinations and treatment as indicated. Novel retinal imaging techniques such as wide-field fluorescein angiography, spectral domain optical coherence tomography, and optical coherence tomography angiography can identify evidence of retinal microvascular occlusions in most patients with SCD. Further study is necessary to discover which individuals are at highest risk for vision loss, which of these retinal imaging modalities is clinically important, and which systemic treatments may decrease risk of vision loss from sickle cell retinopathy.