Lim JI, Niec M, Sun J, et al. - In this longitudinal prospective case-control study, the researchers evaluated the rates of macular thinning in adults with and without sickle cell retinopathy using spectral-domain optical coherence tomography (OCT) and identified ocular and systemic risk factors associated with retinal thinning. Between February 11, 2009, and July 3, 2019, adult participants from a university-based retina subspecialty clinic were recruited. Among 370 adults (711 eyes) recruited in the study, 310 candidates (606 eyes) had sickle cell retinopathy, and 60 candidates (105 eyes) did not. The rates of retinal thinning among participants with sickle cell retinopathy were higher in this study compared with those without sickle cell retinopathy, and the rates of thinning increased with participant age and retinopathy stage. Such results indicate that it may be a useful parameter for evaluating the progression of sickle cell retinopathy to classify anatomic worsening of sickle cell maculopathy by spectral-domain OCT.