Optical Coherence Tomography Findings in Sickle Cell Retinopathy: A Comparative Study at Two Nigerian Teaching Hospitals

Sickle cell retinopathy encompasses a spectrum of vascular and structural retinal changes, and optical coherence tomography (OCT) offers non-invasive, high-resolution characterisation of structural damage that may precede clinically visible retinopathy. This study compares OCT findings between patients with sickle cell disease and healthy controls at Lagos University Teaching Hospital and University College Hospital, Ibadan, South West Nigeria. An analytical cross-sectional comparative study will be conducted among 100 sickle cell disease patients (50 HbSS and 50 HbSC genotype) and 100 age and sex-matched healthy controls. Spectral-domain OCT will be used to measure peripapillary retinal nerve fibre layer thickness, macular ganglion cell complex thickness, and central macular thickness. Colour fundus photography will document visible retinopathy stage for correlation. OCT parameters will be compared between groups using independent t-tests and ANOVA, with multivariate regression identifying predictors of OCT structural changes. OCT is increasingly used in sickle cell retinopathy research in high-income countries, demonstrating subclinical ganglion cell layer thinning even in patients without clinically apparent retinopathy. This study introduces OCT-based sickle cell retinopathy assessment to the Nigerian literature, generating normative comparison data and establishing the clinical utility of OCT for early retinopathy detection in resource-limited settings. Recommendations will advocate for OCT integration into routine annual ophthalmic screening for sickle cell disease patients at Nigerian teaching hospitals. Keywords: sickle cell retinopathy, optical coherence tomography, retinal thickness, HbSS, HbSC