Assessment of anatomical variations in retina, retinal vessels, retinal nerve fiber layer and macula in emmetropes and myopes using fundus camera and optical coherence tomography

Introduction: Myopia is a prevalent refractive error characterized by axial elongation of the eyeball, frequently resulting in structural alterations within the retina and its microvasculature. Understanding these anatomical variations is crucial for differentiating physiological myopic changes from early pathological conditions such as glaucoma. Materials and Methods: This cross-sectional observational study was conducted over one year on 200 subjects—100 diagnosed myopes and 100 age- and gender-matched emmetropic controls—at Sarojini Naidu Medical College, Agra. Following institutional ethical clearance and informed consent, all participants underwent detailed fundoscopic examination and optical coherence tomography (OCT). Parameters assessed included foveal, macular, perifoveal, and parafoveal thicknesses, retinal nerve fiber layer (RNFL) profiles, and retinal microvascular density. Results: Myopic subjects demonstrated significantly reduced foveal, central foveal, and macular thickness compared to emmetropic controls (p<0.05). Greater degrees of myopia were associated with further thinning, particularly in the superior and inferior perifoveal regions. No significant variation was noted in parafoveal thickness. Retinal microvascular density and circularity index were markedly lower in myopes. Fundoscopic findings such as lattice degeneration, retinal tears, and posterior staphyloma were more frequently observed in the myopic group. Conclusions: The study highlights distinct anatomical changes in myopic eyes, notably thinning in central and perifoveal retinal regions and reduced vascular density. These alterations must be considered during ocular evaluation to avoid misdiagnosis, particularly in distinguishing myopic changes from glaucomatous damage. Keywords: Myopia, Emmetropia, Optical Coherence Tomography, RNFL, Retinal Thickness, Retinal Microvasculature