Effects of age, sex, and axial length on macular structure and perfusion in normal eyes

This study aimed to investigate how age, sex, refractive error, and axial length are related to macular structure and perfusion in normal eyes. This retrospective, cross-sectional study included 297 eyes of 297 patients without ocular diseases other than cataract who presented to Teine Keijinkai Hospital. All subjects underwent optical coherence tomography (OCT) and OCT angiography. Multiple regression analysis was performed with retinal thickness and perfusion density in the 9 Early Treatment Diabetic Retinopathy Study subfields as dependent variables, and age, sex, refractive error, and axial length as independent variables. Results showed that older age was associated with decreased retinal thickness in most regions excluding the central region, and decreased perfusion density in all regions (P < .05). Females had significantly thinner retinas in all regions (P < .05) but showed no significant difference in perfusion density. Longer axial length was associated with increased retinal thickness in the central region (P < .05), whereas it was linked to decreased values for both thickness and perfusion density in the outer regions (P < .05). Refractive error was not correlated with either parameter. In conclusion, retinal thickness and perfusion density in normal eyes are significantly associated with age, sex, and axial length. Considering these physiological factors is essential for the accurate interpretation of OCT and OCT angiography data in clinical practice.