Biometric analysis of disc-fovea distance and optic disc diameter in premature infants using wide-field fundus imaging

Retinal biometric parameters such as disc-fovea (DF) distance and optic disc diameter (DD) are widely used to assess retinal vascularization in premature infants, evaluating the severity of retinopathy of prematurity (ROP). However, normative data for these measurements in neonates remain insufficient, and their relationship with ROP or intravitreal ranibizumab treatment is not well established. This study aimed to measure DF, DD, and DF/DD ratio in premature infants between 34 and 40 weeks of postmenstrual age (PMA), and to evaluate whether these parameters are influenced by the presence of ROP or intravitreal ranibizumab injection. A retrospective analysis was performed on wide-field fundus images from 120 premature infants, categorized into three groups: ROP infants treated with ranibizumab, ROP infants with spontaneous regression, and infants without ROP. The mean DD was 1.55 mm, showing no significant change across groups or over time. DF was 4.28-4.62 mm, displaying a decreasing trend with increasing PMA. The DF/DD ratio remained stable (3.05-3.30) across all PMA weeks and groups, with significant intergroup differences observed only at PMA 40 weeks. These findings suggest that these measurements are not significantly affected by ROP or ranibizumab treatment up to PMA 39 weeks.