Optic Disk Size and Optic Disk-to-Fovea Distance in Preterm and Full-Term Infants

Abstract

PURPOSE. Few studies have assessed optic disk and retinal morphology in infants. Here the optic disk and optic disk-to-fovea distance were measured in preterm and full-term infants in vivo. METHODS. Optic disk (OD) dimensions and the center-to-center distance between the OD and the macula were measured using digital imaging in infants undergoing routine ophthalmic examinations. Postmenstrual age of the mother at the time of examination ranged from 32 to 50 weeks. From each image, the OD-to-fovea distance (ODF) and the OD height (ODH) and OD width (ODW) were measured. RESULTS. In 51 retinal images from 51 infants, mean Ϯ SD values obtained were 4.4 Ϯ 0.4 mm (ODF), 1.41 Ϯ 0.1 9 mm (ODH), and 1.05 Ϯ 0.13 mm (ODW). These dimensions did not change significantly over the age range studied. The mean value for the ratio between ODF and mean OD diameter (ODF/DD) was 3.76. CONCLUSIONS. Results of this in vivo study suggest that though the optic nerve head diameter increases by more than 50%, only limited growth occurs at the highly organized area of the posterior pole from birth to adulthood. This study discusses the finding of a large-angle kappa in infants and the use of a disk macula/disk diameter ratio in the diagnosis of optic nerve hypoplasia.

Computer-Based Image Analysis for Plus Disease Diagnosis in Retinopathy of Prematurity: Performance of the “i-ROP” System and Image Features Associated With Expert Diagnosis

“…2014;55:ARVO E-Abstract 5929). 20 The segmentation and cropping processes are illustrated in Figure 1.…”

Ophthalmological problems associated with preterm birth

“…19 Later, retinal growth is mainly in the periphery, the disc to macular distance remaining almost constant. 20 Retinal vasculogenesis commences from the optic nerve head circumperipherally before 14 weeks GA, and is replaced at 21 weeks GA by angiogenesis, which is complete by term. There is a trend for an increase in the total vessel angle as the arcades develop through GAs.…”

Absence of age-related optic disk changes in young children with optic nerve hypoplasia

“…Prematurity, uncommon in ONH (11%), 15 was present in just under 7% (n ¼ 1) of our study sample. Contrary to our study methods, the findings by De Silva et al 6 were not based on repeat measurements within the same subjects or at different time points; rather, the infants' measurements were compared with normal adult measurements, despite the cohort's prematurity. The only other study measuring optic disk size of infants from fundus photographs also did not assess reproducibility in measurements.…”

“…5 This can be done subjectively through indirect ophthalmoscopy or objectively by measuring the relative optic disk size on fundus photography. A study by De Silva et al, 6 reporting 51% growth in the optic disk relative to other fundus landmarks between birth and adulthood, raises the question of whether such optic disk measurements require adjustment by age.…”