Foveal Morphologic Characteristics in Full-term Neonates by Spectral Domain Optical Coherence Tomography (SD OCT)

Abstract

Purpose: : Optical Coherence Tomography (OCT) is a diagnostic imaging tool widely used for the diagnosis of retinal diseases in adults and older children. Recent studies have shown subclinical findings with Spectral Domain OCT (SDOCT) in neonates with retinopathy of prematurity. A normative database of foveal morphology in full term neonates is not available for reference purposes. This study describes macular morphological characteristics and retinal thickness in full term neonates using SDOCT in the first 48 hours of life.

Methods: : Forty full term neonates in the Duke Birthing Center were enrolled with parental consent. After a dilated ophthalmoscopic exam, SDOCT imaging of the macula was obtained using an FDA approved portable handheld system (Bioptigen Inc., RTP, NC). Images were converted to DICOM format and qualitatively graded by certified SDOCT graders on OSIRIX medical imaging software (OSIRIX Foundation, Geneva, Switzerland) for presence of individual retinal layers at the foveal center and vitreo-retinal pathology. Central foveal thickness was measured semi-automatically using DOCTRAP software (Duke University, NC).

Results: : Thirty nine subjects (78 eyes) were imaged (one subject withdrew study before imaging). Mean gestational age 39.4 weeks (36.1-41.6); mean birth weight 3253 g (2125-3920); 17 (43.6%) were male, 22 (56%) white, 15 (38%) African-American, 1 (2.6%) Hispanic and 1 (2.6%) Asian. On ophthalmoscopic examination 8 subjects (15 eyes) had retinal hemorrhages. On SDOCT, 23 (64%) of subjects (41 eyes) with adequate scan quality had persistent inner retinal layers at the foveal center consisting of inner nuclear layer in 11 subjects (16 eyes) and inner plexiform layer in 16 subjects (25 eyes). There was subfoveal fluid in both eyes of 6 subjects (15.4%). Mean central foveal thickness of the entire group was 93+/-41microns and 157 +/- 69 microns in the subjects with subfoveal fluid.

Conclusions: : Foveal maturation is not complete at term birth and individual foveal maturation can be documented in the newborn with handheld SDOCT at the bedside. Subclinical pathology can be detected with this imaging modality. These findings may be a variation of newborn infant foveal morphology. The imaging obtained in this study represents the first normative data of the newborn macula by SDOCT.

Keywords: imaging methods (CT, FA, ICG, MRI, OCT, RTA, SLO, ultrasound) • retina • infant vision