Optical coherence tomography (OCT) is a non-invasive, rapid optical medical imaging modality and has become a hot topic in biomedical research. In recent years, several functional OCTs have emerged, including Doppler OCT, polarization-sensitive OCT, spectroscopic OCT, and optical coherence tomographic elastography, etc. These newer advances in functional OCT broaden the potential clinical application of OCT by providing novel ways to observe and understand tissue activity that cannot be accomplished by other current imaging methodologies.
ObjectiveTo observe the macular morphological development and thickness of retinal layers in infants. MethodsFifty-eight infants (86 eyes) were randomly selected from neonatal intensive care unit. They were divided into 4 groups according to the corrected gestational age, including <32 weeks group (10 cases, 14 eyes), 33 to 36 weeks group (26 cases, 39 eyes), 37 to 41 weeks group (12 patients, 18 eyes) and ≥42 weeks group (10 cases,15 eyes). Twelve health adults (22 eyes) were randomly selected as adult group. All infants and adults underwent a portable optical coherence tomography (OCT) examination, focus on the macular morphology. The thickness of 9 retinal layers at fovea and parafovea (750 μm, 1500 μm from central fovea) were measured, including retinal neurepithelium layer, the inner retina, the outer retina, nerve fiber layer, ganglion cell layer, inner plexiform layer, inner nuclear layer, outer plexiform layer and inner nuclear layer. The correlation between retinal thickness and corrected gestational age was analyzed. ResultsMacular fovea was shallow in early infancy, and then form a mature macular fovea finally with corrected gestational age. The outer retina structure was more mature than the inner retina of infants. With the increase of the corrected gestational age, the following structures gradually developed including the outer limiting membrane (OLM), the junction of inner and outer segment of photoreceptor (IS/OS), the outer segment of photoreceptor/retinal pigment epithelium layer (OS/RPE). The earliest corrected gestational age to detect the OLM, IS/OS, OS/RPE was 32+6, 35, 47+6 weeks respectively. The RPE and choroid layer became thicker gradually. There were no statistical differences between infants group and adults group (P>0.01) for the following thickness measurements, including inner retina at 750 μm parafovea, nerve fiber layer at 1500 μm parafovea, ganglion cell layer at central fovea and parafovea (750 μm, 1500 μm). The thickness of other retinal layers was different between different sites, between different corrected gestational ages, and between infants and adults groups (P<0.01). Correlation analysis found that, except of retinal ganglion cell layer, the thickness of other retinal layers was correlated with the corrected gestational age (P<0.05). ConclusionsMacular fovea is shallow in early infancy, and then form a mature macular fovea finally with corrected gestational age. At infant's early stage, the outer retina of macular is gradually thickening, of which the most obvious variation are the inner nuclear layer and outer nuclear layer. But the development speed of all layers is inconformity.