Choroid development and feasibility of choroidal imaging in the preterm and term infants utilizing SD-OCT

To determine whether choroidal imaging is feasible in preterm and term infants using an 840-nm portable spectral domain optical coherence tomography (SD-OCT) system without the use of enhanced-depth imaging techniques and to assess choroidal development by comparing choroidal thickness of preterm infants, term infants, and adults.

SD-OCT images were obtained from 86 preterm infants, 59 term infants, and nine adults using a portable SD-OCT system plus nine adults using a tabletop system. An unprocessed image across the macula from one randomly selected eye of each participant was selected for determination of whether the choroidal-scleral junction (CSJ) could be visualized and for measurement of choroidal thickness.

Subfoveal CSJ was visualized in 96% of young-preterm infants (imaged from 30-36 weeks postmenstrual age [PMA]); 78% of term-aged preterm infants (imaged from 37-42 weeks PMA); 49% of term infants; and 39% of adult subjects. Racial pigmentation did not affect CSJ visibility in young-preterm infants (P = 0.57). Subfoveal choroidal thickness (SFCT) in young-preterm infants, term-aged preterm infants, term infants, and adults was 176 ± 53 μm, 289 ± 92 μm, 329 ± 66 μm, and 258 ± 66 μm, respectively, and these were all statistically significantly different from one another except term-aged preterms to adults.

Infant choroid can be imaged with a portable SD-OCT system without enhanced depth imaging. Melanin in the RPE and choroid does not hinder outer choroidal imaging in young-preterm infants without advanced retinopathy of prematurity (ROP). In preterm infants, choroidal thickness increased with age but was thinner when compared to term infants suggesting delayed development due to ROP.