Handheld swept-source optical coherence tomography with angiography in awake premature neonates

Abstract

Background: Retinopathy of prematurity (ROP) can lead to retinal detachment and severe vision loss and is a common cause of childhood blindness. Optical coherence tomography angiography (OCTA) is a noninvasive imaging modality that can be used to detect potential abnormalities in the microvasculature in this population. The objective of this study is to assess the feasibility of a newly developed handheld swept source OCT (SS-OCT) device to successfully acquire structural vitreoretinal and retinal microvascular images in awake premature infants.Methods: OCT and OCTA images were acquired at the time of routine ROP examinations from awake, unsedated preterm infants in the Neonatal Intensive Care Unit using a clinical research prototype handheld probe integrated with an SS-OCT system working at 1,060 nm wavelength and an imaging speed of 200,000 A-scans per second (200 kHz), enabling volume OCT and OCTA scans. Each volume was acquired with approximately 36˚ field of view (~6.3×6.3 mm in infants) in 4.8 s. Quality of acquired OCT and OCTA volume images, microvascular information, and vitreoretinal features were determined by 3-masked grader consensus.Results: Twelve infants (5 females, mean gestational age 28.3 weeks, median birth weight 901 g, stages 0 to 3 ROP) underwent a total of 73 individual eye imaging sessions. High-quality OCT images of the fovea and the optic nerve were present in 69/73 (94.5%) and 56/73 (76.7%) scans, respectively. Vitreous bands were observed in 10/73 (13.7%); punctate hyperreflective vitreous opacities in 47/73 (64.4%); epiretinal membrane (ERM) in 6/73 (8.2%); and cystoid macular edema (CME) in 12/73 (16.4%) scans. Mild vessel elevation was noted in 3/73 (4.1%) images, and severe vessel elevation in 4/73 (5.5%) scans. OCTA images obtained in 8 awake infants revealed good quality images of the foveal microvasculature in 11/19 (58%) eye imaging sessions for 6/8 (75%) infants; and peripapillary microvasculature in 14/19 (74%) eye imaging sessions for 5/8 (63%) infants. Conclusions:The SS-OCTA handheld device can capture important vitreoretinal characteristics such as peripapillary and foveal microvasculature, as well as hyperreflective punctate vitreous opacities and tractional vitreous bands, which may predict ROP severity. These images were captured in awake, premature infants without the use of direct ocular contact, an eyelid speculum, or sedation.

Choroidal Thickness by Handheld Swept-Source Optical Coherence Tomography in Term Newborns

“…This provides a measured axial resolution of approximately 6 μm in tissue and a calculated lateral resolution on the retina of approximately 16 μm (for a typically 7 × 7-mm, or 40°, field of view at 400 B-scans × 400 Ascans/B-scan and with four repeats). 18,19 Participating infants underwent a single awake imaging session within the first 72 hours of life. Imaging was performed as previously described.…”

“…Imaging was performed as previously described. 18,19 Briefly, infants were dilated with 1% phenylephrine hydrochloride and 0.2% cyclopentolate (Cyclomydril; Alcon Laboratories, Fort Worth, TX) at least 40 minutes prior to the examination. One of the authors (ATL), who was experienced in handheld OCT, imaged all infants in the supine position without an eyelid speculum or ocular contact.…”

Quantitative Handheld Swept-Source Optical Coherence Tomography Angiography in Awake Preterm and Full-Term Infants

“…Eight premature infants (16 eyes) and 12 full-term infants (24 eyes) were enrolled in this study. Among premature infants, five infants included in the previous studies 22 , 27 were also included in this study. The study was approved by the institutional review board of Seattle Children's Hospital and the University of Washington (Seattle, Washington), which also conformed to the tenets of the Declaration of Helsinki and the Health Insurance Portability and Accountability Act.…”

“…The capability of this system was demonstrated on healthy adults and nonsedated preterm and full-term infants with high-quality four-layer OCTA (superficial retina, deep retina, choriocapillaris, and deep choroid). 22 , 27 …”

Retinal blood flow in critical illness and systemic disease: a review

“…A prototype handheld SS-OCTA device was used to capture high-quality vitreoretinal images in awake premature neonates at risk for retinopathy of prematurity, with greater imaging speed and detail compared with currently available handheld SD-OCT devices [ 121 ].…”