Three-Dimensional Assessment of Vascular and Perivascular Characteristics in Subjects with Retinopathy of Prematurity

Abstract

To study vascular features detected with spectral domain optical coherence tomography (SD-OCT) in subjects undergoing retinopathy of prematurity (ROP) screening. Cross-sectional study. Fifty-seven premature neonates, 10 with plus disease in at least 1 eye and 47without plus disease. Bedside noncontact SD-OCT imaging was performed after obtaining parental consent on 97 consecutive infants between January 2009 and September 2012. Fifty-seven subjects (31-49 weeks' post-menstrual age) who had an SD-OCT scan in at least 1 eye showing the edge of the optic nerve and at least 1 major retinal vascular arcade were included. One eye per subject was randomly selected for analysis. Two masked graders evaluated scans for (1) retinal vessel elevation, (2) scalloped retinal layers, (3) hyporeflective vessels, and (4) retinal spaces. To coalesce the weight of these features, a Vascular Abnormality Score by OCT (VASO) was created. For quantitative assessment of vessel elevation, retinal surface maps were created. Prevalence of SD-OCT vascular abnormalities, the VASO, intergrader agreement, and presence of elevation on surface maps. From among 67 SD-OCT characteristics that were recorded, the most common characteristics found were vessel elevation (44%), hyporeflective vessels (40%), scalloped layers (22%), and retinal spaces (11%). Features significantly associated with plus disease were vessel elevation (P= 0.01), hyporeflective vessels (P= 0.04), and scalloped retinal layers (P= 0.006). Intragrader agreement was between 74% and 90% for all features. The VASO was significantly higher in subjects with plus disease (P= 0.0013). On 3-dimensional SD-OCT volumes, eyes with plus disease had greater retinal surface elevation that more often matched en face retinal vascular patterns. We present a novel 3-dimensional analysis of vascular and perivascular abnormalities identified in SD-OCT images of eyes with ROP. The SD-OCT characteristics that are more common in eyes with plus disease provide the first invivo demonstration of the effects of vascular dilation and tortuosity on perivascular tissue. The VASO and surface maps also delineate the severity of vascular pathology in plus disease. Further studies evaluating these findings in eyes with pre-plus versus normal posterior pole vessels may determine the usefulness of SD-OCT in the early detection of vascular abnormalities in ROP.