Auto-Processed Retinal Vessel Shadow View Images From Bedside Optical Coherence Tomography to Evaluate Plus Disease in Retinopathy of Prematurity

Abstract

To describe the creation of en face retinal vessel shadow view (RVSV) optical coherence tomography (OCT) images and assess the feasibility of using these for evaluating vascular disease in preterm infants at risk for retinopathy of prematurity (ROP). Methods: In this exploratory study, we selected images from eyes with a range of ROP vascular disease, prospectively acquired from preterm infants using an investigational, noncontact, handheld, bedside swept-source OCT. We autosegmented OCT volumes using custom infant-specific software, extracted RVSV-OCT images from volumetric data bracketed around the retinal pigment epithelium, and automontaged the resulting RVSV-OCT images. Three masked ophthalmologists graded the RVSV-OCT montages as plus, pre-plus, or neither and ranked them by relative vascular disease severity. Results: We selected images from 17 imaging sessions (7 plus, 4 pre-plus, 6 neither on clinical examination). On review, 15/17 (88%) RVSV-OCT montages were gradable for plus, pre-plus, or neither and all 17 montages were rankable for relative severity. Intergrader agreement for plus, pre-plus, or neither grading was good (κ, 0.67; 95% confidence interval, 0.42-0.86) and for relative severity ranking was excellent (intraclass correlation coefficient, 0.98; 95% confidence interval, 0.96-0.99). Conclusions: Our novel automatic processing method can create RVSV-OCT montages optimized for retinal vessel visualization for ROP screening. Although our data support the feasibility of using RVSV-OCT montages for ranking relative vascular disease severity, there is room for improved OCT image capture and processing methods in preterm infants screened for ROP. Translational Relevance: Creation and grading of RVSV-OCT images could eventually be integrated into an alternative method for ROP screening.

Ocular Pigmentation Impact on Retinal Versus Choroidal Optical Coherence Tomography Imaging in Preterm Infants

“…Third, because the quality of en face imaging changed with pixel density midway through the study, we analyzed cross-sectional OCT scans and not the quality of en face posterior pole retinal vessel maps. Thus, although the demonstrated visibility of retinal layers, particularly the RPE, should be sufficient for the generation of high-quality retinal vessel maps, 20 we could not directly assess the impact of fundus pigmentation on en face retinal vessel map quality.…”

Ocular Pigmentation Impact on Retinal Versus Choroidal Optical Coherence Tomography Imaging in Preterm Infants

“…Third, because the quality of en face imaging changed with pixel density midway through the study, we analyzed cross-sectional OCT scans and not the quality of en face posterior pole retinal vessel maps. Thus, although the demonstrated visibility of retinal layers, particularly the RPE, should be sufficient for the generation of high-quality retinal vessel maps, 20 we could not directly assess the impact of fundus pigmentation on en face retinal vessel map quality.…”

Integrated Visualization Highlighting Retinal Changes in Retinopathy of Prematurity From 3-Dimensional Optical Coherence Tomography Data

“…As stated in that study, the primary goal of imaging was the macula, which limited capture of the arcades. Since then, we have modified OCT speed, the imaging protocol, and image processing with the goal of acquiring scans that provide sufficient information for the diagnosis of plus disease . The visualization reported here, by providing integrated data on the relative location of abnormalities of retinal tissue, retinal vasculature, and extraretinal neovascularization, improves researchers’ understanding of pathology based on OCT morphology and reveals indicators and associations that may be helpful in categorizing plus disease …”

“…For 3-D visualization, we incorporated en face OCT images extracted from a narrow axial window bracketed around the retinal pigment epithelium (retinal vessel shadow view [RVSV-OCT]) and thickness maps generated using software optimized for automatic segmentation (DOCTRAP version 66.2). We extracted the internal limiting membrane and Bruch membrane segmentation from OCT volumes.…”

Preterm Infant Stress During Handheld Optical Coherence Tomography vs Binocular Indirect Ophthalmoscopy Examination for Retinopathy of Prematurity

“…To monitor these stress events, we relied on preset alarms for each infant, as opposed to clinically defined bradycardia (<80 bpm), tachycardia (>200 bpm), and oxygen desaturation (<80%) . While OCT images have not been shown to be equivalent to BIO for ROP determination, this has been the focus of multiple studies demonstrating the future potential . Reduction in early-life stress might be possible in the future if OCT imaging proved comparable with BIO for screening.…”

Ocular Pigmentation Impact on Retinal Versus Choroidal Optical Coherence Tomography Imaging in Preterm Infants

“…Third, because the quality of en face imaging changed with pixel density midway through the study, we analyzed cross-sectional OCT scans and not the quality of en face posterior pole retinal vessel maps. Thus, although the demonstrated visibility of retinal layers, particularly the RPE, should be sufficient for the generation of high-quality retinal vessel maps, 20 we could not directly assess the impact of fundus pigmentation on en face retinal vessel map quality.…”

Integrated Visualization Highlighting Retinal Changes in Retinopathy of Prematurity From 3-Dimensional Optical Coherence Tomography Data

“…As stated in that study, the primary goal of imaging was the macula, which limited capture of the arcades. Since then, we have modified OCT speed, the imaging protocol, and image processing with the goal of acquiring scans that provide sufficient information for the diagnosis of plus disease . The visualization reported here, by providing integrated data on the relative location of abnormalities of retinal tissue, retinal vasculature, and extraretinal neovascularization, improves researchers’ understanding of pathology based on OCT morphology and reveals indicators and associations that may be helpful in categorizing plus disease …”

“…For 3-D visualization, we incorporated en face OCT images extracted from a narrow axial window bracketed around the retinal pigment epithelium (retinal vessel shadow view [RVSV-OCT]) and thickness maps generated using software optimized for automatic segmentation (DOCTRAP version 66.2). We extracted the internal limiting membrane and Bruch membrane segmentation from OCT volumes.…”

Preterm Infant Stress During Handheld Optical Coherence Tomography vs Binocular Indirect Ophthalmoscopy Examination for Retinopathy of Prematurity

“…To monitor these stress events, we relied on preset alarms for each infant, as opposed to clinically defined bradycardia (<80 bpm), tachycardia (>200 bpm), and oxygen desaturation (<80%) . While OCT images have not been shown to be equivalent to BIO for ROP determination, this has been the focus of multiple studies demonstrating the future potential . Reduction in early-life stress might be possible in the future if OCT imaging proved comparable with BIO for screening.…”

Ocular Pigmentation Impact on Retinal Versus Choroidal Optical Coherence Tomography Imaging in Preterm Infants

“…Third, because the quality of en face imaging changed with pixel density midway through the study, we analyzed cross-sectional OCT scans and not the quality of en face posterior pole retinal vessel maps. Thus, although the demonstrated visibility of retinal layers, particularly the RPE, should be sufficient for the generation of high-quality retinal vessel maps, 20 we could not directly assess the impact of fundus pigmentation on en face retinal vessel map quality.…”

Integrated Visualization Highlighting Retinal Changes in Retinopathy of Prematurity From 3-Dimensional Optical Coherence Tomography Data

“…As stated in that study, the primary goal of imaging was the macula, which limited capture of the arcades. Since then, we have modified OCT speed, the imaging protocol, and image processing with the goal of acquiring scans that provide sufficient information for the diagnosis of plus disease . The visualization reported here, by providing integrated data on the relative location of abnormalities of retinal tissue, retinal vasculature, and extraretinal neovascularization, improves researchers’ understanding of pathology based on OCT morphology and reveals indicators and associations that may be helpful in categorizing plus disease …”

“…For 3-D visualization, we incorporated en face OCT images extracted from a narrow axial window bracketed around the retinal pigment epithelium (retinal vessel shadow view [RVSV-OCT]) and thickness maps generated using software optimized for automatic segmentation (DOCTRAP version 66.2). We extracted the internal limiting membrane and Bruch membrane segmentation from OCT volumes.…”

Preterm Infant Stress During Handheld Optical Coherence Tomography vs Binocular Indirect Ophthalmoscopy Examination for Retinopathy of Prematurity

“…To monitor these stress events, we relied on preset alarms for each infant, as opposed to clinically defined bradycardia (<80 bpm), tachycardia (>200 bpm), and oxygen desaturation (<80%) . While OCT images have not been shown to be equivalent to BIO for ROP determination, this has been the focus of multiple studies demonstrating the future potential . Reduction in early-life stress might be possible in the future if OCT imaging proved comparable with BIO for screening.…”