Abstract
Purpose :
Interpretation of choroidal neovascularization (CNV) lesions can be challenging when the quality of the B-scan is not adequate. Instead the clinician may prefer the enface flow image; which is highly dependent on the segmentation of the layers and can be time consuming. In this study we demonstrate the advantage of high quality structural B-scans with OCTA flow overlaid in the interpretation and visualization of CNV.
Methods :
Five eyes with CNV were imaged on a PLEX® Elite 9000 swept-source OCT (ZEISS, Dublin, CA) with modified software, using a new scan pattern consisting of 51 high resolution structural and high-resolution flow B-scans; each generated from averaging 20 angio B-scans consisting of 512 A-scans over a 6 mm segment. Appropriate balance of scan resolution and scan time lead to higher density of B-scans with 20 um spacing in the central 0.5 mm central and 210 um elsewhere. Projection-artifact removal was applied to the flow data followed by segmentation of the retinal pigment epithelium (RPE) layer to differentiate flow below and above the RPE.
Results :
Figure 1 shows an example of a high resolution structural and flow B-scan for an eye with CNV . Higher concentration of flow along with proper projection artifact removal clearly reveals the presence of neovascularization above the RPE and below the Bruch ‘s membrane as shown by the arrow. Figure 2 shows the same B-scan from an Angio 6x6 mm scan along with the corresponding flow enface image to confirm the presence of the CNV. For all 5 eyes with CNV, the grader found it was easier to identify the lesion from the high resolution OCTA B-scans.
Conclusions :
High definition OCTA B-scans improves the visualization of CNV and could be valuable for the interpretation of the lesions.
This abstract was presented at the 2019 ARVO Annual Meeting, held in Vancouver, Canada, April 28 - May 2, 2019.