Comparison Between Different Segmentation Strategies for the Choriocapillaris Using Optical Coherence Tomography Angiography.

BACKGROUND AND OBJECTIVE

To assess the relationship between retinal pigment epithelium (RPE) and RPE fit-based segmentations of the choriocapillaris (CC) and its expected anatomic location.

PATIENTS AND METHODS

Consecutive healthy participants' eyes were imaged with optical coherence tomography angiography (PLEX Elite) with 3 × 3-mm and 6 × 6-mm scan. Ground-truth images were generated using 16-μm-thick slabs starting from 4 μm below the automatically segmented Bruch's membrane (BM) band. A series of slabs positioned below the RPE band and RPE fit were also generated, and CC flow deficit percentage was compared with the ground-truth segmentation.

RESULTS

Twenty-six eyes of 26 participants were analyzed. For both scans, the 21 to 37-μm slab offset from the RPE band most closely matched the BM-based ground-truth slab with mean differences of 0.78% and 0.36%.

CONCLUSION

The CC flow deficit percentage from the RPE band correlated strongly with BM-based CC slabs, with the closest approximation observed with slab offset 21 to 37 μm from the RPE band centerline.