Evaluation of focal damage in the retinal pigment epithelium layer in serous retinal pigment epithelium detachment with multi-contrast OCT

Abstract

Purpose : To evaluate focal damage in the retinal pigment epithelium (RPE) layer in serous retinal pigment epithelium detachment (PED) with multi-contrast OCT, which is capable of simultaneous measurement of OCT angiography, polarization-sensitive OCT and standard OCT images.

Methods : We evaluated 37 eyes of 31 subjects with age-related macular degeneration that had serous PED. Focal RPE damage was indicated by hyper-transmission beneath the RPE-Bruch’s membrane band in standard OCT images. For each point of hyper-transmission, two ophthalmologists subjectively classified the presence of change (attenuation or disruption) at the RPE-Bruch's membrane band in standard OCT images: pattern 1; no change, pattern 2; mild change, pattern3; clear change. For automatic detection of RPE melanin with multi-contrast OCT, we developed a virtual contrast value F_RPE, which is computed from multi-contrast images. The cross-sectional F_RPE image shows the distribution of melanin associated with RPE (RPE-melanin). The volumes of PED and intraretinal hyper-reflective foci (HRF) were calculated using standard OCT images, and compared with the existence of focal RPE damage.

Results : A total of 24 points of hyper-transmission beneath the RPE-Bruch’s membrane were detected in 21 (57 %) of 37 eyes in standard OCT images. Among them, number of points in each pattern was 5, 10 and 9 points for pattern 1, 2 and 3, respectively. Consequently, standard OCT images failed to show disruption of the RPE-Bruch’s membrane band at 5 of the 24 (21 %) hyper-transmission points. Conversely, RPE-melanin (F_RPE) cross-sectional images clearly showed melanin defects in the RPE-Bruch’s membrane band at all points. Mean area of focal RPE damage in pattern 1 was significantly smaller than pattern 2 or 3 (P = 0.029 and 0.003, respectively). There was no significant difference in the PED volumes based on the presence or absence of focal damage (P = 0.84). Mean HRF volume was significantly larger for eyes with focal RPE damage than for those without focal RPE damage (P = 0.001).

Conclusions : Multi-contrast OCT is more sensitive than standard OCT for displaying changes at the RPE-Bruch’s membrane band when there are small areas of RPE damage. In serous PED, the development of focal RPE damage is related with HRF.

This abstract was presented at the 2019 ARVO Annual Meeting, held in Vancouver, Canada, April 28 - May 2, 2019.

 

Pattern 1: Focal RPE damage without attenuation at RPE-Bruch’s membrane band.