Abstract
Purpose :
Novai’s detection of apoptosing retinal cells (DARC) technology allows in vivo localisation of retinal cell death (DARC ‘spots’). Stratification of DARC spots may reveal distinct mechanisms of disease. Here, we hypothesised that eyes contain multiple populations of DARC spots, and that abnormal expression of these populations is indicative of disease.
Methods :
DARC NIRAF retinal imaging was conducted in healthy adults (N=36, mean age=45.97, SD=16.81) and in patients with glaucoma (N=20, mean age=61.74, SD=13.11) or multiple sclerosis (MS) optic neuritis (N=12, mean age=44.47, SD=10.82). For each DARC spot, hysteresis thresholding was applied to identify perimeters from which a set of morphometrics were extracted (e.g., spot area, eccentricity etc). Data-driven hierarchical clustering of the morphometrics generated distinct populations of DARC spots that were then compared between the healthy and patient groups with a two-way chi-square test.
Results :
Hierarchical agglomerative clustering of DARC spot morphometry (Figure 1a) indicated 3 distinct DARC spot types (C0: Small regular, C1: Irregular, C2: Large regular – Figure 1b). The most common DARC spot type in each eye (Figure 1c) significantly differed between the groups (two-way chi2: 13.312, p=0.038).
Conclusions :
This investigation presents evidence indicating that distinct types of DARC spots can be observed in vivo. Critically, an increased proportion of irregularly shaped DARC spots was associated with Glaucoma and MS. While this is suggestive of distinct cellular processes, we are conducting further preclinical and histological work to confirm the validity of these in vivo findings.
This abstract was presented at the 2023 ARVO Annual Meeting, held in New Orleans, LA, April 23-27, 2023.