LAUSR

PURPOSE To quantitatively measure hyperreflective foci (HRF) during the progression of geographic atrophy (GA) secondary to age-related macular degeneration (AMD) using deep learning (DL) and investigate the association with local and global growth of GA. METHODS Eyes with GA were prospectively included. Spectral-domain optical coherence tomography (SD-OCT) and fundus autofluorescence images were acquired every 6 months. A 500-μm wide junctional zone adjacent to the GA border was delineated and HRF were quantified using a validated DL algorithm. HRF concentrations in progressing and non-progressing areas, as well as correlations between HRF quantifications and global and local GA progression were assessed. RESULTS A total of 491 SD-OCT volumes from 87 eyes of 54 patients were assessed with a median follow-up of 28 months. Two-thirds of HRF were localized within a millimeter adjacent to the GA border. HRF concentration was positively correlated with GA progression in unifocal and multifocal GA (all p<.001) and de-novo GA development (p=.037). Local progression speed correlated positively with local increase of HRF (p-value range <.001-.004). Global progression speed, however, did not correlate with HRF concentrations (p>.05). Changes in HRF over time did not have an impact on the growth in GA (p>.05). CONCLUSION Advanced AI methods in high resolution retinal imaging allows to identify, localize and quantify biomarkers such as HRF. Increased HRF concentrations in the junctional zone and future macular atrophy may represent progressive migration and loss of retinal pigment epithelium. AI-based biomarker monitoring may pave the way into the era of individualized risk assessment and objective decision making processes.