Community Based Eye Screenings Using Retinal and OCT-B Combination Imaging in Glaucoma During COVID-19

ABSTRACT

Purpose: Retinal imaging is the gold standard in tele-ophthalmology. Limitations in twodimensional imaging can lead to poor triage or unnecessary clinical referrals, especially during COVID-19. Combined retinal imaging with Optical Coherence Tomography-B scan (OCT-B) in detecting vision threatening diseases (VTDs) such as glaucoma in communitybased screenings adds a third dimension to subject data. Methods: A non-mydriatic Topcon 3D Maestro1 imaging system was deployed in this pilot study to screen 120 subjects (43.3% male, mean age 55.1) in community-based screenings. Measurements of vertical cup-to-disc ratio (VCDR), nerve fiber layer (NFL) thickness and macular and ganglion cell layer (GCL) thickness were collected along with color retinal images by the Maestro1. Visual acuity and intraocular pressures (IOP) were obtained as part of the screening protocol. Four types of OCTs were acquired 78.33% 3D Wide, 13.33% 3D Macula, 5.83% 3D Disc, and 2.51% 5-Line Cross. An on-site certified reader (CR) interpreted results and provided consultation follow-up to a remote ophthalmic subspecialist. Results: Of 222 eyes, OCT-B confirmed follow-up in 86.94%. 88.3% of subjects had referable eye pathology 23.33% to general or specialty eye clinic and 65% to telemedicine. CR glaucoma referral based on OCT-B scan, VCDR and NFL defects was compared to OCT-B referral based on VCDR ≥0.65. Cohen's kappa was 0.546 with 30% disagreement. Compared to CR, OCT-B generated VCDR had a 91.1% specificity and 42.3% sensitivity in detecting glaucoma. VCDR, IOP, NFL, and GCL measurements were significantly correlated with CR glaucoma referral (p<0.05). Only VCDR, NFL, and GCL were significantly correlated with Maestro 1 glaucoma referral (p<0.05). Conclusions: OCT-B images provide valuable added diagnostic information about referrals in glaucoma. Its ability to capture greater depth of information about the eye, such as NFL and GCL measurements, compared to traditional two-dimensional retinal photography, warrants consideration for OCT-B as a replacement for non-mydriatic retinal photography as the gold standard in ophthalmic diagnostics. Further studies can investigate the utility trend analysis of OCT-B in predicting VTD's progression over time.