Ultrahigh Resolution SD-OCT Can Differentiate AMD Pathology From Normal Aging

Among individuals with older age, the appearance of a split/hypo-reflective band in the sub-retinal pigment epithelium (RPE) basal lamina (BL) and Bruch’s membrane (BrM) complex (RPE-BL-BrM) may be a marker of age-related macular degeneration (AMD), according to research published in Ophthalmology Science. Ultrahigh resolution spectral domain-optical coherence tomography (UHR-SD-OCT) can be used to detect this marker, discriminating AMD pathology from normal aging, the report shows. 

Researchers included individuals with dry AMD (n=39; eyes, 53; mean age, 77.5 years; 51.3% women) and control group participants (n=39; eyes, 63; mean age, 53.6 years; 59% women) from the New England Eye Center retina clinic in the cross-sectional, observational study. All participants underwent UHR-SD-OCT and 3 trained readers labeled outer retina morphological features, which included a hyporeflective split within the RPE-BL-BrM complex. The team also measured the thickness of this RPE-BL-BrM split/hyporeflective band.

UHR-SD-OCT scans from 1 control group participant with younger age (age, 29 years),  1 control group participant with older age (age, 57 years), and 1 patient with older age and early AMD (age, 73 years) were used to represent younger age without AMD, older age without AMD, and older age with AMD.

All hyper-reflective outer retinal bands were resolved with clear boundaries in the patient with younger age The participant with older age without AMD demonstrated a thick external limiting membrane with an irregular appearance. The hypo-reflective band had been reduced, was not clearly resolved below the fovea, and patchy on the temporal side. The patient with early AMD had a hypo-reflective band that was only present in 1 patchy region on the temporal side, as well as a 1.2 mm-wide segment bordering the optic nerve head. These observations were representative of the larger cohort, according to the report. 

“This study demonstrates that UHR SD-OCT is a promising modality that can reveal outer retinal alterations associated with normal aging and early AMD pathology,” according to the researchers. “Ultrahigh resolution OCT promises to enable new imaging markers for AMD diagnosis, monitoring progression and response to therapy, as well as to enable investigations of AMD pathogenesis in vivo and accelerate future therapeutic trials.”

Study limitations included a small sample size of patients with early or late AMD and a lack of clinicopathologic comparisons.

Disclosure: This research was supported by Topcon Medical Systems. Some study authors declared affiliations with the biotech, pharmaceutical, and/or device companies. Please see the original reference for a full list of authors’ disclosures.