Alterations of the Ganglion Cell Complex in Age-Related Macular Degeneration: An Amish Eye Study Analysis

Swetha Bindu Velaga; Ahmed Roshdy Alagorie; Mehdi Emamverdi; Maryam Ashrafkhorasani; Abbas Habibi; Muneeswar Gupta Nittala; Gagan Sing; Jonathan Haines; Margaret A Pericak-Vance; Dwight Stambolian; Srinivas R Sadda

doi:10.1016/j.ajo.2024.04.024

Alterations of the Ganglion Cell Complex in Age-Related Macular Degeneration: An Amish Eye Study Analysis

Am J Ophthalmol. 2024 Apr 26:265:80-87. doi: 10.1016/j.ajo.2024.04.024. Online ahead of print.

Affiliations

¹ From the Doheny Eye Institute (S.B.V., A.R.A., M.E., M.A., A.H., M.G.N., G.S., S.R.S.), University of California-Los Angeles, Los Angeles, California, USA; Department of Ophthalmology (S.B.V., A.R.A., M.E., M.A., A.H., M.G.N., S.R.S.), David Geffen School of Medicine at UCLA, Los Angeles, CA, USA.
² From the Doheny Eye Institute (S.B.V., A.R.A., M.E., M.A., A.H., M.G.N., G.S., S.R.S.), University of California-Los Angeles, Los Angeles, California, USA; Department of Ophthalmology (S.B.V., A.R.A., M.E., M.A., A.H., M.G.N., S.R.S.), David Geffen School of Medicine at UCLA, Los Angeles, CA, USA; Department of Ophthalmology (A.R.A.), Faculty of Medicine, Tanta University, Tanta, Egypt.
³ Department of Population & Quantitative Health Sciences (J.H.), Case Western Reserve University, Cleveland, Ohio, USA; Institute for Computational Biology (J.H.), Case Western Reserve University, Cleveland, Ohio, USA.
⁴ John P. Hussman Institute for Human Genomics (M.A.P.-V), University of Miami Miller School of Medicine, Miami, Florida, USA.
⁵ Department of Ophthalmology (D.S.), University of Pennsylvania, Perelman School of Medicine, Philadelphia, Pennsylvania, USA.
⁶ From the Doheny Eye Institute (S.B.V., A.R.A., M.E., M.A., A.H., M.G.N., G.S., S.R.S.), University of California-Los Angeles, Los Angeles, California, USA. Electronic address: SSadda@doheny.org.

PMID: 38677638
DOI: 10.1016/j.ajo.2024.04.024

Abstract

Purpose: To compare the ganglion cell complex (GCC) thickness in eyes with age-related macular degeneration (AMD) vs healthy controls in an elderly Amish population.

Design: Prospective cross-sectional study.

Methods: This is a post hoc analysis of the family-based prospective study of Amish subjects. Study subjects underwent imaging with the Cirrus HD-OCT (Carl Zeiss Meditec Inc) using a macular cube protocol of 512 × 128 scans (128 horizontal B-scans, each comprising 512 A-scans) over a 6 mm × 6 mm region centered on the fovea. The ganglion cell analysis algorithm calculated the GCC thickness by segmenting the outer boundaries of the retinal nerve fiber layer (RNFL) and inner plexiform layer (IPL) in all B-scans of the volume, with the region between these boundaries representing the combined thickness of the ganglion cell layer (GCL) and the IPL. A number of parameters were used to evaluate the GCC thickness: the average GCC thickness, minimum (lowest GCC thickness at a single meridian crossing the elliptical annulus), and sectoral (within each of 6 sectoral areas: superior, superotemporal, superonasal, inferior, inferonasal, and inferotemporal). The stage of AMD was graded on color fundus photographs in accordance with the Beckman Initiative for Macular Research classification system.

Results: Of 1339 subjects enrolled in the Amish eye study, a total of 1294 eyes of 1294 subjects had all required imaging studies of sufficient quality and were included in the final analysis. Of these, 798 (62%) were female. Following age adjustment, the average GCC thickness was significantly (P < .001) thinner in AMD subjects (73.71 ± SD; 13.77 µm) compared to normals (77.97 ± 10.42 µm). An independent t test showed that the early AMD (75.03 ± 12.45 µm) and late AMD (61.64 ± 21.18 µm) groups (among which eyes with geographic atrophy [GA] had the lowest thickness, of 58.10 ± 20.27 µm) had a statistically significant lower GCC thickness compared to eyes without AMD. There was no significant differences in average GCC thickness between early AMD and intermediate AMD (76.36 ± 9.25 µm) eyes.

Conclusions: The GCC thickness in AMD eyes is reduced compared to normal eyes; however, the relationship is complex, with the greatest reduction in late AMD eyes (particularly eyes with GA) but no difference between early and intermediate AMD eyes.