Faculty Collaboration Database

A 2-Year Longitudinal Study of Normal Cone Photoreceptor Density. Invest Ophthalmol Vis Sci 2019 Apr 01;60(5):1420-1430

Date

04/04/2019

Pubmed ID

30943290

Pubmed Central ID

PMC6736277

DOI

10.1167/iovs.18-25904

Scopus ID

2-s2.0-85064239192 (requires institutional sign-in at Scopus site)   12 Citations

Abstract

PURPOSE: Despite the potential for adaptive optics scanning light ophthalmoscopy (AOSLO) to quantify retinal disease progression at the cellular level, there remain few longitudinal studies investigating changes in cone density as a measure of disease progression. Here, we undertook a prospective, longitudinal study to investigate the variability of cone density measurements in normal subjects during a 2-year period.

METHODS: Fourteen eyes of nine subjects with no known ocular pathology were imaged both at a baseline and a 2-year follow-up visit by using confocal AOSLO at five retinal locations. Two-year affine-registered images were created to minimize the effects of intraframe distortions. Regions of interest were cropped from baseline, 2-year manually aligned, and 2-year affine-registered images. Cones were identified (graded masked) and cone density was extracted.

RESULTS: Mean baseline cone density (cones/mm2) was 87,300, 62,200, 45,500, 28,700, and 18,200 at 190, 350, 500, 900, and 1500 μm, respectively. The mean difference (± standard deviation [SD]) in cone density from baseline to 2-year affine-registered images was 1400 (1700), 100 (1800), 300 (800), 400 (800), and 1000 (2400) cones/mm2 at the same locations. The mean difference in cone density during the 2-year period was lower for affine-registered images than manually aligned images.

CONCLUSIONS: There was no meaningful change in normal cone density during a 2-year period. Intervisit variability in cone density measurements decreased when intraframe distortions between time points were minimized. This variability must be considered when planning prospective longitudinal clinical trials using changes in cone density as an outcome measure for assessing retinal disease progression.

Author List

Jackson K, Vergilio GK, Cooper RF, Ying GS, Morgan JIW

Author

Robert F. Cooper Ph.D Assistant Professor in the Biomedical Engineering department at Marquette University

MESH terms used to index this publication - Major topics in bold

Adult
Axial Length, Eye
Diagnostic Techniques, Ophthalmological
Female
Humans
Longitudinal Studies
Male
Middle Aged
Ophthalmoscopy
Prospective Studies
Retinal Cone Photoreceptor Cells
Retinal Diseases
Visual Acuity
Young Adult