Open AccessAssessing Interocular Symmetry of the Foveal Cone Mosaic
Author(s) -
Jenna Cava,
Mitchell Allphin,
Rebecca Mastey,
Mina Gaffney,
Rachel E Linderman,
Robert F. Cooper,
Joseph Carroll
Publication year - 2020
Publication title -
investigative ophthalmology and visual science
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.935
H-Index - 218
eISSN - 1552-5783
pISSN - 0146-0404
DOI - 10.1167/iovs.61.14.23
Subject(s) - foveal , roundness (object) , cone (formal languages) , normal vision , optics , mathematics , anatomy , fovea centralis , physics , geometry , ophthalmology , optometry , medicine , retinal , algorithm
Purpose To test the hypothesis that foveal cone topography is symmetrical between contralateral eyes. Methods We used adaptive optics scanning light ophthalmoscopy to acquire images of the foveal cone mosaic in each eye of 58 subjects with normal vision (35 female, 23 male). Cones were semiautomatically identified over a 300 × 300-µm foveal area. From these cone coordinates, maps of cone density were derived, and we extracted estimates of peak cone density from each map. Mosaic regularity was assessed using Voronoi cell area regularity (VCAR). Average roundness and average area of the 70%, 75%, 80%, 85%, and 90% of peak density isodensity contours were evaluated. Results The average peak cone density for right eyes was 180,286 cones/mm 2 ( n = 49) and for left eyes was 182,397 cones/mm 2 ( n = 45), with a mean absolute difference of 6363 cones/mm 2 ( n = 43). Peak density, cone spacing, VCAR, and average area within the isodensity contours of fellow eyes were not significantly different ( P = 0.60, P = 0.83, P = 0.30, and P = 0.39, respectively). However, the average roundness of the isodensity contours was 2% more circular in the right eyes than in the left eyes ( P = 0.02). Conclusions There is interocular symmetry of peak foveal cone density, mosaic regularity, and area encompassing the most densely packed cells in subjects with normal vision. The origin and significance of the observed interocular difference in average roundness of the isodensity contours are unclear.