Faculty Collaboration Database

Foveal Cone Structure in Patients With Blue Cone Monochromacy. Invest Ophthalmol Vis Sci 2022 Oct 03;63(11):23

Date

10/28/2022

Pubmed ID

36301530

Pubmed Central ID

PMC9624264

DOI

10.1167/iovs.63.11.23

Scopus ID

2-s2.0-85140862245 (requires institutional sign-in at Scopus site)   4 Citations

Abstract

PURPOSE: Blue cone monochromacy (BCM) is a rare inherited cone disorder in which both long- (L-) and middle- (M-) wavelength sensitive cone classes are either impaired or nonfunctional. Assessing genotype-phenotype relationships in BCM can improve our understanding of retinal development in the absence of functional L- and M-cones. Here we examined foveal cone structure in patients with genetically-confirmed BCM, using adaptive optics scanning light ophthalmoscopy (AOSLO).

METHODS: Twenty-three male patients (aged 6-75 years) with genetically-confirmed BCM were recruited for high-resolution imaging. Eight patients had a deletion of the locus control region (LCR), and 15 had a missense mutation-Cys203Arg-affecting the first two genes in the opsin gene array. Foveal cone structure was assessed using confocal and non-confocal split-detection AOSLO across a 300 × 300 µm area, centered on the location of peak cell density.

RESULTS: Only one of eight patients with LCR deletions and 10 of 15 patients with Cys203Arg mutations had analyzable images. Mean total cone density for Cys203Arg patients was 16,664 ± 11,513 cones/mm2 (n = 10), which is, on average, around 40% of normal. Waveguiding cone density was 2073 ± 963 cones/mm2 (n = 9), which was consistent with published histological estimates of S-cone density in the normal eye. The one patient with an LCR deletion had a total cone density of 10,246 cones/mm2 and waveguiding density of 1535 cones/mm2.

CONCLUSIONS: Our results show that BCM patients with LCR deletions and Cys203Arg mutations have a population of non-waveguiding photoreceptors, although the spectral identity and level of function remain unknown.

Author List

Patterson EJ, Kalitzeos A, Kane TM, Singh N, Kreis J, Pennesi ME, Hardcastle AJ, Neitz J, Neitz M, Michaelides M, Carroll J

Author

Joseph J. Carroll PhD Director, Professor in the Ophthalmology and Visual Sciences department at Medical College of Wisconsin

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

Color Vision Defects
Fovea Centralis
Humans
Male
Ophthalmoscopy
Retinal Cone Photoreceptor Cells