**1. Introduction**

Macular pigment (MP) plays an important role in visual function [1] and in the protection of the retina against oxidative damage [2,3]. It is located in the inner layers of the retina [4] and composed of three carotenoids. Two of them are exclusively from dietary origin (lutein and zeaxanthin) while the third one (meso-zeaxanthin) is synthetized from lutein. The highest MP concentration is located in the Henle's fiber layer of the fovea and rapidly decreases to be undetectable outside the macula. In the literature, three MP patterns have been reported: the no-ring profile, ring-like profile, and an intermediate profile [5–8].

**Citation:** Arnould, L.; Seydou, A.; Binquet, C.; Gabrielle, P.-H.; Chamard, C.; Bretillon, L.; Bron, A.M.; Acar, N.; Creuzot-Garcher, C. Macular Pigment and Open-Angle Glaucoma in the Elderly: The Montrachet Population-Based Study. *J. Clin. Med.* **2022**, *11*, 1830. https:// doi.org/10.3390/jcm11071830

Academic Editors: Michele Lanza, Miriam Kolko and Barbara Cvenkel

Received: 7 March 2022 Accepted: 23 March 2022 Published: 25 March 2022

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**Copyright:** © 2022 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https:// creativecommons.org/licenses/by/ 4.0/).

MP and oral dietary carotenoid supplementation have been extensively studied in macular disorders, especially in age-related macular degeneration (AMD). Numerous studies suggested the role of carotenoid in the prevention of AMD [9,10].

Glaucoma is the most common optic neuropathy in adulthood, leading to irreversible damages of the structure and function of the optic nerve [11]. It is defined as a multifactorial progressive optic neuropathy with a typically acquired loss of optic nerve fibers (death of the retinal ganglion cell axons) [12,13]. Primary open-angle glaucoma (POAG) is the most common form of this disease [14]. In 2020, it was estimated that nearly 52 million people are affected by POAG worldwide and that this number would increase to 79 million by 2040 [15].

To date, the relationship between MPOD and POAG is conflicting and the association between neurodegenerative disease and MP is less straightforward. MP and glaucoma could be linked based on two major hypotheses: microvascular and oxidative stress processes [16]. According to several research teams, MP could absorb vision blue light, hence decreasing light energy in the inner retina and photo-oxidative injury [17]. Some studies found that lower densities of MP were found in glaucoma patients, [18] whereas other studies could not support this assumption [19]. The primary objective of this study was to compare MPOD between eyes with POAG and control eyes in an elderly population. The secondary objective was to compare the MP spatial distribution between both groups.
