Comparison of Macular Pigment Optical Density in Glaucoma Patients and Healthy Subjects - A Prospective Diagnostic Study

Macular Pigment Optical Density as a Measurable Modifiable Clinical Biomarker

BACKGROUND

Carotenoids are present throughout retina and body its dense deposition leads to an identifiable yellow spot in the macula. Macular pigment optical density (MPOD) measured in the macula is vital to macular well-being and high-resolution visual acuity. MPOD has also been associated with various health and disease states. We sought to review the literature on this topic and summarize MPODs role as a measurable modifiable clinical biomarker, particularly as a measure of the eye's antioxidant capacity in the context of oxidative damage and retinal ischemia.

METHODS

A literature review collated the articles relevant to MPOD, carotenoid intake or supplementation, and their influence on various health and disease states.

RESULTS

Literature reveals that MPOD can serve as a reliable biomarker for assessing the retinal defense mechanisms against oxidative stress and the deleterious effects of excessive light exposure. Elevated MPOD levels offer robust protection against the onset and progression of age-related macular degeneration (AMD), a prevalent cause of vision impairment among the elderly population. MPOD's implications in diverse ocular conditions, including diabetic retinopathy and glaucoma, have been explored, underscoring the real need for clinical measurement of MPOD. The integration of MPOD measurement into routine eye examinations presents an unparalleled opportunity for early disease detection, precise treatment planning, and longitudinal disease monitoring.

CONCLUSIONS

Longitudinal investigations underscore the significance of MPOD in the context of age-related ocular diseases. These studies show promise and elucidate the dynamic nuances of MPOD's status and importance as a measurable, modifiable clinical biomarker.

Low Macular Pigment Optical Density Is Associated with Manifest Primary Open-Angle Glaucoma in Older Women

Background

Lower density of carotenoids lutein and zeaxanthin (L/Z) in the macula (i.e., macular pigment) has been linked to greater risk for age-related eye disease.

Objectives

We evaluated whether macular pigment optical density (MPOD) was associated with manifest primary open-angle glaucoma (POAG) among older women in the Carotenoids in Age-Related Eye Disease Study 2 (CAREDS2).

Methods

MPOD was measured with customized heterochromatic flicker photometry in women who attended CAREDS2 (2016-2019) and CAREDS1 (2001-2004) study visits. Manifest POAG at CAREDS2 was assessed using visual fields, disc photos, optical coherence tomography, and medical records. Age-adjusted linear and logistic regression models were used to investigate the cross-sectional association between POAG and MPOD at CAREDS2, and MPOD measured 15 years earlier at CAREDS1.

Results

Among 426 CAREDS2 participants (mean age: 80 y; range: 69-98 y), 26 eyes with manifest POAG from 26 participants were identified. Glaucomatous eyes had 25% lower MPOD compared to nonglaucomatous eyes [mean (SE): 0.40 (0.05) compared with 0.53 (0.01)] optical density units (ODU), respectively (P = 0.01). Compared with MPOD quartile 1, odds for POAG were lower for women in quartiles 2-4 (P-trend = 0.01). After excluding eyes with age-related macular degeneration, associations were similar but not statistically significant (P-trend = 0.16). Results were similar for MPOD measured at CAREDS1.

Conclusions

Our results add to growing evidence that low MPOD may be a novel glaucoma risk factor and support further studies to assess the utility of dietary interventions for glaucoma prevention.

Assessment of macular pigment optical density of primary open-angle glaucoma patients under topical medication

BACKGROUND

Glaucoma is a progressive, sight-threatening disease. In this study, we aimed to compare macular pigment optical density measurements of the primary open-angle glaucoma (POAG) patients under topical therapy with the control group.

METHODS

This cross-sectional study included 55 eyes of 30 POAG patients and 42 eyes of 22 age- and sex-matched healthy controls. The data of all participants were analyzed retrospectively. Subsequently, patients with POAG were divided into two groups: Group 1 received therapy including prostaglandin analogue (PGA), and group 2 was using anti-glaucomatous drugs other than PGA. All participants underwent detailed ophthalmologic examination, including fundus photography and spectral-domain optical coherence tomography. In addition, macular pigment optical density (MPOD) was measured using the Zeiss Visucam 500 fundus camera. Mann-Whitney U test, Independent samples t-test, and one-way multivariate analysis of variance (MANOVA) tests were used to compare the values between and among groups.

RESULTS

There was no significant difference in age and sex between POAG and healthy controls (p=0.229, p=0.376, respectively). All MPOD values were higher in the glaucoma group than in the control group. MPOD max, MPOD volume, and MPOD area were significantly higher in the POAG group than in the control group (p<0.05 for all). However, there was no significant difference in the mean MPOD (p=0.083). In addition, in pairwise comparisons, the PGA therapy group had significantly higher MPOD values than the control group (p<0.05 for all).

CONCLUSION

MPOD levels increased in patients receiving PGA treatment. In addition, retinal nerve fiber layer thickness was positively correlated with MPOD levels in POAG patients. Therefore, PGAs may have a neuroprotective effect.

Comparative Study of Macular Vascular Density and Retinal Thickness in Myopia Children with Different Microscope Diopters Based on OCTA

In order to study the vascular density and retinal thickness of myopic children, a depth study was carried out on the basis of OCTA microscope. Through the methods of prospective cross-sectional research, statistical analysis, and basic data comparison, the research examination of myopia children under OCTA was successfully analyzed. There were significant differences in the density of superficial capillaries in the whole macular region, inner ring, temporal side of inner ring, and nasal side (P = 0.033, 0.024, 0.018, 0.032), and there was no significant difference in other ranges (P > 0.05). Macular fovea, as the most sensitive part of the retina, has pathological changes, which will also lead to serious negative effects on vision. The limitations of cross-sectional studies include the results of a relatively small sample size. After the study of OCTA in the macular region of children with myopia, it is related to the progressive atrophy of the retina and choroid in the macular region. When there are obvious pathological changes in the macular region, the thickness of the macular region becomes significantly thinner. We found that there was a positive correlation between retinal vascular density and retinal thickness in the fovea and above of myopia. The retinal thickness of the whole macular region, the inner ring and its four quadrants, and the outer ring and its four quadrants were positively correlated with SE (standard error) (all P < 0.05); Foveal ring retinal thickness was not associated with SE.

Macular Pigment and Open-Angle Glaucoma in the Elderly: The Montrachet Population-Based Study

(1) Background: To compare macular pigment optical density (MPOD) and its spatial distribution between eyes with primary open-angle glaucoma (POAG) and control eyes in an elderly population. (2) Methods: The Montrachet study (Maculopathy Optic Nerve and nutrition neurovAsCular and HEarT) is a population-based study including participants aged 75 years and over. All participants had a slit lamp examination, fundus photographs, and a questionnaire about their medical past history and smoking status. Optic disc spectral domain optical coherence tomography was also performed. All glaucoma-suspected patients were convocated to have a new full examination. We only retained one eye with POAG for analysis in the glaucoma group and one eye without optic neuropathy in the control participants group. MPOD measurements were performed with the two-wavelength autofluorescence method (488 and 514 nm). (3) Results: Overall, 601 eyes had MPOD measurements among 1153 participants. Among the 601 eyes, 48 had POAG. The mean age for the glaucoma and control participants was 84.01 ± 4.22 years and 81.94 ± 3.61 years, respectively (p < 0.001). In the multivariable analysis, we could not find any association between POAG and MPOD at 0.5° (p = 0.336). We found no significant difference regarding MP spatial distribution between the two groups (p = 0.408). (4) Conclusion: In this elderly population-based study, eyes with POAG and control eyes without optic neuropathy did not differ in terms of MPOD and MP spatial distribution.

Carotenoids in the Management of Glaucoma: A Systematic Review of the Evidence

Primary open-angle glaucoma (POAG) remains a leading cause of irreversible blindness globally. Recent evidence further substantiates sustained oxidative stress, and compromised antioxidant defenses are key drivers in the onset of glaucomatous neurodegeneration. Overwhelming oxidative injury is likely attributed to compounding mitochondrial dysfunction that worsens with age-related processes, causing aberrant formation of free radical species. Thus, a compromised systemic antioxidant capacity exacerbates further oxidative insult in glaucoma, leading to apoptosis, neuroinflammation, and subsequent tissue injury. The purpose of this systematic review is to investigate the neuroprotective benefits of the macular carotenoids lutein, zeaxanthin, and meso-zeaxanthin on glaucomatous neurodegeneration for the purpose of adjunctive nutraceutical treatment in glaucoma. A comprehensive literature search was conducted in three databases (PubMed, Cochrane Library, and Web of Science) and 20 records were identified for screening. Lutein demonstrated enhanced neuroprotection on retinal ganglion cell survival and preserved synaptic activity. In clinical studies, a protective trend was seen with greater dietary consumption of carotenoids and risk of glaucoma, while greater carotenoid levels in macular pigment were largely associated with improved visual performance in glaucomatous eyes. The data suggest that carotenoid vitamin therapy exerts synergic neuroprotective benefits and has the capacity to serve adjunctive therapy in the management of glaucoma.