Macular Pigment in Glaucoma
The macular pigment tissue is critical to visual function and protecting the retina from oxidative damage caused by free radicals.
Any time an eye disease infringes on central vision, the macular pigment is affected. The loss of macular pigment can also affect glare sensitivity, or the loss of vision in very bright lighting. A reduced or unhealthy macular pigment also makes it difficult to see properly under low-contrast or low-light situations, such as driving at night, stepping up on a sidewalk in the shadows or walking through a dim garage. Glaucoma patients also often experience glare sensitivity, and until recently experts have not exactly been sure why.
The relationship between macular pigment and glaucoma is an emerging area of interest for scientists. Studies have measured the macular pigment in glaucoma patients and discovered a correlation between the health and thickness of the macular pigment and the retinal ganglion cells, which are neurons that link the eye to the brain and which are known to perish as glaucoma progresses. The health and proper function of these cells is essential to sight. Once the retinal ganglion cells die, they are not replaced. Since a substantial amount of retinal ganglion cells are concentrated in the macula, tissue loss in this region can potentially indicate glaucoma-induced damage.
Macular Pigment Optical Density
Let’s look at why the macular pigment is important to vision.
This layer of tissue helps protect the macula, which is the area of the retina responsible for color vision, fine detail and visual acuity. Macular health is important to reducing sensitivity to light and improving contrast sensitivity (the ability to distinguish an object from its background) and glare recovery time. A robust macular pigment enables better glare recovery, or the recovery from temporary blindness caused by very bright light.
The macular pigment helps to protect the retinal cells from free radicals triggered by elements like stress and the sun’s UV rays. By neutralizing these free radicals, the macular pigment can prevent related inflammation as well as damage to the muscles and blood vessels.
The macular pigment is measured by its density. Research demonstrates that low macular pigment optical density (MPOD) increases the risk of vision loss from glaucoma as well as age-related macular degeneration and diabetic retinopathy. Fortunately, this is a modifiable risk factor, as there are ways to restore and replenish the macular pigment to prevent or delay the development of eye disease.
Importance of Replenishing the Macular Pigment in Glaucoma
The macular pigment is composed of three antioxidants called carotenoids, and it is positively and significantly related to the dietary intake of two of these carotenoids (lutein and zeaxanthin). It is believed the carotenoids’ anatomic, biochemical and optical properties make them ideal candidates to enhance visual function, so macular pigment measurements in glaucoma patients may be useful to evaluate visual function.
Since patients with self-reported glare have been found to have low MPOD, getting enough macular carotenoids through diet or nutritional supplementation may help to replenish the macular pigment and prevent vision loss from glaucoma.
Most people’s daily diets do not include enough of the eye-friendly antioxidants they need to make a noticeable difference in the macular pigment. Also, one of the carotenoids that makes up the macular pigment, meso-zeaxanthin, is not found in nature — it has to be produced in the eye from lutein and zeaxanthin. As we age, our body’s natural ability to produce meso-zeaxanthin slows down, making it critical to get meso-zeaxanthin and the other carotenoids through nutritional supplementation.
Recent studies conducted by glaucoma researchers have noted significant improvements in visual field sensitivity among glaucoma patients who have taken Lumega-Z, which is a medical food that contains all three macular carotenoids and a potent blend of antioxidant and anti-inflammatory ingredients.
For more information about replenishing your eye’s macular pigment and fighting the effects of glaucoma and other sight-stealing diseases, please contact Guardion Health Sciences today.