Guest blog post taken from content presented by Dr. Steven F. Sopher, OD, Lens ‘n Eye, from the Eyemaginations Premium Webinar Series
Age-Related Macular Degeneration(AMD) affects approximately 15 million people in the U.S. and is the leading cause of blindness over age 55. AMD impairs central vision, is irreversible, and currently has no cure.
As gatekeepers of eye care, optometrists play a critical role in preventing vision impairment from macular degeneration. The role of nutrition, including carotenoid intake, is receiving increasing attention for its potential in preventing age-related macular degeneration.
Doctors have been searching for what can protect the macula from age-related macular degeneration. Oxidative stress is considered to be an important, but modifiable, factor in the etiology of AMD. So, while we know that AMD is an oxidative process, what causes this oxidation?
Oxidative damage is caused primarily thru two mechanisms:
- production of reactive oxygen species (free radicals or unstable molecules)
- Photo-oxidative damage to the photoreceptors and the posterior retinal pigment epithelium (RPE)
Both mechanisms lead to oxidized lipids, particularly, polyunsaturated fatty acids, which are incompletely eliminated through the choroidal circulation and accumulated under the photoreceptors in the form of drusen that characterize early-stage maculopathy.
So what really protects us?
Research shows that what protects us is macular pigment. Macular pigment plays an important role in protecting against ocular damage, optimizing visual function and minimizing AMD pathogenesis.
The carotenoids, lutein, zeaxanthin and meso-zeaxanthin make up the macular pigment layer. The carotenoids scavenge free radicals, minimizing the ability of these reactive oxygen species to damage cell membranes. Additionally, the carotenoids filter UV-Blue light reducing photo-oxidative damage to the photoreceptors and the retinal pigment epithelium cells.
The practice of primary care optometry has changed dramatically in the last decade in terms of managing patients at risk for AMD or with active disease. And as primary care optometrists, we now play a much more active role in diagnosing, monitoring and treating AMD.
The initial clinical evaluation should include the features typical of a comprehensive adult medical eye examination with particular attention to screening protocols for evaluation of AMD risk.
Since there is growing and compelling evidence concluding that insufficient levels of macular pigment density substantially increase the risk for developing macular degeneration by as much as 40 percent, we must incorporate technology that can measure macular pigment density and include this as part of every comprehensive eye examination that we perform.