A lumbar sympathetic nerve block is a special test to help your doctor find the cause of your symptoms. During the test, an anesthetic (numbing) medication is injected near your spine. This âblocksâ the sympathetic nerves in that region.
Lutein is an antioxidant carotenoid a pigmented nutrient that is responsible for the yellow colors of fruits and vegetables and is present in the highest quantities in dark, leafy green vegetables. You're born with a certain amount of lutein in your eye, but your body doesn't reproduce it.
Lutein and zeaxanthin are carotenoids, a class of plant-derived vitamins that includes beta-carotene; both are present in leafy green vegetables and, when consumed, they accumulate in the retina. Prior studies had suggested that diets high in lutein, zeaxanthin, and omega-3 fatty acids protect vision. Before the AREDS2 study finished, manufacturers began marketing supplements based on the study design. In AREDS2, participants took one of four AREDS formulations daily for five years.