Eye Didn't Know!

Alternative Therapies for Glaucoma?

Did you know? It is said that 50% of patients with glaucoma use "alternative" therapies, that is, therapies other than those prescribed by their physician. The rate may be higher in Asian populations. The question is, do they work??? A prominent glaucoma specialist from San Francisco, John Hetherington, M.D., recently reviewed the literature on the subject. He reached the following conclusions:

Vitamins A, B1, B12, C, and E, as well as antioxidant supplements, had no meaningful effect on intraocular pressure or glaucoma progression.

Marijuana decreases eye pressure, but its effects are very short–lived with significant side–effects. Topical application of its components (there are over 400!) has not yet shown to be effective, but is being studied.

Ginkgo biloba increases ocular blood flow and thus may protect the optic nerve. Dr. Robert Ritch is a specialist who has advocated gingko use for glaucoma for many years. Gingko may cause side effects such as bleeding, especially when used with aspirin, so should be used with caution or after consultation with a primary care physician.

There is no evidence that bilberry is beneficial for glaucoma or optic nerve health.

Drinking excess water can raise eye pressure temporarily.

Alcohol can decrease eye pressure temporarily, but obvious toxicity can result with excess!

Meditation produces insignificant reduction in eye pressure.

Acupuncture has not be shown to affect eye pressure.

Exercise has a significant eye pressure lowering effect over time.

In summary, exercise and possibly gingko are the only alternative therapies which currently may be effective in glaucoma. So save your money and keep walking!

Did you also know? Yoga exercises which feature inversion for long periods of time should definitely be avoided in glaucoma, as they can increase eye pressure greatly!

(photo by Joseph Renger, wikimedia commons)

Antioxidants and early Macular Degeneration

Did you know? The makers of antioxidants, including the ones used in the AREDS study, often make vague claims that these vitamins "promote eye health" and thus imply that they are needed by the general population. Yet there is NO evidence that this is so. A new report in the British Medical Journal analyzed the results of nine prospective studies involving nearly 150,000 subjects. They found no evidence that antioxidant supplement therapy decreased the incidence of early macular degeneration. Different studies looked at different substances, but included the following: vitamin A, vitamin C, vitamin E, zinc, lutein, zeaxanthin, alpha-carotene, beta-carotene, beta-cryptoxanthin and lycopene.

Did you also know? The original AREDS study (Age Related Eye Disease Study) showed that a combination of antioxidants and zinc reduced the progression of moderate macular degeneration to advanced vision loss. This is a specific indication for which ophthalmologists prescribe these supplements. This does not equal "promoting eye health" by encouraging the general population to use these supplements.

More Macular Degeneration-Nutrition News

Did you know? There's clearly more to the macular degeneration/nutrition link than what is on the radar screen of most ophthalmologists. A new study showed that vitamins B6, B12, and folate may be protective. A group of over 5000 women at risk for heart disease was randomized to placebo or Vitamin B6, B12 and folate. After seven years, the group taking the vitamins had 41% less visually significant macular degeneration.

Did you also know? The study was designed to assess whether these vitamins would lower heart disease (by lowering homocysteine levels). There was NO difference in heart disease in the two groups!

Fishy news

Did you know that eating fish may help prevent macular degeneration? Two studies in this month’s Archives of Ophthalmology showed that advanced macular degeneration occured less often in those who ate fish regularly compared to those that ate fish rarely. One study examined the eyes and took a dietary survey of over seven thousand subjects. Those who ate fish at least weekly had less than half the prevalence of advanced macular degeneration compared to those who ate fish less than twice a month. Another study showed a 35% decrease in advanced macular degeneration for those who ate more broiled or baked fish (but not fried!). The authors postulate that fish oils may decrease inflammation and decrease the formation of abnormal new blood vessels, both of which occur in advanced macular degeneration. Whether or not fish-oil supplements are helpful in macular degeneration is not known.

(image courtesy wikipedia commons)

Did you also know? The first of these studies also found that drinking milk was related to less early macular degeneration. (Possibly related to its vitamin D content.)

(image courtesy wikipedia commons)

New use for old Chinese remedy?

Did you know? A synthetic version of bear bile, used in Chinese medicine for millenia, is being tested for its ability to prevent cell death which occurs in macular degeneration, glaucoma, and retinitis pigmentosa. TUDCA and UDCA are components of bile, which help us digest fats. Humans have small amounts of these compounds, but bear bile has large amounts. Synthetic versions are available and inexpensive. Researchers at Emory University tested these compounds. When injected into mice, they preserved the function and structure of retinal cells in two different mouse models of human retinal degeneration. Read about it here.

Did you also know? The researchers stress that the compounds they are testing are synthetic, and do not involve harvesting bear bile! In fact, UDCA, or ursodiol, is available orally as a treatment for liver disease.

Beta Carotene and Macular Degeneration

Did you know? A new study has been released in Archives of Ophthalmology, which followed over 22,000 male physicians for twelve years. Half were randomized to take beta-carotene supplementation, half took a placebo. There was NO statistical difference in the incidence of macular degeneration between the two groups. Supplementation had neither a beneficial or harmful effect. This study is notable in its rigorous design, number of subjects, and length of follow-up. The authors are among the most respected in the field of ocular epidemiology.

Did you also know? The well-known AREDS study looked at supplementation with high doses of zinc, beta-carotene, and vitamins C and E. This study showed a modest benefit for those with a high-risk of macular degeneration, (those with significant drusen in their maculas), but no measurable effect for those with no risk factors, since the risk for these patients was low to begin with.

Cataract Cure???

Did you know? A company in Philadelphia, Othera Pharmaceuticals, is testing an eyedrop which they hope will retard the progression of cataracts. A cataract occurs when the natural lens within the eye becomes cloudy. It is thought that one stimulus for cataract progression is oxidation. Othera is testing a compound, OT-551, which is a potent anti-oxidant, and is able to penetrate into the eye. They are testing the compound first in patients who have undergone a vitrectomy (a surgery for retinal problems) because these patients frequently develop cataracts over a short period.

Did you also know? The concentration of Vitamin C in the front of the eye is many times greater than its concentration in the rest of the body. This may help prevent cataracts.

Aloe Vera

Did you know? Aloe vera contains an ingredient which may someday prove useful to inhibit scarring in the cornea. Mannose-6-phosphate is a sugar derived from aloe vera. It has been recently shown to inhibit cultured corneal cells from transforming into scar-like tissue. This may reduce haze formation sometimes seen after injury or after refractive surgery. Read more here.

Did you also know? The haze which sometimes occurs after PRK (photorefractive keratectomy) surgery is very rare today with better lasers providing a smoother surface after surgery.

Aspartame

Did you know? A recent study showed that consumers of diet soda had the onset of cataracts an average of seven years later than non-drinkers. The authors postulated that aspartame may inhibit changes in lens protein which lead to cataracts. This study was small, (216 patients), retrospective, and may have had confounding influences, but it's an interesting observation. Diet soda on the rocks?

Did you also know? Cataract surgery is more successful than ever, with expert surgeons able to remove the cataract in 10-15 minutes, often with only eyedrops as an anesthetic!

Lutein and Zeaxanthin?

Did you know? The nutrients lutein and zeaxanthin are found within the macula of the human eye, the area responsible for fine vision and the area damaged in macular degeneration. They are pigments, and may serve to protect against damage from light and oxidation. These pigments are found in high quantities in green leafy vegetables, such as spinach. Population studies have shown that those with higher dietary intake of these pigments have less macular degeneration. There is no evidence yet that taking supplements has a protective effect.

Did you also know? A large clinical trial, called AREDS II, (Age Related Eye Disease Study II), is investigating the use of lutein and zeaxanthin supplements, as well as the role of omega III fatty acids, in macular degeneration. The five year study began in 2005, so we will all eagerly await its results. Read more here: lutein and zeaxanthin here: AREDS I or here: AREDSII

Smokeless tobacco

Did you know? A new study, conducted in rural India and published in the British Journal of Ophthalmology has linked the use of chewing tobacco to the formation of cataracts. Nearly 4,000 subjects were examined. After adjusting for age and gender, users of smokeless tobacco had a 67% higher risk of cataracts than those that did not. Interestingly, there was no association with the use of cigarettes. Read more about it here: bjo

Did you also know? India has been a leader in the development of hospitals devoted to high volume, low cost or charity cataract surgery, subsidized by charging those who are able to pay.