Natural Therapies for Ocular Disorders Part Two: Cataracts and Glaucoma

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Natural Therapies for Ocular Disorders Part Two: Cataracts and GlaucomaAlternative Medicine Review, April, 2001 by Kathleen Head 1 http://findarticles.com/p/articles/mi_m0FDN/is_2_6/ai_74510830/2345678910…26Next AbstractPathophysiological mechanisms of cataract formation include deficient glutathione levels contributing to a faulty antioxidant defense system within the lens of the eye. Nutrients to increase glutathione levels and activity include lipoic acid, vitamins E and C, and selenium. Cataract patients also tend to be deficient in vitamin A and the carotenes, lutein and zeaxanthin. The B vitamin riboflavin appears to play an essential role as a precursor to flavin adenine dinucleotide (FAD), a co-factor for glutathione reductase activity. Other nutrients and botanicals, which may benefit cataract patients or help prevent cataracts, include pantethine, folic acid, melatonin, and bilberry. Diabetic cataracts are caused by an elevation of polyols within the lens of the eye catalyzed by the enzyme aldose reductase. Flavonoids, particularly quercetin and its derivatives, are potent inhibitors of aldose reductase.Most RecentHealth Care ArticlesHealthcare Roundup: Insurance Exchanges Questioned, Health Plans Criticized... Amid the Reform Crossfire, Experts Offer Reality Check Health Reform Looks Uncertain as Prominent Dems Shift Positions Many Ob/gyns Drop Services Because of Liability Risk Medicare Actuary's Reform Report, Part II More »Glaucoma is characterized by increased intraocular pressure (IOP) in some but not all cases. Some patients with glaucoma have normal IOP but poor circulation, resulting in damage to the optic nerve. Faulty glycosaminoglycan (GAG) synthesis or breakdown in the trabecular meshwork associated with aqueous outflow has also been implicated. Similar to patients with cataracts, those with glaucoma typically have compromised antioxidant defense systems as well. Nutrients that can impact GAGs such as vitamin C and glucosamine sulfate may hold promise for glaucoma treatment. Vitamin C in high doses has been found to lower IOP via its osmotic effect. Other nutrients holding some potential benefit for glaucoma include lipoic acid, vitamin B12, magnesium, and melatonin. Botanicals may offer some therapeutic potential. Ginkgo biloba increases circulation to the optic nerve; forskolin (an extract from Coleus forskohlii) has been used successfully as a topical agent to lower IOP; and intramuscular injections of Salvia miltiorrhiza have shown benefit in improving visual acuity and peripheral vision in people with glaucoma.(Altern Med Rev 2001;6(2):141-166)IntroductionPart one of this article was published in the October 1999 issue of Alternative Medicine Review and discussed nutritional and botanical approaches to conditions of the retina. This second part covers alternative treatments for nonretinal disorders: senile cataracts, diabetic cataracts, and chronic open-angle glaucoma.A large percentage of blindness in the world is nutritionally preventable.[1] The author of this comment was referring primarily to the use of vitamin A to prevent corneal degeneration associated with a vitamin A deficiency; however, there is considerable evidence that many other eye conditions, which are leading causes of vision impairment and blindness, also may be preventable with nutritional supplementation, botanical medicines, diet, and other lifestyle changes. In addition, a number of nutrients hold promise for the treatment of already existing cataracts and glaucoma.Senile CataractsSenile cataracts are the leading cause of impaired vision in the United States, with a large percentage of the geriatric population exhibiting some signs of the lesion. Over one million cataract surgeries are performed yearly in this country alone.[2] Cataracts are developmental or degenerative opacities of the lens of the eye, generally characterized by a gradual painless loss of vision. The extent of the vision loss depends on the size and location of the cataract. Cataracts may be located in the center of the lens (nuclear), in the superficial cortex (cortical), or in the posterior subcapsular area. Cataracts are also classified according to their color, which is consistent with location and density of the cataract. Pale yellow cataracts are typically slight opacities of the cortex, subcapsular region, or both; yellow or light brown cataracts are consistent with moderate to intense opacities of the cortex, nucleus, or both; and brown cataracts are associated with dense nuclear cataracts.[3]DiagnosisSymptoms include near vision image blur, abnormal color perception, monocular diplopia, glare, and impaired visual acuity, and may vary depending on location of the cataract. For example, if the opacity is located in the center of the lens (nuclear cataract), myopia is often a symptom, whereas posterior subcapsular cataracts tend to be most noticeable in bright light.[4] Ophthalmoscopic examination is best conducted on a dilated pupil, holding the scope approximately one foot away. Small cataracts appear as dark defects against the red reflex, whereas a large cataract may completely obliterate the red reflex. Once a cataract has been established, a referral for slit-lamp examination, which provides more detail on location and extent of opacity, is recommended.Etiological/Risk FactorsFactors contributing to cataract formation include aging, smoking,[5] exposure to UVB and ionizing radiation,[6] oxidative stress (secondary to other risk factors such as aging or smoking),[7] dietary factors,[8] increased body weight (above 22-percent body fat), central obesity,[9] and family history. Medications and environmental exposures which may contribute to cataract formation include steroids, gout medications, and heavy metal exposure. Cadmium, copper, lead,[10] iron, and nickel[11] have all been found in cataractous lenses. A high level of cadmium in the lens is associated with smoking and can contribute to accumulation of other heavy metals.[10] Conditions which predispose to cataracts include diabetes, galactosemia, neurofibromatosis, hypothyroidism, hyperparathyroidism, hypervitaminosis D, infectious diseases such as toxoplasmosis, and several syndromes caused by chromosomal disorders.[2]12345678910…26Next