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Flashcards in Ocular Nutrition Deck (31)
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What factors contribute to pathophysiology in glaucoma?

Serum autoantibodies to optic nerve head glycosaminoglycans are seen in patients with glaucoma


What are current therapy in glaucoma

Intraocular pressure lowering medication
Adjunct therapies
Neuro protection issues


What influences IOP

Alcohol decreases osmosis. Large consumpion of beer is similar to water provocative tests


What are the benefits of caffeine

Has antioxidants
Increases metabolism
Secondary benefis to blood flow in eye


What is the relationship bet mj and IOP

lowers IOP 3-4 mm. Problem is that its short term and minimal efficacy. Have to repeat the dose every three hours which isn't practical


What is the fat intake in regards with glacoma

very little research but dietary fat may modulate the availability of intraocular prostaglandins. Total fat intake was not associated with glaucoma however when you have a high ratio of omega 3 to 6 polyunsaturated fat, you increase the risk of POAG


What is ginko biloba

reduces platelet aggregation
reduces the development of free radicals
increases vasodilation
reduces blood viscosity
quenching of free radicals
*In humans it increased end diastolic flow velocity in the opthalmic artery


We're not prescribing ginko biloba

Bc we're not seeing that much good out of it. Not a lot of research


How do carotenoids effect cataracts

intake of lutein and zeaxanthin yeilded a 22% reduction in risk for cataract surgery


How does vitamin C help with cataracts

Vitamin C supplements taken over 10 years are 45% less likely to require cataract surgery


What did the Blue Mountain Eye study confirm

Long term use of daily multivitamins protected against the development of nuclear and corticol cataracts.


What did the Beaver Dam eye study conclude

There is NO relationship between cataracts and increased dietary intake of vitamins c, e, and alpha carotene or beta carotene


What did AREDS study find

9- vitamin c, vitamin e and beta carotene has no effect on cataracts
32- centrum multivitamins are associaed with decreased risk of nuclear cataract


What does cataract formation involve

Multifactorial: diet environmental factors (sun and radiation)
Medical conditions (diabetes)
Use of systemic/topical medications


What is age related macular degeneration

major cause of blindness
1.2 mill US people affect
pupils become smaller with age
yellowing of lens


What are the risk factors for amd

smoking, age, family history


AMD occurs in early life. T/F



What is the pathogenesis of dry amd

Exact pathogenesis is unknown but oxidative damage due to higher oxygen levels and reactive oxidation species, and blue light


Does a dietary intake of omega 3 fatty acids reduce the liklihood of AMD

Yes, reduced atrophy in ind with bilateral drusen at baseline


Does Vitamin C help AMD

Unclear but most studies say no


Does Vitamin E help AMD

Unclear, but most say no, some say they found it protective under some circumstance


What about carotenoids and AMD

Some show beneficial effect some other no effect. REsults are not uniform


What are macular carotenoids capable of

Quenching the reactive oxidative species, thus protecting the RPE from oxidative damage. They absorb blue light


How do you measure Macular Pigment Density

A machine named QuantifEye works on the principle that:
1. macular pigment absorbs blue light
2. more macular pigment = longer time you see flicker
3. Results are quantified via software


How does the Heterochromatic flicker photometry work (quantifye)

HFP technique is based on the fact that MP acts as a filter which effects the sensitivity to different wavelengths. The subject presses a button when flicker becomes available. the blue/green ratio is changed after each button press. As the blue/green luminances get closer, flicker sensitivity is reduced. The difference between the minimum for central viewing and for peripheral vieweing provides a measure of macular pigment density in the central fovea.


What is the affect of carotenoids and smokers

High doses of beta carotene alone or in combination with vitamin e are associated with a significant risk of developing lung cancer in smokers


How does zinc affect AMD

IT may help AMD but high doses can lead to hospitalization for genitourinary causes. Also high doses in AH were more likely to develop cataracts than healthy controls


T/F you can see beneficial affects with AMD without beta caratene and just lutein and zeaxanthing



What does the Blue Mountain eye study confirm about above median intake of beta carotene, vitamin c, vitamin e, and zinc

35% reduced risk of AMD


There is evidence that carotenoids with a combination of vitamins reduce risk of AMD