Eye Flashcards
What types of AMD are there?
early: no/ minimal vision loss
late: vision loss:, can be dry (geographic) or wet (neovascular)
dry; more common late form of AMD that develops from years to decades. Gradual breakdown of light sensitive cells in the macular.
wet; quick loss of vision cells, weeks to months, abnormal growth of vessels under the macular
What are the risk factors of AMD?
non-modifiable: age, genetics, family history
modifiable: smoking, diet and lifestyle
What are the four ways to diagnose AMD?
retinol photograph: detailed image of the retina which serves as a basis for comparison of future eye examinations.
fluorescein angiogram: fluorescein dye is injected into the vein of the arm. The dye rapidly reaches the eye, circulating through the retina to highlight any abnormalities.
Optical coherence tomography (OCT): standard test for AMD- non-invasive cross sectional view of the retina
Amsler grid: Can be used at home and obtained from an optometrist to self-monitor. A grid is displayed and if it is morphed, you need to follow up.
What is the pharmaceutical treatment for AMD?
anti-VEGF-
VEGFs work by binding to the receptor in the eye which causes the growth of abnormal blood vessels which can leak–> vision declines.
anti-VEGF binds to VEGFs, preventing it from binding to receptors. Works by injecting it into the eye after cleaning and freezing the eye.
e.g. Lucentis, Eyelea, Beovu, Vabysmo
What is the greatest risk factor for AMD?
Smoking; oxidative damage to the retinal pigment epithelium (RPE) which supports the structure and functioning of the retina.
How do leafy greens help reduce the risk factor for AMD?
5 servings of leafy greens; contains lutein and zeaxanthin. e.g. kale, spinach, broccoli, parsley, asparagus.
- the macular is is dense in the carotenoids and helps to reduce amyloid-beta plaques.
- nitrates help with vasodilation of the micro blood vessels in the eye
- zinc is a cofactor for antioxidant enzymes; superoxide dismutase and catalase.
Why are antioxidants important for AMD?
retina is susceptible for oxidative stress from high exposure to oxygen, high concentration to polyunsaturated fats and exposure to light. Hence antioxidants likely promote health cell function for the eye.
What food groups help reduce AMD?
Low GI foods; ranking of how fast the carbohydrate in a food is digested and absorbed into the bloodstream. (high = fast release, low = slow release).
e.g. buckwheat, barley, quinoa, white, brown, basmati rice
fish (twice a week): omega 3 and docosahexaenoic acid (DHA)
veggies, fruits, handful nuts (2-3 times/week)
What types of supplements are used for AMD
AREDS- contains zinc, copper, vitamin C, E, lutein, zeaxanthin
e.g. Bausch + Lomb Preser Vision Eye Vitamin and Mineral supplement (AREDS 2 formulation).
What are the rules for wearing contact lens?
- do no mix water with CL as it can cause infections. Hence, care when washing face, shower, bath, hot tubs, swimming, etc. When washing hands, dry completely before handling contact lens.
- saline is a disinfectant
- solutions should not be topped up or decanted (dilutes disinfectant ingredient)
- CL cases should be changed every 3 months
- can’t sleep with contact lens on unless prescribed
What is orthoK
used to control myopia (near-sightedness).
- helps to reshape the corneal epithelium
- overnight wear –> rx free during day
- use RGP solutions and hydrogen peroxide, dont use water
What are soft multifocal lenses used for?
contact lenses with multiple prescriptions all in one lens used for slowing down myopia
What is atropine used for?
myopia- paralyses/ relaxes smooth ciliary muscles in the eye causing it to dilate. It comes as 1% but needs to be compounded to 0.01%.
What is the common driver for dry eye?
Meibomian gland deficiency. Lipid layer of the film is not sufficient.
What are the tests for dry eye?
- put a strip in the eye to see how much tears come out
- you can get a photo of the lipid on the eye
- meibography: look under the eyelids if there is dropping out of Meibomian glands. If there are a lot dropping, not much lipid is produced = dry.
