28 - Age-Related Macular Degeneration Flashcards
Classified as ___ or ___
dry or wet
Describe Dry AMD
-drusen (white-yellow spots in central retina)
Describe Wet AMD
- responsible for the vast majority of severe vision loss, always occurs in the setting of pre-existing dry AMD
- wet form is caused by presence of a choroidal neovascular memrane (CMV)
What are some risk factors for losing vision?
- smoking
- HTN
- family Hx
- light pigmentation of the skin and irides
What is the gold standard for investigating AMD
fluorescin angiography
Non-pharms?
quit smoking
maintain a balanced diet
Pharmacologic Tx:
Describe the VEGFs and how they work (vascular endothelial growth factor inhibitors)
-decrease vision loss in wet AMD, they inhibit growth and cause regression of new blood vessels in CNV membranes
Pharmacologic Tx:
How are VEGFs administered?
-injected directly into the vitreous cavity of the eye following application of topical anesthesia and antiseptic eye drops, usually povidone-iodine
Pharmacologic Tx:
What are the 4 VEGF examples in Canada?
- ranibizumab (HC approved)
- bevacizumab (off label for wet AMD and also used for colon cancer)
- afilbercept
- pegaptanib (not shown actual improvement in vision so rarely used)
Pharmacologic Tx:
How often and for how long do you give VEGFs
- administer every 4 weeks
- most patients require 1 year or more of therapy
Pharmacologic Tx:
Example of PDT (photodynamic therapy)
verteporfin
Pharmacologic Tx:
How is verteporfin administered?
IV followed by a low level nonthermal laser light
Pharmacologic Tx:
s/e of verteporfin (PDT)
- visual disturbances
- will be sensitive to light for 48 hours after
Formulas of AREDS containing beta-carotene may increase risk of ____ cancer
lung
Lutein 5 mg = _______ 250 mcg
zeaxanthin
Take AREDS w food to decrease nausea that may be associated w ____ dose
zinc
AREDS causes a ____ reduction of AMD-associated vision loss over 7 years
25%
Describe the treatment/recommendation for Dry AMD
- supplement w AREDS
- quit smoking
- self-monitor w Amsler Grid (keep 33cm from face, adequate lighting)
Describe the treatment/recommendation for Wet AMD
- supplement w AREDS
- quite smoking
- self-monitor w Amsler Grid (keep 33cm from face, adequate lighting)
- Retinal specialist to consider VEGF inhibitor
- For rare forms of wet AMD - may use verteporfin (PDT)
Many patients w AMD also develop _______
depression
What would be the reaction with PDT (verteporfin) and tetracyclines?
both cause photosensitivity
