Eye posterior segment Flashcards
describe what happens to vitreous with age
collagen forms bundles. Floaters, flashes, hemorrhage, curtain/veil as vitreous detaches from retina
arterial supply of eye
internal carotid branches to ophthalmic a branches into central retinal (no redundancy) and ciliary arteries (choroidal, lots of redundancy).
how do you test for vascular obstruction
flourescein dye injection (arteries in 10 seconds, veins in another 5 seconds)
where do photoreceptors and RPE cells get blood flow from?
they are avascular. supply comes from choroidal circulation
artery vs vein occlusion
artery=cherry red spot (opacification). vein=hemorrhage
in what diseases do we see neovascularization
prolific diabetic retinopathy=retinal
wet macular degeneration=choroidal
NPDR: when is it seen? characteristic findings?
early DR. No neovascularization. Microaneurysms, cotton wool spots. Increased vasc. permeability leads to edema and lipid deposits (hard exudates)
PDR: when is it seen? what can it lead to? tx?
later stage DR. neovascularization of disc and elsewhere. Can lead to hemorrhage. tx: anti-VEGF and laser burn outer retina
what is the macula used for
reading and seeing faces
progression of ARMD. tx?
dry (non-exudative, non-neovascular) then wet. Anti-VEGF is tx
what are the four descriptors of the optic nerve
cup, color, contour, margins
blood supply to optic nerve
mostly by posterior ciliary arteries
optic neuritis is often linked to
MS
papilledema: pathophys? complaints?
bilateral disc swelling secondary to increased intra-cranial pressure. Transient (seconds) vision loss. NO APD b/c its bilateral
Giant cell arteritis: pathology? complications?
intimal proliferation leading to obstruction of CRA
