age related macular degen Flashcards
what is age related macular degen?
progressive condition affecting macula
where is the macula?
back of retina
what is the function of the macula?
central vision
helps distinguish colour and fine detail
what is the most common cause of blindness in the UK?
AMD
what are the two types of AMD?
wet - neovascular
dry - non-neovascular
which is the most common type of AMD?
dry - non-neovascular accounting for 90% of cases
what are drusen?
yellowish deposits of proteins and lipids between retinal pigment epithelium
and bruch membrane
when would drusen be seen?
a few small drusen - common in elderly
many and large - pathological of AMD
apart from drusen how may AMD present?
atrophy of retinal pigment epithelium
degen of photoreceptors
in wet AMD what specific signs occur?
wet - new vessels forming in choroid layer and into retina
vessels can leak - oedema and vision loss
how might the neo-vascularisation be targetted in AMD?
new vessels stimulated by vascular endothelial growth factor
target VEGF
what are RF for AMD?
age
smoking
fam Hx
CVS disease
obesity
poor diet - lack of vitamins and more fat
how does vision change present?
unilateral
gradual loss of central vision
reduced visual acuity - worsening ability to read small writing
crooked or wavy appearance to straight lines
what is metamorphosia?
crooked or wavy appearance to straight lines
how fast does neovascularisation present?
more acute than dry
vision loss in days and progress to complete blindness in 2-3yrs
can progress to bilateral