L1 Macula Flashcards
What is early AMD?
- Dry changes (soft drusen, hyper and hypo pigmentation of RPE)
What is late AMD?
- Either: End stage dry AMD (geographic atrophy) or presence of
neovascular AMD
AREDS classification of AMD
Risk factors of AMD
why do we get drusen?
1.damage to photoreceptor by oxidative stress
RPE cells force out unwanted or damaged proteins or lipids that can accumulate in brutes membrane
What is drusen?
abnormal lipid deposits generated by photoreceptors.
between the basal lamina of the RPE and the inner collagenous layer of Bruch’s membrane
pale yellow
What causes Dry AMD?
What are the symptoms of Dry AMD?
-gradual impairment of vision
-later stages:
+ve scotoma
difficulty recognising faces
-difficulty seeing in dim light
painless
What are the signs of Dry AMD?
hard/soft drusen
focal hypo/hyper pigmentation of RPE
geographic atrophy
drusenoid rpe detachment (later stages ^)
What are the differences between hard and soft drusen?
hard:
- small yellow/white spots
-part of normal age processing of eye
-less than half retinal vein width
soft
thickening of Bruch’s membrane
-Larger in size, may coalesce to form confluent drusen ( >125 micron)
Can form drusenoid pigment epithelium detachment
-should be monitored
soft drusen
hard drusen
what is hyper pigmentation?
image
RPE cell proliferationRPE cell migration
Increase in melanin in RPE cells
What is hypopigmentation?
image
seen as small patches of mottled pigment RPE layer thinning
RPE cell atrophy
Reduction in melanin in RPE cells
What is Geographic atrophy ?
1.atrophic areas enlarge and coalesce
2. underlying choroidal vasculature becomes visible
- Advanced GA: visible scleral tissue, loss of drusen,
severe central vision impairment