RPE I Flashcards
(46 cards)
What is RPE
The outermost layer of the Retina that separates it from the choroid
T/F anywhere that retina is present RPE is also present
True
Is there retina at the optic nerve?
No, so no RPE either
What must light pass through to reach the RPE
All the layers of the retina
What are the layers of the retina from inner to outer
Inner: inner plexiform layer Inner nuclear layer Outer plexiform layer Outer nuclear layer Inner segments Outer segments Outer: RPE
Non pigmented ciliary epithelium is continuous with this
Retina
The pigmented epithelium is continuous with this
RPE
Approximately how many RPE cells do we have?
4-6 million
Do RPE have the ability to regenerate
No
Where is the RPE cell density the greatest
At the fovea
How photoreceptors face a single RPE cell
30-40
Apex of the RPE faces this
Apex of the photoreceptors outer segment
What are the major functions of the RPE cells
Secretion (VEGF and PEDF) Phagocytosis (of metabolic wastes) Visual cycle Glia Epithelial transport (H2O, Cl, vitamin A, glucose) Light absorption
What photoreceptor discs are shed in the morning
Rod discs
What photoreceptor discs are shed in the evening
Cone discs
When are our rods used
At night in dark environments
When do we use our cones
In the daytime bright conditions
What are present in th outer zone of the RPE
Mitochondria
What are present in the middle zone of RPE
Nucleus of RPE, Golgi and ER
What are present in the inner zone of the RPE
Melanocytes
Know what a drusen is
See slides 21-23
What happens in macular degeneration
You have a buildup of hydrophobic materials in Bruchs that causes the RPE to malfunction and become sick and nutrients cant come in and wastes cant get out. This can cause cracks to corm in Bruch’s membrane, where blood vessels will creep in
What happens in geographical atrophy
RPE drop out and you can see choroid
What is the difference between wet and dry MD
Wet: there are blood vessels that creep into the macula
Dry: just drusen
