Retina B7 Flashcards
____ is the outermost layer of the retina
RPE
____ is the barrier between the choroid and retina
RPE
Eye has to be ______ to assess RPE
dilated
Anywhere you see ______ behind it is RPE.
retina
No retina at ________, thus no RPE.
optic nerve
LIght must pass through what to reach the RPE.
All of the layers of the retina
Towards the vitreous
Vitreed
Towards the sclera
Sclerad
Away from the center of the eye
outer
Towards the center of the eye
Inner
Layers of retina
Inner plexiform layer Inner nuclear layer Outer plexiform layer Outer Nuclear layer Inner segments Outer segments RPE
4-6 million cells that have no regenerative capacity
RPE cells
RPE cell density is greatest in the region of the ______.
fovea
Each RPE cell face about _____ photoreceptor outer segments.
30-40
Apex of RPE faces Apex of ___________ outer segment.
photoreceptor
Layers of Bruch’s membrane starting with RPE.
Basement membrane of RPE Inner collagenous layer Elastic layer Outer collagenous layer Basement membrane of choriocapillaris
What are the major functions of the RPE?
Secretion - VEGF Phagocytosis Visual cycle Glia Epithelial transport Light absorption
Apical microvili of the RPE engulf Rods and cones at different times. When do these happen?
Rod discs are used at night and are shed in the early morning.
Cone discs are active all day and at the end of the day (evening) are shed
Where is the mitochondria located?
outer zone of RPE
Where is golgi apparatus?
Middle zone
What are the steps of degradation of rod outer segments in the RPE?
Phagosome engulfs shed cell
Meets with Lysosome
Forms phagolysotome
Gets digested and diposted into the INNER COLLAGENOUS ZONE OF BRUCH’s
When you have excessive drusen what is the problem?
RPE is at risk, not functioning as it should
Smokers have more drusen (epithelial waste)
Age related Macular degeneration.
Build up of hydrophobic material laid down in bruch’s… Creates choroidal neovascularization
Age related Mac degen.
Bruch’s membrane capillaries are fenestrated
Retinal capillaries are not fenestrated
YOU don’t want blood vessels creeping into fovea
What percent of age mac degen is wet?
10%, blood moving into macular area is going to distort vision
What are some injectable anti vascular endothelial growth factor?
anti-VEGF
Avastin ($50)
Lucentis and Eyelea ($1800-2000)
(they do the same thing)
Blood retina barrier has what between the RPE cells
Tight junctions for communication between the non-fenestrated endothelial cells of the retinal capillaries
