5 Topography & Vasculature Flashcards
In the retina, 1st order neurons are ______
2nd order ________
3rd order _______
Photoreceptors
Bipolar cells
Retinal ganglion cells
When light passes through the layers of the retina to be converted into neural signal, what order neurons come into contact with the light first?
3rd order neurons
Retinal Ganglion Cells
After light passes through the retina.. what order does it go in to send signals to the brain?
1st order neurons (photoreceptors)
2nd order
(Bipolar cells)
3rd order
(Retinal ganglion cells)
For cones, what cones are around 420nm, 531nm, and 588nm?
Where are they found?
S-cones (blue cones) SHORT wl
M-cones (green cones) MEDIUM
L-cones (red cones) LONG
ONLY IN FOVEA
Approximately how many S cones are there in the center of the fovea?
NONE. Literally none, don’t even bother to look
Rods all have _______ while cones have _______ photopigments
Rhodopsin
Conopsin
What’s the outermost layer of the retina? 10th layer
Retinal pigment epithelium
RPE
List the outer retinal layers
Photoreceptor layer
External limiting membrane
Outer nuclear layer
Outer plexiform layer
The role of a ____ is to absorb light photons and convert them into an electrochemical event (nerve signal)
Photoreceptor
There are 5-6 _____ cones with (10% total in fovea)
Contain photopigments called ____
Million
Conopsins
Retinal thickness ranges from 80um to ____um
_____ is 150-200um
At the equator of the ______ it’s 120-180um
_____ is 80um
320um
Fovea
Retina
Ora serrata
In the _____ Retina there’s a dense population of ROD photoreceptors. Designed for night vision and motion detection
Peripheral
In the ____ Retina there’s a dense population of CONE photoreceptors. Designed for color vision and fine detail discrimination
Central!
Central=Cones
C=C
What eye structure is 3.5mm from temporal margin of optic disc, 1mm inferior to center of optic disc, and the only layer of the retina to contain more than 1 layer of retinal ganglion cells?
MACULA
The central depression in the macula that’s 1.5mm in diameter is the _____
Only has _____ photoreceptors!!
Fovea
CONE
What’s the central 350um of the fovea that has cones packed so dense that they appear as rods?
Thinnest region of the _____ pole 150-200um
Foveola
Posterior
Cone fibers that are oriented obliquely within the fovea are called _______ fibers.
Henle
Annular rings:
Which has the highest accumulation of bipolar and retinal ganglion cells, extends 05.mm from the foveal rim, and is where rods reach their peak densisty?
Which surrounds the other ring and has Henle’s fiber layer in vertical orientation? Begins where RGC layer is reduced to 4 nuclei rows
Parafovea
Perifovea. (Per=OUTSIDE of the para fovea (which is outside of fovea))
Where does the peripheral retina terminate?
Ora serrata
Where does:
Peripheral termination of retina occur
Neural retina becomes NPCE
RPE turns into pigmented ciliary epithelium
(All from one thing)
Ora serrata
Retinal vasculature:
Outer retina is supplied by _____
Inner retina is supplied by ______
Choroid
Retinal vessels
Only 10-20% of the population has a ______ artery. It supplies the macula
Cilioretinal
Where does the central retinal artery enter the eye?
It’s positioned slightly ____ in the nerve and _____ to central retinal vein
Enters eye through lamina cribrosa of Optic disc!
Nasal; nasal
What does the central retina artery lose upon entering the eye which makes it distinguishable from muscular arteries found elsewhere in the body?
What replaces this?
Tunica elasticum
Tunica media
