Retinal Topography And Vasculature

Question 1

What is the function of the retina

Answer 1

Light energy is transformed into neural signal

Question 2

What are the first 3 cells of the visual pathway

Answer 2

1. Photoreceptors
2. Bipolar cells
3. Ganglion cells

Question 3

What must pass through all three layers of the retina in order for a neural signal to be phototransduced

Answer 3

Light

Question 4

How many layers are there of the retina

Answer 4

10

Question 5

The 9 inner layers of the retina are called this

Answer 5

Sensory or neural retina

Question 6

The outermost layer of the retina is called

Answer 6

RPE

Question 7

T/F all regions of the retina are the same

Answer 7

False

Question 8

What are the 10 layers of the retina from outer to inner

Answer 8

RPE- retains pigment epithelium 
PRL-Photoreceptor Layer
ELM-External limiting membrane 
ONL-outer nuclear layer
OPL-outer plexiform layer
INL- inner nuclear layer
IPL- inner plexiform layer
RGCL- retinal ganglia cell layer
RNFL- retinal neural fiber layer
ILM- inner limiting membrane

Question 9

What layers do the photoreceptors span

Answer 9

Outer retina

1. Photoreceptor layer
2. External limiting membrane
3. Outer nuclear layer
4. Outer plexiform layer

Question 10

What is the role of the photoreceptors

Answer 10

Absorb light photons and convert them into an electrochemical event

Question 11

What are the 2 kinds of photoreceptors in the retina

Answer 11

Cones and rods

Question 12

How many cones are there in the retina

Answer 12

5-6 million

Question 13

When are cones used

Answer 13

Bright illumination

And color vision

Question 14

How many photopigments are there for cones

Answer 14

3

Question 15

What are the S-cones used for

Answer 15

Blue cones (420 nm)

Question 16

What are M cones used for

Answer 16

Green cones 531 nm

Question 17

What are L cones used for

Answer 17

Red cones

588 nm

Question 18

What are only photoreceptors found in the fovea

Answer 18

Cones

Question 19

What photopigment is not found in the fovea

Answer 19

S cones

Question 20

How rods are there

Answer 20

92-120 million

Question 21

When are rods used

Answer 21

Dim vision and movement detection

Question 22

What photopigment is found in rods

Answer 22

Rhodopsin

Question 23

Where the peak amount of rods found

Answer 23

4.5 mm outside of the fovea

Question 24

Where are rods not found

Answer 24

In the fovea

Question 25

What are some of the different cells found in the retina

Answer 25

``` Horizontal cell processes and bodies Rod bipolar cells Cone bipolar cells Amacrine cells Astrocytes ```

Question 26

Where are the major output cells found

Answer 26

In the retinal glial cell layer

Question 27

What are the first cells to die in glaucoma

Answer 27

The retinal ganglia cells

Question 28

What is the thickness range of the range

Answer 28

80-320 um

Question 29

What is the central retina used for

Answer 29

Cones Color vision Fine detail

Question 30

What is the peripheral retina used for

Answer 30

Rods Night vision Motion detection

Question 31

What is the macula

Answer 31

Only area of the retina that contains more than 1 layer of retinal ganglion cells High levels of carotenoids

Question 32

What is the fovea

Answer 32

The central depression of the retina

Question 33

Where is the rod free zone in the fovea

Answer 33

In the center, there are only cones here

Question 34

How are cone axons oriented in the outer plexiform layer

Answer 34

Obliquely

Question 35

How are the retinal cells displaced in inner retinal cells

Answer 35

Laterally

Question 36

What is the foveola

Answer 36

The center of the fovea Dense packing of cones here Can contain up 10 rows of cone nuclei

Question 37

What is Henle's fiber layer

Answer 37

Cone inner fibers that are oriented obliquely with the fovea

Question 38

What is the parafovea

Answer 38

The highest accumulation of bipolar and retinal ganglion cells Where rods have their peak density

Question 39

What is the perifovea

Answer 39

Axons of henles fiber layer resume their vertical orientation Begins where the RGC layer has been reduced to 4 rows that terminates where it contains only 1 row

Question 40

What is the peripheral retina and where does it terminate

Answer 40

Rod dominant region | Terminates at ora serrata

Question 41

What is the ora serrata

Answer 41

Peripheral terminations of the retina | It transitions into ciliary body

Question 42

What does the neural retina become

Answer 42

Non-pigmented ciliary epithelium

Question 43

What does the RPE become

Answer 43

The pigmented ciliary epithelium

Question 44

What supplies blood to the outer retina

Answer 44

Choroid

Question 45

What supplies blood to the inner retina

Answer 45

Retinal vessels

Question 46

What other vessels supply to the retina

Answer 46

Short posterior ciliary artery Cilioretinal artery Central retinal artery Central retinal vein

Question 47

What is the importance of the cilioretinal artery

Answer 47

It is present in 10-20% of the population | It supplies the macula

Question 48

Where does the central retinal artery enter at

Answer 48

Lamina cribrosa | Slightly nasal

Question 49

What tunic layer does the central retinal artery lose? What replaces it

Answer 49

Tunica elasticum Tunica media

Question 50

What is the other most layer of the central retinal artery | What is its function

Answer 50

Tunica adventitia Control of vasomotor tone is auto regulated here

Question 51

What does loss of pericytes and endothelial cells cause

Answer 51

Microaneurysms, hemorrhages, exudates, and fluid in the macula

Question 52

What causes the dot and blot hemorrhages

Answer 52

Deep capillary plexus

Question 53

What causes the flame shaped hemorrhages

Answer 53

Superficial capillary plexus

Question 54

What is the foveal avascular zone

Answer 54

No blood vessels here | It's all about getting the max amount of light to the photoreceptors

Question 55

Why are retinal artery veins occlusion so bad

Answer 55

Because the ganglia cells cant get their blood They are the cells that communicate with the brain

Question 56

What veins drain the retina and orbit

Answer 56

Superior ophthalmic vein Inferior ophthalmic vein Central retinal vein