Visual Pathway

Question 1

what does the choroid layer do?

Answer 1

provide nourishment

Question 2

macula is rich in what

Answer 2

cone cells

Question 3

why are there so many cell layers in the retina

Answer 3

reduce intensity of the light

Question 4

how many layer groups in the retina

Answer 4

two - neuronal and non-neuronal

Question 5

what do bipolar cells connect

Answer 5

photoreceptors to the ganglion cells

Question 6

what do ganglion cells do

Answer 6

give off an axon that goes on to become the optic nerve

Question 7

positioning of optic disc relative to fovea

Answer 7

slightly medial

Question 8

what type of cells make up first order neuron

Answer 8

bipolar cells

Question 9

what type of cells make up second order neuron

Answer 9

ganglion cells

Question 10

where are first and second neurons located?

Answer 10

in the retina

Question 11

are eyes in PNS or CNS?

Answer 11

ALL CNS

Outgrowth of diencephalon

Question 12

path of ganglion cells

Answer 12

run over retina to optic disk/blind spot

forms optic nerve

optic nerve runs to LGN (thalamus)

Question 13

third order neuron nerve path

Answer 13

LGN in thalamus via optic radiation to primary visual cortex

Question 14

as an outgrowth of the diencephalon it has…

Answer 14

meninges

Question 15

optic nerves pass out through which foramen

Answer 15

optic canal

Question 16

the dura forms what around the eye

Answer 16

the sclera

Question 17

the sub-arachnoid space forms what

Answer 17

the choroid space

Question 18

problems associated with sub-arachnoid space

Answer 18

build up of CSF
papilloedema
compress nerves and blood vessels

Question 19

why does papilloedema occur?

Answer 19

compresses central retinal vein preventing venous drainage from the eye - swells the optic disk

Question 20

optic radiation allows what to go where

Answer 20

optic fibres to go along calcarine sulcus to occipital lobe

Question 21

where does the striate cortex lie?

Answer 21

above and below calcarine sulcus

Question 22

what’s either side of striate cortex?

Answer 22

Visual association cortex

Question 23

path of light through eye

Answer 23

light information coming from left hand side goes to right hand retina

Question 24

what happens to middle section the retinal sides

Answer 24

Blind spot!

Question 25

path of optic nerves from retina - distinguish path of left from right

Answer 25

nasal part of retina sends information to contralateral side. Temporal part of retina sending to ipsilateral side.

Question 26

information from left hand side is interpreted from what side of hemisphere

Answer 26

right hand side

Question 27

upper visual field goes to which bank of calcarine sulcus

Answer 27

lower bank of calcarine sulcus

Question 28

lower visual field goes to which bank of calcarine sulcus

Answer 28

upper bank of calcarine sulcus

Question 29

where does the centre of the visual axis (macula) go?

Answer 29

occipital pole

Question 30

as you go along calcarine sulcus does vision become more central or peripheral?

Answer 30

central

Question 31

how do visual field fibres get to lower calcarine sulcus?

Answer 31

inf. horn of lat ventricle | meyer's loops

Question 32

scotoma definition

Answer 32

localised patch of blindness

Question 33

anopia definition

Answer 33

refers to the loss of one of more quadrants of the visual field

Question 34

hemianopia definition

Answer 34

half of the visual field is lost

Question 35

quadrantanopia definition

Answer 35

quarter of the visual field is lost

Question 36

homonymous definition

Answer 36

visual field losses are similar for both sides

Question 37

heteronymous definition

Answer 37

visual field losses are on different sides

Question 38

what happens when you cut optic nerve in one eye

Answer 38

blind in one eye | monocular blindness

Question 39

pituitary gland growth causes what

Answer 39

heteronymous hemianopia loss of crossing fibres aka bitemporal hemianopia

Question 40

optic tract damage

Answer 40

homonymous hemianopia

Question 41

optic radiation damage

Answer 41

homonymous quadrantanomia (with macula sparing)

Question 42

both optic radia damaged

Answer 42

homonymous hemianopia (with macula sparing)

Question 43

tip of occipital pole damage

Answer 43

scotoma

Question 44

what percentage of fibres goes where?

Answer 44

10% go to the lateral geniculate nucleus of thalamus

Question 45

what does pupillary light reflex test?

Answer 45

Afferent: optic nerve and tract Efferent: oculomotor

Question 46

what muscle constricts the eye? which nerve?

Answer 46

``` sphincter pupillae (circular) oculomotor short ciliary ```

Question 47

what muscles dilates the eye? which nerve?

Answer 47

``` dilator pupillae (radial) long ciliary ```

Question 48

what components are there of pupillary light reflex?

Answer 48

direct | consensual

Question 49

what is direct component?

Answer 49

light in one eye, same pupil constricts

Question 50

what is consensual component?

Answer 50

light in one eye, other pupil constricts

Question 51

how do the pupillary light fibres enter the mid brain?

Answer 51

synapses in pre-tectal area

Question 52

what sits either side of cerebral aqueduct?

Answer 52

Edniger-Westphal nucleus

Question 53

What is the Edniger-Westphal nucleus?

Answer 53

Receives ipsilateral and contralateral optic fibres Parasympathetic oculomotor nucleus Gives off pre-ganglionic fibre

Question 54

Where does the pre-ganglionic nerve from the Edniger-Westphal nucleus go to?

Answer 54

Ciliary ganglion (runs with oculomotor nerve)

Question 55

would your eyes be permanently dilated if one of your optic nerves is damaged?

Answer 55

No | Because oculomotor is intact

Question 56

would your eyes be permanently dilated if one of your oculomotor nerves is damaged?

Answer 56

Yes | Unopposed sympathetic input

Question 57

can ask about accommodation reflex

Answer 57

but not until the integrated