Eye

Question 1

describe the extracranial optic pathway

Answer 1

1. converge of axons from retinal ganglion cells (RGCs) forms optic nerve
2. RGCs receive impulses from rods and cones
3. optic canal
4. along middle cranial fossa

Question 2

describe the intracranial optic pathway

Answer 2

1. in middle cranial fossa, optic nerves join to form optic chiasm
2. fibres from medial halves cross to contralateral optic tract
3. fibres from lateral halves remain ipsilateral
4. optic tracts travel to lateral geniculate nucleus in thalamus
5. fibres synapse

Question 3

describe bauman’s loop

Answer 3

• carries fibres from superior retinal quadrants
• travels through parietal lobe
• corresponds to inferior visual field quadrants

Question 4

describe meyers’ loop

Answer 4

• carries fibres from inferior retinal quadrants
• travels through temporal lobe
• corresponds to superior visual field quadrants

Question 5

what would be the effect of damage to left optic nerve?

Answer 5

no vision in left eye

Question 6

what would be the effect of damage to optic chiasma?

Answer 6

loss of vision of temporal visual fields

hemianopia

Question 7

what would be the effect of damage to left optic tract?

Answer 7

• loss of vision of temporal field of left eye

- loss of vision of nasal field of right eye

Question 8

what would be the effect of damage to left Meyers’ loop?

Answer 8

• loss of vision in superior nasal field of left eye

- loss of vision in superior temporal field of right eye

Question 9

what would be the effect of damage to left Bauman’s loop?

Answer 9

• loss of vision in inferior temporal field of right eye

- loss of vision in inferior nasal field of left eye