Special Senses Anatomy

Question 1

3 openings at the apex of the orbit

Answer 1

Superior orbital fissure
Inferior orbital fissure
Optic foramen

Question 2

Neurovascular structures passing through optic foramen

Answer 2

Optic nerve

Ophthalmic artery

Question 3

Neurovascular structures passing through superior orbital fissure

Answer 3

Motor nerves to eye - CN III, IV, VI
Branches of ophthalmic artery
Veins

Question 4

Neurovascular structures passing through inferior orbital fissure

Answer 4

Maxillary division of CN V

Question 5

Cranial nerves in the orbit

Answer 5

Optic - CN II
Oculomotor - CN III
Trochlear - CN IV
Abducent - CN VI

Question 6

Function of optic nerve in the orbit

Answer 6

Carries visual impulses

Question 7

Function of oculomotor nerve in the orbit

Answer 7

Supplies muscles going to the eye (except 2) and supplies levator muscle of eyelied

Question 8

Function of trochlear nerve in the orbit

Answer 8

Supplies superior oblique muscle

Question 9

Function of abducent nerve in the orbit

Answer 9

Supplies lateral rectus muscle

Question 10

Function of fibrous coat of the eyeball

Answer 10

Contains collagen fibres which hold structures inside the eye together

Question 11

Layers of the eyeball

Answer 11

Fibrous coat
Vascular coat
Sensory coat

Question 12

Contents of vascular coat

Answer 12

Iris
Pupil
Ciliary body
Choroid plexus

Question 13

Function of choroid plexus

Answer 13

provides nutrition to sensory layer

Question 14

Contents of fibrous layer

Answer 14

Cornea

Sclera

Question 15

What is the vitreous humor?

Answer 15

Transparent gel behind the iris that helps cushion the retina

Question 16

Function of the cornea

Answer 16

Transparent so allows light rays to enter the eyeball

Question 17

Function of the sclera

Answer 17

Gives attachment to muscles moving the eyeball

Question 18

Function of ciliary body

Answer 18

Suspends the lens and produces aqueous humor

Question 19

Function of iris

Answer 19

Controls diameter of the pupil and therefore the amount of light rays entering the eyeball

Question 20

What structures does the retina contain that allow us to see?

Answer 20

Rods and cones

Question 21

What is the aqueous humor?

Answer 21

Watery fluid anterior to the lens that helps to maintain intraocular pressure

Question 22

Function of the intrinsic ocular muscles

Answer 22

Control pupil diameter and help alter lens curvature

Question 23

Function of the extrinsic ocular muscles

Answer 23

Move the eye

Question 24

Intrinsic muscles of the eye

Answer 24

Ciliaris
Constrictor pupillae
Dilator pupillae

Question 25

Innervation of ciliaris and constrictor pupillae muscles

Answer 25

Parasympathetic via oculomotor nerve

Question 26

Innervation of dilator pupillae

Answer 26

Plexus around the blood vessels

Question 27

Straight extrinsic muscles

Answer 27

Medial rectus Lateral rectus Inferior rectus Superior rectus

Question 28

Oblique extrinsic muscles

Answer 28

Superior oblique | Inferior oblique

Question 29

Where do the recti muscles arise from?

Answer 29

Apex of the orbit, from an annular fibrous ring

Question 30

Where does the superior oblique arise from?

Answer 30

Roof of the orbit, posteriorly

Question 31

Where does the inferior oblique arise from?

Answer 31

Floor of the orbit, anteriorly

Question 32

What muscle acts to elevate the eyelid?

Answer 32

Levator palpebrae superioris

Question 33

Actions of medial rectus

Answer 33

Adduction

Question 34

Actions of lateral rectus

Answer 34

Abduction

Question 35

Actions of superior rectus

Answer 35

Elevation, adduction, intorsion

Question 36

Actions of inferior rectus

Answer 36

Depression, adduction, extorsion

Question 37

Actions of superior oblique

Answer 37

Intorsion, depression, abduction

Question 38

Actions of inferior oblique

Answer 38

Extorsion, elevation, abduction

Question 39

Innervation of the lacrimal gland

Answer 39

Parasympathetic from facial nerve

Question 40

Tears drain through

Answer 40

punctae on medial side of each eyelid, then into the lacrimal sac

Question 41

Lacrimal sac drains through

Answer 41

nasolacrimal duct into inferior meatus

Question 42

Middle and inner ear are housed by

Answer 42

petrous part of temporal bone

Question 43

CN VII and VIII enter the skull through the

Answer 43

internal acoustic foramen

Question 44

Muscles in the middle ear

Answer 44

Tensor tympani | Stapedius

Question 45

Ear ossicles joint type

Answer 45

Synovial