HNS 4

Question 1

function of the meatus

Answer 1

vascularised and warms and humidies air and traps pathogens

Question 2

what nerves innervate the nasal cavity?

Answer 2

I, V, VII, T1 sympathetic nerves of spinal cord

Question 3

what is the function of olfactory (I) nerve in the nasal cavity

Answer 3

olfaction (smell)

Question 4

what is the function of trigeminal (V) nerve in the nasal cavity

Answer 4

general sensation
V1: anterior region
V2: posterior region

Question 5

what is the function of facial (VII) nerve in the nasal cavity

Answer 5

glands via parasympathetic fibres

Question 6

what is the function of sympathetic nerves from T1 of spinal cord in the nasal cavity

Answer 6

vascular smooth muscle

Question 7

what vessels supplies the nasal cavity

Answer 7

internal carotid artery and branches of external carotid

Question 8

why is there a risk of infection from the nasal cavity to the cranial cavity

Answer 8

some blood vessels that drain the nasal cavity pass through the cavernous sinus-> cranial cavity

Question 9

what are the paranasal sinuses and their innervations

Answer 9

V1: frontal sinuses
V1 and V2: ethmoid air cells and sphenoid sinuses
V2: maxillary sinus

Question 10

function of paranasal sinuses

Answer 10

-air-filled spaces (with some being mucus secreting) that decreases weight of skull, acting as crumple zones, increasing resonance of voice + humidifying and heating inhaled air

Question 11

how does the facial nerve runs through the ear?

Answer 11

runs through the middle ear from internal acoustic meatus and continues into the opening to nasal cavity, via pharyngotympanic tube (has branch in middle ear called chorda tympani for a2/3 (t) that goes down and joins facial nerve out o& stylomastoid foramen)

Question 12

where does the facial nerve originate?

Answer 12

lateral surface of brainstem between pons and medulla

Question 13

motor functions of facial nerve (large)

Answer 13

-muscles of facial expression
-stapedius (ear)
-posterior belly of digastric muscle
-stylohyoid

Question 14

sensory and motor functions of facial nerve (smaller-intermediate)

Answer 14

-taste in A2/3 tongue
-hard + soft palates
-general from external acoustic meatus (ear canal) and deeper parts of auricle
-(motor)parasympathetic glands of nasal cavity (lacrimal, mucous) and sublingual and submandibular glands

Question 15

function of chorda tympani (branch of facial nerve)

Answer 15

taste of anterior 2/3 of tongue
parasymp innervation to sublingual and submandibular glands

Question 16

origin of all rectus muscles

Answer 16

common tendinous ring

Question 17

what nerve innervates the rectus muscles

Answer 17

Oculomotor (III) except lateral rectus (abducens CN VI)

Question 18

what are the muscles of the eye

Answer 18

-rectus (superior, inferior, lateral, medial)
-obliques (superior, inferior)
-levator palpebrae superioris

Question 19

what innervates inferior oblique

Answer 19

Oculomotor III

Question 20

origin of inferior oblique

Answer 20

orbital surface of maxilla

Question 21

what innervates superior oblique

Answer 21

Trochlear (IV)

Question 21

origin of superior oblique

Answer 21

body of sphenoid

Question 22

origin of superior oblique

Answer 22

body of sphenoid

Question 23

describe the isolated muscle actions for each muscle of the eye

Answer 23

LR: laterally
MR: medially (towards nose)
SR: superior medially
IR: inferior medially
IO: superior laterally
SO: inferior laterally (down and out muscle)

Question 24

how do we test eye muscle actions clinically for superior rectus? What about superior oblique?

Answer 24

-ask patient to look outwards and then ubpwards showing an abducted movement -ask patient to look inwards than downwards showing adducted movement

Question 25

how do we test eye muscle actions clinically for superior rectus? What about superior oblique?

Answer 25

-ask patient to look outwards and then ubpwards showing an abducted movement -ask patient to look inwards than downwards showing adducted movement

Question 26

function of oculomotor III nerve on the eye

Answer 26

innervates number of muscles that move the eye and contain autonomic fibres that alters thickness of lens and pupil size

Question 27

what ganglion allows parasympathetic and sympathetic changing on pupil size and lens thickness

Answer 27

ciliary ganglion of oculomotor nerve (III)

Question 28

what supplies lacrimal gland

Answer 28

sensation: lacrimal nerve of opthalmic division V1 motor: facial nerve

Question 29

what are all the nerves of the orbit?

Answer 29

vision: optic (II) lens thickness + pupil size: oculomotor (III) ciliary ganglion movement of eye: III, IV, VI, oculomotor, trochlear and abducens lacrimal gland: V1 (s) and VII (pm)

Question 30

what nerves are found in the cavernoius sinous

Answer 30

superior -> inferior -oculomotor nerve iii -trochlear nerve iv -abducent nerve vi -opthalmic division of trigeminal nerve v1 -maxillary division of trigeminal nerve v2

Question 31

what is inferior to the cavernous sinus?

Answer 31

sphenoidal (paranasal) sinus

Question 32

function of the lacrimal system

Answer 32

production and (medial) movement + drainage (via nasolacrimal duct) of fluid from surface of eye