Head and Neck Week 3 - wet room Flashcards
what 7 bones make up the orbit of the eye?
Superior margin: frontal bone and sphenoid
Inferior margin: maxillary bone, palatine and zygomatic
Medial margin: ethmoid, lacrimal bone, sphenoid (body of) and maxilla
what are the 3 foramina at the apex of the orbit?
optic foramen
superior orbital fissure
inferior orbital fissure
what passes through the optic foramen
optic nerve
opthalmic artery
what passes through the superior orbital fissure?
III cranial nerve - oculomotor nerve
IV cranial nerve - trochlear
VI cranial nerve - abducens
opthalmic (VQ division of CNV) nerve
opthalmic veins
what passes through the inferior orbital fissure
maxillary division of CN V nerve
a
sphenoid sinus
b
frontal sinus
c
ethmoid sinus
d
maxillary sinus
what makes the floor of the orbit weak?
inferior orbital groove
what are the main contents of the orbit?
eyeballs
extrinsic ocular muscles
ligaments supporting the eye
optic nerve
branches of inferior opthalmic artry
the lacrimal (tear) apparatus
orbital fat
whata re the 3 layers of the eye?
outer fibrous layers
middle vascular layer
inner sensory layer
what makes up the outer fibrous layer of the eye?
sclera
cornea
it is a complete layer (extends all the way through)
what makes up the middle vascular layer of the eye?
choroid
ciliary body
iris
Is incomplete anteriorly. Anterior apeture (in iris) is called pupil
what makes up the inner sensory layer of the eye?
retina
is present posteriorly but anteriorly it stops short just infront of equator of the eye
what divides the eye into an anterior and aposterior segment?
crystalline lens
what is the name of the watery fluid in the anterior segment?
aqueous humour
what is the name of the gel in the posterior segment?
vitreous humour
a
ciliary body
b
lens
c
ciliary body
d
ora serreta
(anterior end of retina)
serrated junction between the retina and the ciliary body
e
fovea centralis
f
optic nerve head (he physiological blind spot)
g
optic nerve
what part of the eye produces (secretes) aqueous humour?
ciliary body
what are the intrinsic muscles of the eye?
ciliaris
constrictor pupillae
dilator pupillae
What is the location of:
ciliaris
constrictor pupillae
dilator pupillae
ciliaris - ciliary body
constrictor pupillae - pupillary border of iris
dilator pupillae - radially running muscles in iris
What is the action of:
ciliaris
constrictor pupillae
dilator pupillae
ciliaris - accommodation
constrictor pupillae - constricts pupil
dilator pupillae - dilates pupil
what is the innervation of:
ciliaris
constrictor pupillae
dilator pupillae
ciliaris - parasympathetic via cranial nerve IIIn
constrictor pupillae - parasympathetic via cranial nerve IIIn
dilator pupillae - sympathetic innervation
Is the constrictor pupillae and dilator pupillae sympathetic or parasympathetic?
constrictor pupillae - parasympathetic
dilator pupillae - sympahtetic
what produces movements of the eye?
extrinsic muscles of the eye
what are the different eye movements?
in addition there is also intort and extort and these movements occur when the head is tilted
in order ot keep the eyeballs focussed on an object the eyes rotate in the opposite direction
when the top of the eye rotates towards the nose it is called as intortion, and when it rotates away form the nose it is extortion
how many extrinsic muscles of the eye is there
6
4 have a straight course (recti)
2 are oblique
in addition the elevator of the upper eye lid is also considered as an extrinsic eye msucle even though it has no action on the eyeball itself
What is the muscle in the orbit that elevates the superior (upper) eyelid?
The levator palpebrae superioris
a
superior rectus
b
lateral rectus
c
inferior oblique
d
trochlea
e
superior oblique
f
meidal rectus
g
inferior rectus
what is the nerve innervation of the extrinsic eye muscles?
CN III (oculomotor) = MR, IR, SR, IO
CN IV (trochlear) = SO
CN VI (abducens) = LR
what is the action of the medial rectus
adduction
what is the action of the lateral rectus
abduction
what is the action of the superior rectus
elevation
adduction
intorsion
what is the action of the inferior rectus
depression
adduction
extorsion
what is the action of the superior oblique
depression
abduction
intorsion
what is the action of the inferior oblique
extorsion
elevation
abduction
what is the only muscle of the eye that does not arise form the posterior aspect of the orbit?
inferior oblique
what are the ligaments that prevent over-adduction and over-abduction of the eye?
medial check ligaments and lateral check ligaments?
what is the function of the suspensory ligament of the eye?
connect the ciliary body to the lens, holding it in place
name the branch of the internal carotid artery that supplies the orbit and the eye?
opthalmic artery
which foramina in the orbit do the opthalmic veins pass through to enter into the cavernous sinus in the cranial cavity?
superior orbital fissure
are there lymphatics in the eye?
no
what part of the orbit does the lacirmal gland lie, medial or lateral?
lateral
form which cranial nerve does parasympathetic innervation to the lacrimal gland arise?
facial nerve (CN VII)
into which meatus of the nasal cavity does it drain (via the nasolacrimal duct)
inferior meatus
what are the ossicles?
bones in mmiddle ear
malleus
incus
stapes
what type of joint is found between ossicles?
synovial joint
which ossicle is in contact with the tympanic membrane?
malleus
which ossicle is in contact with the oval window?
stapes
name 2 msucles related to the ossicles and their actions?
stapedius and tensor tympani
stabilize the stapes
Dampen loud sounds/reduce impact of loud noise. When tensed, the muscle pulls the malleus medially, tensing the tympanic membrane and damping vibration in the ear ossicles and thereby reducing the perceived amplitude of sounds
name 2 areas which the cavity of the middle ear communicates?
nasopharynx
mastoid antrum (an air space in the petrous portion of the temporal bone, communicating posteriorly with the mastoid cells) to mastoid air cells
within which part of the temporal bone does the middle and inner ear lie?
petroud part
The inner ear consists of a series of bone lines chambers called the __________. Inside the bony labyrinth lies a series of membranous chambers called the ___________________
The inner ear consists of a series of bone lines chambers called the bony labyrinth. Inside the bony labyrinth lies a series of membranous chambers called the membranous labyrinth
what is the fluid that lies within the bony labyrinth?
perilymph
what is the fluid that lies within the membranoud labyrinth?
endolymph
what is the function of the cochle and the semicircular canals?
cochlea - converts sound pressure impulses form the outer ear into electrical impulses which are passed to the brain via the auditory nerve
semicircular canals - the bodys balance organs
a
semicircular canals
b
auditory nerve
c
cochlea
d
eustacian tube
e
stapes
f
tympanic membrane
g
incus
h
malleus
i
temporal bone
through which foramen does the facial nerve exit the posterior cranial fossa? and which other cranial nerve als exits through this foramen?
internal auditory meatus
vestibulocochlear (CN VIII)
where deos the facial nerve run in relation to the middle ear?
runs in a canal (facial canal) on the medial wall of the middle ear cavity
while the facial nerve is in the middle ear it gives off the chorda tympani nerve which carries what?
parasympathetic (preganglionic) efferent fibres destined for submandibular and sublingual salivary glands, these are secretomotor
sensory fibres carrying special sense of taste and this supplies the anterior 2/3 of the tongue
lymph fluid passes through _______ lymph nodes and also through a terminal group of lymph nodes, the ____________ lymph nodes, before being reutrned to the venous circulation
regional
deep cervical
what are the deep cervical lymph nodes?
A group of lmyph nodes which are found as a linked chain of nodes around the ineral jugular vein, and within the fascia of the carotid sheath. The chain of lymph nodes may extent from the base of the skull to the root of the neck at the thoracic inlet
at the inferior end of the deep cervical chain of lymph noes, the efferent lympthatic vessels join together to form what on each side?
jugular lymph trunk
where do the efferent lymphatics from these jugular lymph trunks drain into?
on the right side - right lymphatic duct
on the lieft side - thoracic duct
name the different groups of nodes/lymphatics of the face and neck
parotid nodes
buccal
submental
submandibular
mastoid
occipital
what is the location of each of the following groups of lymph nodes in the face and scalp?
parotid nodes
buccal
submental
submandibular
mastoid
occipital
parotid nodes - on or in parotid gland
buccal - over buccinator muscle
submental - anteriorly just under mandible
submandibular - below the lower border of body of mandible
mastoid - overlie mastoid process
occipital - overlie occipital process
where do of each of the following groups of lymph nodes in the face and scalp drain lymph from?
parotid nodes
buccal
submental
submandibular
mastoid
occipital
parotid nodes - scalp around parotid gland, lateral parts of eyelids, and middle ear
buccal - cheek region
submental - anterior tongue tip, central part of the floor of the mouth and chin
submandibular - fornt of the scalp, nose lips, air sinuses - ethmoidal, frontal, maxillary; teeth, gums, anterior tongue, floor of the mouth; and efferent lymphatic form submental nodes
mastoid - middle regions of scalp and external auditory meatus
occipital - back of the scalp
what is the name of groups of lymph nodes that drain lymph form the neck?
anteiror cervical nodes
superficial cervical
retropharyngeal
laryngeal
tracheal
What is the location of the following lymph nodes in the neck?
anteiror cervical nodes
superficial cervical
retropharyngeal
laryngeal
tracheal
anteiror cervical nodes - lie along naterior jugular veins
superficial cervical - lie along external jugular vein
retropharyngeal - lie between the pharynx and the vertebral bodies
laryngeal - lie around the cricothyroid ligament
tracheal - around trachea
Where do the following lymph nodes in the neck drain lymph from?
anteiror cervical nodes
superficial cervical
retropharyngeal
laryngeal
tracheal
anteiror cervical nodes - superifical structures of anterior neck
superficial cervical - form parotid nodes, and the angle of the mandible, structures that lie at the junction between the neck, the face and the scalp
retropharyngeal - nasopharynx, auditory tube, and the upper cervical vertebral column
laryngeal - larynx and adjacent structures
tracheal - trachea and thyroid gland
efferent lymhpatic vessels from all these groups of lymph nodes carry lymph to the what?
deep cervical nodes
what ;ymph node becomes swollen in tonsilitis?
a lymph node at the junction of the IJV and common facial vein, the jugulodigastic or the tonsillar node
becomes enlarged in tonsillitis and is the commonest encountered swelling in the neck
what is bloc dissection of the neck for malignant disease
removal of lymph nodes of the anterior and posterior triangles of the neck and their associated lymph channels, together with those structures whcih must be excised in order to make this lymphatic ablation possible
it is sometimes ocmbined with en bloc removal of the primary tumour
a
posterior auricular
b
occipital
c
superficial cervical
d
deep cervical
e
parotid
f
buccal
g
submandibular
h
submental
i
deep cervical
