Anatomy: Face, Temporal and Infratemporal Fossa Flashcards
What is the scalp?
soft tissue overlaying the skull
Layers of the Scalp:
- skin
- connective tissue (dense)
- aponeurosis
- loose connective tissue
- periosteum/pericranium
Scalp:
Aponeurosis:
- connects two muscle bellies
Blood Supply to the Scalp:
- rich vascular supply
- the most vascularised layer is the
dense connective tissue - supratrochlear, superficial temporal,
posterior auricular, occipital
Blood Supply to the Scalp:
Why do scalp lacerations bleed so profusely?
- aponeurosis when cut perpendicular
to fibres will bleed more - results in more gaping
The face is defined as
the area of the head between the scalp and the neck
Muscle Groups Surrounding the Orifices:
- three groups of muscles
- orbital, oral, nasal
Muscles of Facial Expression:
- orbicularis oculi allows closing or
scrunching of eyes - orbicularis oris allows pouting
- buccinator allows popping out of
cheek - frontalis allows eyebrow movement
- occipitalis connects but not really
part of the face - palpebral surrounds eyelids
Muscles of Facial Expression:
- procerus and nasalis acts together,
top allows scrunching, nasalis
allows/assists side to side - levator labi superioris is medial to to
zygomaticus minor - levator labi superioris alaeque nasi is
medial to the levator labi superioris - platysma is very thin
- find functions
Muscles of Facial Expression:
Muscles of Facial Expression:
Parotid Gland:
- largest salivary gland
- located anterior and inferior to the
ear - parotid gland secretes into parotid
duct - parotid duct:
- horizontally across masseter
muscle - pierces buccal fat pad and
buccinator muscle - drains into the oral
cavity/vestibule: upper 2nd molar
- horizontally across masseter
What is shown below?
Parotid gland & duct
Surface Anatomy:
3 structures that pass through the parotid gland:
- external carotid artery
- retromandibular vein
- facial nerve (motor) branches
External Carotid Artery: Branches that pass through the parotid gland:
- posterior auricular artery
- maxillary artery
- superficial temporal artery
What is aponeurosis?
flatter connection between tissues than tendons which are more dense
Retromandibular Vein: Tributaries that pass through the parotid gland:
- superficial temporal vein
- maxillary vein
Parotid Gland Vasculature:
Retromandibular vein:
- branches
- drainage
- anterior and posterior branch
- anterior branch connects with the
facial vein forming the common
facial vein which drains into the
internal jugular vein - posterior branch connects with the
superior temporal vein and the
posterior auricular vein and
eventually drains into the external
jugular vein
Retromandibular Vein:
Where does the internal jugular vein lie?
posterior to sternocleidomastoid muscle
difficult to see
common facial vein drains into the internal jugular vein
Sensory Innervation to the Face:
- skin
- trigeminal nerve
Motor Innervation to the Face:
- muscle of facial expression
- facial nerve (CNVII)
Parasympathetic innervation to the Face:
- parotid gland
- glossopharyngeal nerve (CNIX)
Label foramen from where trigeminal nerve branches emerge
Trigeminal Nerve Journey:
Trigeminal nerve emerges from the lateral surface of the pons and gives off three branches.
Ophthalmic branch from the pons passes through the superior orbital fissure to supply the orbit and them comes out of the supraorbital foramen to supply the forehead.
Maxillary branch goes through foramen rotundum and exits through the infraorbital foramen
Mandibular branch comes out of the foramen ovale and emerges through the mental foramen on mandible = sensory
Trigeminal Nerve:
Trigeminal Nerve:
insert diagram
The facial nerve emerges from and exits?
- emerges from the pons and passes
through the internal acoustic meatus - sensory branches through external
meatus? - motor part exits through the
stylomastoid foramen (behind the
ear), passes through parotid gland
and branches off)
Name 3 branches of the facial nerve.
- Chordae Tympani (parasymp and
special sensory) - Greater Tetrosal (parasymp)
- Motor Root
Name the 5 branches of the motor root of the facial nerve.
- temporal
- zygomatic
- buccal
- marginal mandibular
- cervical
Facial Nerve: Motor Root: Branches:
after exiting stylomastoid foramen, splits into five branches
Can you identify the branches of the facial nerve?
insert diagram
Bell’s Palsy:
- compression of the facial nerve as it
passes through the facial canal - injury, swelling, or ischaemia
- most common cause of unilateral
facial paralysis
Bell’s Palsy:
Glossopharyngeal Nerve:
- general sensory fibres
- motor fibres
- parasympathetic and special sensory
fibres - provides the parotid gland with
parasympathetic supply
Glossopharyngeal:
insert diagram
What effect will innervation of the facial nerve have upon the parotid gland?
Parasympathetic innervation hence will increase secretion/activity of the gland
insert
Blood Supply to the Face:
ascending pharyngeal not seen on diagram but travels deep toward pharynx
occipital runs behind the ear toward back of head
maxillary branch is very deep
superficial temporal runs upwards temples
SALFOPMS
Pulse Points:
drainage journey:
danger triangle = drainage of superior ophthalmic vein and facial vein into cavernous sinuses = risk of infection
Muscles of Mastication:
- responsible for chewing
- causes movements at TMJ
(temporomandibular joint( - temporalis, masseter, lateral
pterygoid, medial pterygoid
Temporomandibular Joint:
- formed by the articulation of the mandible with the temporal bone
- has both hinge and glid movements
- synovial joint
- BUT has atypical features:
extracapsular ligaments,
fibrocartilage articular surfaces (not
hyaline), articular disc divides into
upper and lower parts - complete….
TMJ:
Temporalis:
- function
- location
- size
- attaches***
- elevation and retraction of the jaw
- superficial
- one of the biggest
Masseter:
- function
- location
- size
- attaches***
- elevation and protrusion
- superficial
- one of the biggest
Muscles of Mastication:
Lateral Pterygoid:
- function
- attaches to
- location
- attaches
- depression and protrusion
- attaches to the
Muscles of Mastication:
Infratemporal Fossa:
- wedge-shaped
- lateral aspect
- inferior to temporal fossa
- deeper than temporal
Temporal Fossa:
- fan shaped depression
- lateral aspect
- not as deep as infratemporal fossa
Infratemporal Fossa: Contents:
Maxillary Artery:
insert diagram
- branches of the external carotid
artery - 1st part is behind the bony neck of
mandible - 2nd part is near lateral pterygoid
muscle - 3rd part is in the pterygopalatine
fossa
Branches of the Maxillary Artery:
middle meningeal artery enters skull through foramen spinosum and supplies the meninges
Inferior alveolar artery supplies lower teeth
buccal supplies the upper teeth
temporal branch runs under the zygomatic bone to supply deeper areas
Mandibular Nerve V3 Branches:
motor branch = masseter branch, lateral pterygoid, deep temporal nerves
sensory branches = buccal, inferior alveolar, lingual
chorda tympani follows lingual nerve into oral cavity
chorda tympani carries special sensory and parasympathetic fibres from the facial nerve (sensation to tongue)
