Week 11 - Brain/CN Flashcards
What is CN V?
trigeminal nerve
What is CN V1?
What does the supraorbital branch innervate?
- ophthalmic
- skin of the nose and forehead
What is CN V2?
What does the infraorbital branch innervate?
- maxillary
- skin of cheek and upper lip
What is CN V3?
What does the mental branch innervate?
- mandibular
- skin of the chin and temple
What are the branches of CN V that innervate the skin of the face?
V1, ophthalmic- supraorbital branch
V2, maxillary- infraorbital branch
V3, mandibular- mental branch
What are the muscles of facial expression innervated by?
CN VII, the facial nerve
What muscle makes up the majority of the scalp?
the occipitofrontalis, frontal and occipital bellies
What are the branches of the facial nerve?
Are they sensory or motor?
- temporal, zygomatic, buccal, mandibular, cervical (to zanzibar by motor car)
- motor
What is the terminal branch of the external carotid artery?
What does it feed?
- the superficial temporal branch
- a lot of the scalp and upper face
Where do the arteries that go to the face come from?
the external carotid, except for a contribution from the ophthalmic artery
What does the infraorbital artery come from?
the maxillary artery
What does the facial artery give rise to?
- superior and inferior labial arteries
- the angular artery
- the lateral nasal artery
What does the ophthalmic artery come from?
the internal carotid artery
What branches does the ophthalmic artery give to feed some of the face?
supraorbital and supratrochlear
What is the facial vein a tributary of?
the internal jugular vein
Where does the parotid duct travel?
it leaves out of the anterior parotid gland, dives in front of the masseter muscle and pierces the buccinator muscle to open opposite the 2nd molar
Are these branches sensory, motor, or both?
V1?
V2?
V3?
V1- sensory
V2- sensory
V3- both
What are the muscles of mastication?
What are they innervated by?
- temporalis, masseter, lateral and medial pterygoid
- V3
What are the major branches that come off the maxillary artery?
middle meningeal, inferior alveolar, and sphenopalatine
What does the maxillary vein drain into?
the retromandibular vein and then into the internal jugular vein
What is the pterygoid plexus?
What does it drain into?
- a mass of venous tissue that drains the orbit, oral cavity, jaw, and cranial cavity
- the maxillary vein
What nerves does the chorda tympani connect?
Where does it travel through?
What does it do?
- the facial nerve to the lingual nerve
- the infratemporal fossa
- parasympathetic innervation to the submandibular and sublingual glands, and taste to the anterior 2/3 of the tongue
Where does the lingual nerve come from?
it is a branch off the mandibular division of V3
What vertebrae transmit the vertebral arteries?
C1-C6 (not usually C7)
Where do the sensory branches of the cervical plexus exit from?
What are these branches?
- Erb’s point
- lesser occipital, great auricular, transverse cervical, and supraclavicular
What things are in the superficial fascia?
- platysma
- external jugular
- anterior jugular
- superficial (sensory) nerves from the cervical plexus
What are the layers of the deep fascia?
What is contained within each layer?
- investing layer- encases the SCM and trapezius
- muscular layer of the pretrachial fascia- encases the infrahyoid muscles
- visceral layer of the pretrachial fascia- wraps around the viscera (larynx, esophagus, thyroid, etc)
- prevertebral fascia- encases the deep muscles of the neck
- carotid sheath- encases the common carotid, CNX (vagus), and internal jugular vein
What innervates the SCM and trapezius muscles?
CN XI, the spinal accessory nerve
What are the suprahyoid muscles?
digastric (anterior and posterior bellies), stylohyoid, mylohyoid, and geniohyoid
What are the infrahyoid muscles?
thyrohyoid, sternothyroid, sternohyoid, and omohyoid (superior and inferior bellies)
What innervates the infrahyoid muscles?
the ansa cervicalis, a motor nerve loop off the cervical plexus
What lives between the anterior and middle scalene?
the brachial plexus and subclavian artery
What structures does the vagus nerve run between?
the common carotid and the internal jugular
Where does the phrenic nerve live in relation to the scalene muscles?
anterior to the anterior scalene
At what vertebral level is the superior cervical ganglion?
about C2
At what vertebral level is the inferior cervical ganglion?
What is special about it?
- C8 nerve
- this fuses with the T1 ganglion to make the stellate ganglion
On top of what structure does the ansa cervicalis live?
the external jugular vein
Which carotid has branches in the neck?
the external carotid
What is the carotid body innervated by?
the vagus (CN X) and glossopharyngeal (CN IX) nerves
What are the major branches of the external carotid?
- superior thyroid
- lingual
- facial
- maxillary
- superficial temporal
What are the major branches of the subclavian?
- vertebral
- internal thoracic
- thyrocervical trunk
What arteries supply the thyroid?
Where does each come from?
- superior thyroid- from the external carotid
2. inferior thyroid- from the subclavian via the thyrocervical trunk
What are the veins that drain the thyroid?
Where does each drain into?
Which is a midline structure?
- superior thyroid- the internal jugular
- middle thyroid- the internal jugular
- inferior thyroid- left brachiocephalic (midline)
What are the superficial lymph nodes in the neck?
What structure do they run along with?
- occipital, retroauricular, mastoid, parotid, and anterior/lateral cervical nodes
- the external jugular
Along what structure are the deep cervical lymph nodes traveling?
the internal jugular
What does the neurocranium contain?
What does the viscerocranium contain?
- the brain, CNS, and meninges
- most of the organs (eye, tongue, etc)
What are the layers of the scalp?
Skin Connective tissue Aponeurosis (or galea aponeurotica) Loose CT Pericranium
What innervates the scalp?
Anterior scalp- supraorbital, from V1
Lateral scalp- auriculotemporal, from V3
Posterior scalp- greater occipital, from C2 dorsal ramus
What does the falx cerebri do?
it divides the 2 hemispheres
What does the diaphragma sella do?
it is a dural reflection that covers the pituitary fossa
Between what things does the middle meningeal artery run?
What does the middle meningeal come from?
- between the dura and the skull
- the maxillary artery
Where does the cavernous sinus live?
on either side of the pituitary
What things meet at the confluence of the sinuses?
the superior sagittal sinus, transverse sinuses, and straight sinus
What connects the anterior and posterior circulations of the brain?
the circle of Willis
Where does the anterior circulation for the brain come off of?
The posterior?
- anterior: from the middle cerebral arteries
- posterior: from the vertebral arteries
What makes CSF?
What absorbs it?
- choroid plexus in the ventricles
- arachnoid granulations
Ciliary Ganglion: Where is it located? Preganglionic route? Postganglionic route? Target organs?
location- orbit
preganglionic- CN III, inferior branch
postganglionic- short ciliary nerves CN V1
target- ciliary muscles and sphincter pupillae of the iris
Pterygopalatine Ganglion: Where is it located? Preganglionic route? Postganglionic route? Target organs?
location- pterygopalatine fossa
preganglionic- CN VII, greater petrosal nerve
target - lacrimal gland
Submandibular Ganglion: Where is it located? Preganglionic route? Postganglionic route? Target organs?
location- oral cavity
preganglionic- CN VII, chorda tympani
postganglionic- lingual nerve, CN V3
target- sublingual and submandibular glands
Otic Ganglion: Where is it located? Preganglionic route? Postganglionic route? Target organs?
- location: infratemporal fossa
- preganglionic: CN IX, tympanic nerve to lesser petrosal nerve
- postganglionic: auriculotemporal nerve, CN V3
- target: parotid, buccal, and lingual glands
CN I aka?
Target?
Sensory, motor, or both?
- olfactory
- nasal cavity
- sensory
CN II aka?
Target?
Sensory, motor, or both?
- optic
- eye
- sensory
CN III aka?
Target?
Sensory, motor, or both?
- oculomotor
- ciliary muscle, sphincter pupillae, and all external eye muscles besides superior oblique and lateral rectus
- motor
CN IV aka?
Target?
Sensory, motor, or both?
- trochlear
- superior oblique muscle (eye)
- motor
CN V aka?
Target?
Sensory, motor, or both?
- trigeminal
- sensory: face, sinuses, teeth, orbit, oral cavity, dura mater
- motor: muscles of mastication, tensor tympani, tensor veli palatini, mylohyoid, anterior belly of the digastric, etc
- both
CN VI aka?
Target?
Sensory, motor, or both?
- abducent
- lateral rectus muscle
- motor