Head and neck: cranial nerves II Flashcards
CN VII facial nerve: enters/ exits CNS
btw pons and medulla
CN VII facial nerve: enters/ exits skull
- internal acoustic meatus -> facial canal -> stylomastoid foramen
CN VII facial nerve: site of cell bodies
- SVE (BE): pons
- SA: geniculate ganglion
- GVE: presynaptic fibres (pons), postsynaptic (pterygopalatine and submandibular ganglia)
CN VII facial nerve: list 2 main roots
- intermediate nerve (sensory, nervus intermedius)
- motor root
CN VII facial nerve: intermediate nn fibres
- GSA: sensory from ext acoustic meatus
- SA: taste ant 2/3 tongue
- GVE: parasymp secretomotor (lacrimal gland, sublingual salivary, mucous membranes of nasal cavity glands, hard and soft palate)
CN VII facial nerve: what branch supplies taste ant 2/3 of tongue
- chorda tympani (petrotrympanic fissure)
CN VII facial nerve: motor root fibres
- SVE: mm facial expression and scalp, stapedius, post belly of digastric, stylohyoid mm
CN VII facial nerve: within facial canal gives what nn
- greater petrosal
- n to stapedius
- chorda tympani
CN VII facial nerve: after exiting stylomastoid foramen, it gives-
- temporofacial
- cervicofacial
- digastric branch
- post auricular
CN VII facial nerve: once entering parotid gland name branches
- temporofacial, cervicofacial both:
- temporal
- zygomatic
- buccal
- marginal mandibular
- cervical
CN VIII vestibulocochlear nerve: enters/ exits CNS
btw pons and medulla
CN VIII vestibulocochlear nerve: enters/ exits skull
- internal acoustic meatus
CN VIII vestibulocochlear nerve: site of cell bodies
- vestibular ganglion (vestibular n)
- spiral ganglion (cochlear n)
CN VIII vestibulocochlear nerve: function SSA
- vestibular n: equilibrium
- cochlear: hearing
eg. vestibular neuritis, labryinthitis, acoustic neuroma
- vestibular neuritis: inflammation of vestibular n -> compression of structures
- labyrinthitis: similar
- acoustic neuroma: tumour growth, also compression
CN IX glossopharyngeal nerve: enters/ exits CNS
medulla
CN IX glossopharyngeal nerve: enters/ exits skull
- jugular foramen
CN IX glossopharyngeal nerve: site of cell bodies
- SVE: medulla
- GVE: presynaptic (medulla), postynaptic (otic ganglion)
- GSA: inf ganglion
- GVA: sup ganglion
- SVA: inf ganglion
CN IX glossopharyngeal nerve: function- SVA
- sense of taste post 1/3 tongue
CN IX glossopharyngeal nerve: function- GSA
sensory from mucosa of:
- palatine tonsil and oropharynx
- post 1/3 of tongue
- auditory tube (pharyngotympanic), middle ear
CN IX glossopharyngeal nerve: function- GVA
- sensory from carotid body and sinus
CN IX glossopharyngeal nerve: function- GVE
- parasympathetic
- stimulate secretion of parotid salivary gland
CN IX glossopharyngeal nerve: function- SVE (BE)
- stylopharyngeus (mm from 3rd pharyngeal arch)
CN X vagus nerve: enters/ exits CNS
medulla
CN X vagus nerve: enters/ exits skull
- jugular foramen
CN X vagus nerve: sites of cell bodies
- SVE: medulla
- GVE: presynaptic (medulla), postsynaptic fibres (neurons close to/ within viscera innervated)
- GSA: sup ganglion
- GVA: sup ganglion
- SVA: inf ganglion
CN X vagus nerve: function- SVE
- constrictor mm of pharynx (except stylopharyngeus)
- intrinsic mm of larynx
- mm of palate (except tensor veli palatini)
- skeletal mm (striated) in upper 2/3 esophagus
CN X vagus nerve: function- GVE
- cardiac mm
- smooth mm of airways, digestive tract
CN X vagus nerve: function- GSA
- sensory from auricle, ext auditory meatus, dura mater in post cranial fossa
CN X vagus nerve: function- GVA
- sensation from base of tongue, pharynx, larynx, airways, heart, oesophagus, stomach, intestine (to L colic flexure)
CN X vagus nerve: function- SVA
- taste from epiglottis and palate
don’t confuse phrenic w vagus nn:
- vagus: more medial, w common carotid aa (L loops around arch of aorta)
- phrenic: btw ant/ middle scalenes
CN XI accessory nerve: enters/ exits CNS
- cranial root: medulla
- spinal root: upper spinal cord
CN XI accessory nerve: enters/ exits skull
- jugular foramen (cranial and spinal roots)
- cranial root leaves spinal to join vagus
CN XI accessory nerve: site of cell bodies
- cranial: medulla
- spinal: spinal cord
CN XI accessory nerve: function
- cranial root: mm to pharynx, larynx
- spinal root: motor to trapezius, sternomastoid mm
CN XI accessory nerve: runs in neck
- btw int carotid aa and int jugular v, obliquely to trapezius
CN XII hypoglossal nerve: enters/ exits CNS
- medulla
CN XII hypoglossal nerve: enters/ exits skull
- hypoglossal canal
CN XII hypoglossal nerve: site of cell bodies
- medulla
CN XII hypoglossal nerve: function
- motor to intrinsic/ extrinsic mm of tongue (except palatoglossus)
CN XII hypoglossal nerve: how does it run
- after hypoglossal canal runs along mandible