Cranial nerves 3 Flashcards
how can you determine the position of an injury to the facial nerve by signs and symptoms alone
AT CEREBELLOPONTINE ANGLE
-hearing and balance problems
-ipsilateral facial muscle paralysis
-hyperacusis
-taste disturbances
-reduced lacrimal secretion
WITHIN THE PETROUS TEMPORAL BONE
-reduced lacrimal secretion
-hyperacusis
-taste disturbances
-ipsilateral facial muscle paralysis
DISTAL TO THE STYLOMASTOID FORAMEN
-ipsilateral facial muscle paralysis
-dry eye, drooling
what is the difference between central and peripheral facial palsy
CENTRAL:
-UMN lesion
-can raise eyebrows, cannot blow cheeks
muscles in upper part of face are not affected as superior division has ipsilateral connection to the cortex
PERIPHERAL
-LMN lesion
-cannot raise eyebrows, cannot blow cheeks
all output is severed as lower division is only contralateral
what does the cornea reflex test
nasociliary nerve (branch of ophthalmic nerve V1) picks up sensation-> brain stem
connected to motor nucleus of facial nerve- causes orbicularis oculi to contract
by touching cornea we close our eye
test Afferent trigeminal nerve
test Efferent facial nerve
where is the nuclei of cranial nerve IX and what are the names of the nuclei
GLOSSOPHARNYGEAL
nuclei in medulla
motor- NUC. AMBIGUUS
sensory- NUC. SOLITARIUS
what sensation does the glossopharyngeal nerve receive
GENERAL SENSATION
middle ear, oropharynx, palatine tonsil, inferior aspect of soft palate, posterior 1/3 tongue
GENERAL VISCERAL SENSATOIN
carotid sinus and carotid body
SPECIAL VISCERAL SENSATION
(taste) from posterior 1/3 tongue
what muscle does glossopharyngeal nerve supply
stylopharyngeal muscle
where is the nuclei of the vagus nerve
what are the names of the nuclei
in medulla
NUC. AMBIGUUS
NUC. SOLITARIUS (taste and general visceral)
what is nucleus solitarius a common nucleus for and why
7, 9, 10
TASTE
what is the route of the vagus
leaves brainstem, pass through jugular foramen with 9 and 10 with internal jugular vein
what is the tympanic branch
it is a branch of the glossopharyngeal and forms the tympanic plexus
it goes towards the middle ear, tympanic membrane, and mastoid air cells
what sensation does the vagus nerve receive
GENERAL SOMATIC
-from deep auricle, parts of external acoustic meatus!!
GENERAL VISCERAL SENSATION
-from laryngopharynx and larynx
what muscles does the vagus nerve supply
straited muscles of pharynx and larynx
muscles developed from 4th and 6th pharyngeal arches
what does the gag reflex test
test IX and X together
touch one and then other palatal arch with tongue blade/ cotton swab
what are the two roots of the accessory nerve
and the route of the accessory nerve
SPINAL ROOT which originates from C1-5 (spinal cord)
-passes through foramen magnum to get to cranial cavity
-merge with cranial root
CRANIAL ROOT comes off nucleus ambiguus
cranial root and spinal root merge to form accessory nerve
pass through jugular foramen and exits cranial cavity
spinal root/ spinal accessory pass in posterior triangle of neck and supply SCM and trapezius
we don’t know where cranial root goes
where is the nucleus of the hypoglossal nerve found
medulla
exit brainstem anterior to olive
enter into HYPOGLOSSAL CANAL
