Neuroanatomy 2 pages 23- Flashcards
where does the inferior oblique make the eye go?
looking up and in
where does the superior oblique make the eye go?
looking down and in
are CN3 nuclei close together? to they traverse laterally?
yes in midbrain
medially
what arteries does CN 3 travel between?
posterior cerebral artery and superior cerebellar artery
when does CN3 get trapped in herniation?
when temporal lobe uncus slips unter tentorium cerebelli
What nerves go through cavernous sinus?
CN 3, 4, V1, V2, 6
A lesion compresing CN3 externally will do what?
the parasympathetics fibers causing the pupil to dilate, it will have ptosis and extra-ocular muscle weakness
what commonly compresses CN3 that is not a herniation?
posterior communicating artery aneurysm
what are the key features of a CN3 palsy?
ptosis, mydriasis and ophthalmoplegia
what are the key feutrues of horners?
ptosis, miosis, anhidrosis
CN3 ophthalmoplegia looks like what?
down and out
diabetes damage of CN3 has what features?
ptosis and ophthalmoplegia
not miosis
CN4 originates in the posterior midbrain then it does what?
decussates behind sylvian aqueduct then circumnavigates the brainstem
what does a patient look like with a right CN IV palsy?
tilt their head to the left
defected depression of the adducted right eye
what lesion causes ipsilateral CN3 palsy and a contralateral hemiparesis?
lesion of the cerebral peduncle
A lesion of the tract near the red nucleus will result in what?
oculomotor palsy and a tremor
Midbrain damge often results in CNIII palsy plus damage to any one of the followin, what is the other symptom that matches each location- cerebral peduncle?, RAS?, red nucleus?
-contralateral hemiparesis
-coma
tremor
a lesion within the pons damaging the CN6 nuclesu will result in what? and if the nucleus of CN7 is involved? what if it involved the corticospinal tract?
- gaze palsy
- gaze palsy and facial palsy
- gaze palsy and associated contralateral hemiparesis
what nerve is commonly damaged due to incresed ICP due to its lengthy intracranial course?
CN6
how do we remember what cranial vault holes the V branches go?
standing room only
sup orbital fissure
rotundum
ovale
what are the 3 separate nuclei of the trigeminal system?
mesencephalic in midbrain
main sensory in pons
decending in medulla
a brainstem lesion affecting the descending nucleus is depicted with what pattern of sensory loss?
expanding circle
pain and temp
mesencephalic nucleus is concerned with?
proprioception
the main sensory trigeminal nucleus is concerned with what?
light touch
what is the corneal reflex afferent? efferent?
V1
VII
what might cause ptosis, ophthalmoplegia and sensory loss over V1 and V2?
cavernous sinus problems like thrombus
extra axial facial nerve lesion may cause facial paralysis with what other findings although a lesion to the actual nucleus itself won’t?
taste salivation and lacrimation
an intra-axial lesion of just pons will never cause this
does a lesion of CN7 lead to quiter sounds?
no louder sounds (hyperacusis)
what part of the tongue does CN VII taste?
ant. 2/3
a supranuclear lesion of CNVII will do what to the forehead and orbicularis oris?
spare it and let them blink
CN 7 nucleus lesion or of the nerve spare the forehead?
no- total ipsilateral facial paralysis
what type of VIII lesion are more apt to cause imbalance or veering towards the side of the lesion?
central lesions
a lesion of the pons damaging the vestibular nuclei results in what nystagmus?
vertical or horizontal/rotatory
a lesion of the inner ear labyrinth or vestibulocochlear nerve results in what nystagmus?
horizontal
a cerebellopontine angle lesion causes damage to what nerves?
CN5, 7, 8
ipsilateral deafness, vertigo, facial numbness and complete facial paralysis
Lesions of pontine usually use CN VI and VII plus damage to the following structures, what are the signs of these- basis pontis? RAS? Trigeminal system? Spinothalamic pathway?
- contralateral hemiparesis
- coma
- ipsilateral facial sensory loss
- contralateral body sensory loss
CN 9 and 10 motor fibers arise in what nucleus?
nucleus ambiguus- supply the laryngeal and pharyngeal muscles
The parasympathetic fibers of the vagus nerve arise from what nucleus?
dorsal motor nucleus
IX X an XI exit skull through where?
jugular foramen
lesions of 3 nerves can occur at the jugular foramen- what are the signs?
dysphagia
dysarthria
shoulder droop
where does the CN12 leave the medulla?
exit between the inferior olive and corticospinal tracts
CN 12 lesions deviates toward what?
the lesion
what 6 signs make up wallenburg syndrome?
- ipsi facial pain/temp
- contralateral body pain/temp
- horner’s
- ipsilateral gait
- vertigo, nausea, vomit, nystagmus(vestibular nuclei lesion)
- dysphagia and hoarseness
What are the 3 signs that make up medial medullary syndrome?
1- tongue deviates toward lesion
- contralateral loss of vibration and proprioception
- contralateral hemiparesis sparing the face
conjugate horizontal gaze from the FEF leads to what movement of what CNs?
ipsi CN 3 medial rectus
contra CN6 lateral rectus
review the path of conjugate gaze –
FEF, brainstem decuss, PRPF CN VI, MLF, CNIII, contralateral medial rectus
What’s the secrete for knowing it is a INO
paretic left medial rectus with right gaze becomes fully functional with convergence
INO has what impairments?
impaired adduction of the ipsi eye with horizontal gaze
horizontal nystagmus of the contralateral abducted eye
With a pontine lesion the gaze deviation is where?
away from the lesion with a contalateral hemiparesis
warm water in the ear causes the patients eyes to do what?
eyes to drift in opposite direction with fast beating nystagmus towards the irrigated ear
cold water in the ear makes the patienseyes to do what?
drift towards the irrigated ear with fast beating nystagmus in the opposite direction
Is nystagmus present in a comatose patient with an intact brainstem?
no
Does COWS apply to the comatose patients?
NO!!!! fast phase nystagmus absent in coma
what is absent in oculocephalic reflex that tells you the patient is in coma?
saccades
abnormal cold caloric testing or Doll’s head maneuver implicates what?
brainstem lesion damaging the RAS
brow sequard?
ipsi motor and proprioception
contralateral pain and temp
complete cord compression leads to what?
LMNs at first due to spinal shock, then spasticity, hyperreflexia, babinski positive and BOWEL / BLADDER. don’t forget
an expanding central cord lesion has what type of sparing?
sacral sparing and usually the dorsal columns are spared
what effects sacral roots resulting in saddle anestesia?
midline lesion of cauda equina
