BB EOYS4 Flashcards
how do u check for raised intracranial pressure? [1]
opthalmascope - look for optic nerve where it enters retina (eyes are outgrwoth of brain). optic nerve gets squashed at high pressure - causes papilledema / optic discs bulge out
** what changes would be felt bc of this lesion (brown-sequard)? **
- loss of pain and temperature on right side of body below lesion (spinothalamic decussates at level of spinal cord entry)
- loss of motor movement on same side as lesion (corticospinal goes down ipsilateral side)
- loss of proprioception and vibration sense on the same side from damage (DCML has already decussated)
What are the two layers of the dura mater? [2]
- *periosteal layer** (which lines the inner surface of the bones) [1]
- *meningeal** layer which forms dural folds. [1]
which of the following will show localised pain?
corticospinal tract
anterior spinothalamic tract
posterior spinothalamic tract
lateral reticulospinal tract
medial reticulospinal tract
which of the following will show localised pain?
corticospinal tract
anterior spinothalamic tract
posterior spinothalamic tract
lateral reticulospinal tract
medial reticulospinal tract
which level of the brainstaim did you find cerebral aquaduct?
midbrain
medulla
thalamus
pons
corpus callosum
which level of the brainstaim did you find cerebral aquaduct?
midbrain
medulla
thalamus
pons
corpus callosum
describe pathway of cutaneous afferents from the face? [1]
- Cutaneous afferents from the face travel in cranial nerves and enter the trigeminal nucleus
- Post-synaptic fibres from the trigeminal nucleus decussate and run alongside the medial lemniscal fibres from the body.
- the face afferents end in the VPM thalamus (ventro-postero-medial nucleus),
which CN spans all of the brainstem? [1]
facial nerve
describe the difference in innervation from facial nerve between upper and lower muscles of face?
muscles of upper part of face - frontalis: bilateral innervation - gets innervation from both contralateral and ipsilateral motor cortex ! (upper motor neurons from L & R of brain synapse the lower motor neuron, which innervates the frontalis)
muscles of lower part of face: just contralteral innervation one upper motor neuron from L or R, travel down and decussate and synapses with lower motor neuron
which 2 arteries provide main blood supply to midbrain? [2]
which 2 arteries provide main blood supply to midbrain? [2]
basilar artery
- *- superior cerebellar artery
- posterior cerebellar artery**
choridal atery
which of the lateral spinothalamic tracts causes unpleasant quality of painfulness?
PAG
mediodorsal nuclei of thalamus
ventromedial (VM) & ventroposterior (VP) of thalamus
which of the lateral spinothalamic tracts causes unpleasant quality of painfulness?
PAG
mediodorsal nuclei of thalamus
ventromedial (VM) & ventroposterior (VP) of thalamus
which 3 reactions does the accomodation reflex test? [3]
constriction of pupils
thickening of lens (cilliary muscle constriction)
convergenece of eye balls ( CNIII: movement of eyeballs - medial rectus muscle !!)
what are the three main branches of facial nerve (VII), what type of innervation do they provide?
greater pertrosal: parasympathetic innervation to lacrimal gland (eye fluid & tears)
- *chordae typmani:**
- special sensory innervation to anterior 2/3rd of tongue;
- parasympathetic innervation to sublingual and submandibular glands
motor root: TZBMC (two zulus bit my cat); temporal, zygomatic, buccal, marginal mandibular, cervical: motor muscles of facial expression
midbrain:
what is role of:
- superior colliculi [1]
- inferior colliculi [1]
- cerebral peduncles [1]
midbrain:
what is role of:
- superior colliculi [1]
- *eye movements and visual processing**
- inferior colliculi [1]
- *auditory processing**
- cerebral peduncles [1]
- *contains tracts descending from thalamus (CST & CBT)**
Brown-Sequard Syndrome is damage to one side of spinal cord.
what paraylsis / loss of senses occurs at:
_ipsilaterally
1/2 levels below lesion ipsilaterally:
2 levels below lesion ipsilaterally
2 levels onwards below lesion on contralaterol sid_
ipsilaterally: get complete paralysis below the level of the lesion: due to blocking of corticospinal
1/2 levels below lesion ipsilaterally: complete anaethesia for 1/2 levels due to block of ispilateral spinothalamic.
2 levels below lesion ipsilaterally: loss of light touch, proprioception and vibration (due DCML)
2 levels onwards below lesion on contralaterol side: loss of pain, temp and crude touch 2 levels & below level of lesion - due to the nerves in spinothalamic tract crossing over over couple below
afferents from the face end come up through the medial lemniscus and terminate in which part of the thalamus? [1]
afferents from the body come up through the medial lemniscus and terminate in which part of the thalamus? [1]
afferents from the face end come up through the medial lemniscus and terminate in which part of the thalamus? [1]
VPM- ventro-postero-medial
afferents from the body come up through the medial lemniscus and terminate in which part of the thalamus? [1]
ventero-postero-lateral: VPL
(together they form complete somatosensory thalamus)
what is the blood supply to the medulla mainly from? [1]
- what are the 5 branches? [5]
medulla blood supply = verterbal arteries
- **anterior spinal artery
- posterior spinal artery
- posterior inferior cerebellar artery (PICA)
- anterir inferior cerebellar artery (AICA)
- basal artery**
which of the lateral spinothalamic tracts causes arousal & attention to pain?
PAG
mediodorsal nuclei of thalamus
ventromedial (VM) & ventroposterior (VP) of thalamus
which of the lateral spinothalamic tracts causes arousal & attention to pain?
PAG
mediodorsal nuclei of thalamus
ventromedial (VM) & ventroposterior (VP) of thalamus
posterior spinocerebellar tract pathway?
enters via dorsal root into dorsal horn: synapses with secondary neuron here and goes into posterior spinocerebella tract and goes up to cerebellum on SAME side (ipsilateral)
no decussation !!
Dolls eye reflex:
Afferent CN? [1]
Efferent CNs? [3]
how do u test? what is a normal reflex and abnormal reflex?
Dolls eye reflex:
Afferent CN? [1]: CN VIII
Efferent CNs? [3] CN III, CN IV, CN VI
- tested by turning head side to side
- normal reflex: head moves to right, eyes move left
- abnormal refelx: head moves to right, eyes follow
where do you find the insula? [1]
between which lobes? [2]
where do you find the insula? [1]
lateral fissure
between which lobes? [2]
frontal and temporal
what structure connexts the cranial nerve nuclei controlling eye movement and the vestibular nuclei? [1]
medial longitudinal fasiculus:
CN III, IV and VI
describe pathway of anterior spinocerebellar tract xx enjoy
afferent nerve goes in via dorsal horn. synapse with secondary afferent here
a) MOST secondary fibres decussate and go up on the contralateral side
b) BUT, some fibres: stay on same side and go up ipsilateral side
aa) the controlateral ones: go to cerebellum, where they DECUSSATE AGAIN to get back to ipsilateral side
bb) ipsilateral side goes up and stays here
net effect is that both stay ipsilateral
Rule of 4:
which 4 midline structures do you get?
what are their deficits?
what happens when have Bells palsy?
- which part of facial nerve is affected?
- what does this present as?
what happens when have stroke palsy?
- which part of facial nerve is affected?
- what does this present as?
what happens when have Bells palsy?
- which part of facial nerve is affected: lower motor neuron
- what does this present as: ipsilateral total paralysis
what happens when have stroke palsy?
- which part of facial nerve is affected: upper motor neuron
- what does this present as: contralateral lower muscles paralsis
Rule of 4:
which 4 lateral structures do you get?
what are their deficits?
describe pathway of anterior spinocerebellar tract xx enjoy
afferent nerve goes in via dorsal horn. synapse with secondary afferent here
a) MOST secondary fibres decussate and go up on the contralateral side
b) BUT, some fibres: stay on same side and go up ipsilateral side
aa) the controlateral ones: go to cerebellum, where they DECUSSATE AGAIN to get back to ipsilateral side
bb) ipsilateral side goes up and stays here
net effect is that both stay ipsilateral
what is the difference between radicular artereis and segmental medullary arteries?
Radicular arteries
Supply the areas where the nerve roots enter and exit the spine dorsally and ventrally, respectively. These arise from anterior cervical arteries in the cervical region, from posterior intercostal arteries in the thoracic region, and from lumbar arteries in the lumbar region. They gain access to the cord via the intervertebral foramina, and important do not travel as far as the midline to anastomose with ASA or PSA.
Segmental medullary arteries
These are, to all intents and purposes, just like large radicular arteries. They arise similarly from the anterior cervical, intercostal and lumbar arteries, but the key difference is that they travel to the midline and anastomose with the ASA or PSA. The largest and most noteable segmental medullary artery is the great anterior segmental medullary artery of Adamkiewicz, which arises somewhere between T9 and T12, usually on the left, and anastomoses with the ASA to reinforce it as it supplies the lumbosacral spine.
where are the lesions?
Lesion 1:
Lesion 2:
where are the lesions?
Lesion 1: Right CN II
Lesion 2: **Right CN III
if things are same = CN II lesion (afferent is ruined)
if things are different = CN III lesions (efferent ruiend)**
