week 5 Flashcards
(103 cards)
1
Q
What is benign proxysmal positional vertigo?
A
Most common cause of peripheral vertigo
- caused by post trauma or post viral infection
- treat with Dix-hallpike technique usually done by PT
2
Q
What is the clinical pearl for Nodularis Chroniculas helices?
A
Looks like basal cell carcinoma
very painful
benign
3
Q
What is the treatment for a Cholesteatoma?
A
Surgery is almost always indicated
- caused bone erosion and ST destruction
- it is a soft ball of keratin
4
Q
Dysfunction of what muscle or nerve can lead to otitis media?
A
Levator veli palatini- by CN10
- causes auditory tube dysfunction
5
Q
Do TM turn red after crying?
A
yes
6
Q
Should sinusitis typically be treated with antibiotics?
A
No about 4% of plp with sinusitis should be antibiotics
- usually inflammatory not infectious
7
Q
What is the most common clinical course of MS?
A
Relapsing and remitting episodes of neuro deficites during variable intervals of time
- as the disease progresses you have less frequency of episodes as deterioration sets in
8
Q
What causes MS lesions?
A
cellular immune response that is inappropriately directed against the components of myelin
9
Q
What are MS plaques?
A
Many, well-circumscribe, depressed, glassy and gray tan irregular shaped lesions
Commonly found
- near lateral ventricles
- optic nerve
- brainstem ascending and descending fiber tracts
- cerebellum
- spinal cord
10
Q
What role does oligodendrocytes play and where?
A
In CNS
- Making and maintenance of myelin
- defects in either making or degradation leads to pathology
11
Q
What is the composition of myelin?
A
70% lipids and low protein
- Cholesterol, galactolipid, and total phospholipid
12
Q
What makes up galactolipid?
A
Sulfatide and cerebroside
13
Q
What are plasmalogens made up of?
A
Ethanolamine phospholipids
14
Q
What are the proteins that are found in Myelin?
A
Myeline basic protein- you can live without it but will lead to defective myelin
Proteo lipid protein
- transmembrane protein in the CNS
- binds to itself so that we can have multiple layers around an axon
15
Q
What is needed for learning new skills?
A
Myelin
16
Q
Are demyelinating diseases mainly acquired or inherited?
A
acquired
- Dysmyelinating are inherited
17
Q
What is charcot marie tooth disease?
A
Dysmyelinating disorder with a stereotypical gait
PMP22 gene is duplicated
18
Q
What is VCAM-1 and its significance to MS?
A
It is a endothelial anchor which binds a4b1
- which is found on immune cells
- if we stop this binding we can stop influx of immune cells into the brain and stop its attacking on the myelin
19
Q
What drugs has been shown to decrease new lesions in MS?
A
Tysabri (natalizumab) acts on the VCAM-1/a4b1 binding pathway
20
Q
What is the MOA of Ocrelizumab?
A
Antibody which binds CD20 on B-cells to prevent overactive immune response in MS
21
Q
What are the anterior circulation arteries?
A
MCA
ACA
Lenticulo- striate artery
22
Q
What are the posterior circulation arteries?
A
Anterior spinal artery
Basilar artery
PCA
Vertebral artery
23
Q
Common characteristics of MCA stroke?
A
Effects the lateral part of the brain which is the face and upper extremities more than the LE
- Contralateral sensory and motor deficit
- Can if left sided cause Temporal (wernicke’s) or frontal (Broca’s) aphasia
- Look at lesions (Ipsilateral gaze deviation)
- Hemineglect if in non-dominant usually right side
24
Q
Common characteristics of ACA stroke?
A
Effects the middle part of brain
- motor and sensory of LE’s (contralateral)
- More likely to have behavior changes
- relatively rare
25
What are the common characteristics of a lenticulostriate stroke? aka lacunar stroke
Affects the striatum, internal capsule and other deep structures
- Lack of cortical signs
- commonly 2' to HTN
26
What is considered cortex?
frontal, parietal, temporal and occipital lobes
27
What is considered subcortex?
```
internal capsule
thalamus
brainstem
cerebellum
basal ganglia
```
28
What are cortical signs?
Gaze preference or gaze deviation
Visual field deficits
Visual and spatial neglect
Expressive and receptive aphasia
29
Where is the lesion in a pure motor stroke?
Posterior limb of the internal capsule
30
Where is the lesion in a pure sensory stroke?
thalamus
31
What are some characteristics of vertebral stroke?
Supplies the inferior cerebellum and lateral medulla
- Cerebellar dysfunction
- -----> ataxia, nystagmus, V, blurred vision, vertigo, postural instability
32
What is seen on patients with a Wallenberg syndrome?
numbness on one side of the face and opposite side of hte body due to ipsilateral cranial nerves and damage to STT.
33
What are some characteristics of Basilar strokes?
Pons, medulla, and midbrain
- corticospinal/bulbar
- ocular cranial nerve nuclei
- paramedian pontine reticular formation
Causes: gaze problems, hemianopsia and miosis
One of the few that causes LOC
Can cause LOCKED IN SYNDROME
34
What are some characteristics of a posterior cerebral stroke?
It supplies the occipital and visual cortex
- leads to homonymous hemianopsia of contralateral visual field
- non-dominant may cause neglect
35
What are some risk factors for intracerebral skroke?
HTN, ETOH, tobacco, DMD, increasing age and male
| -more associate deep structures, brainstem and cerebellum
36
What is the thunder clap HA significant for?
Subarachnoid hemorrhage caused most of the time by trauma
| - can present with N, V, stiff neck photophobia, LOC,
37
What is the single most important risk factor for a stroke?
age
| try keep blood pressure under 140/90
38
What is TPA and some characteristics of it?
It enhances plasminogen to plasmin by binding fibrin and initiates fibrinolysis
39
Primary motor cortex has what big layer?
5
| filled with Betz cells
40
What is the function of the frontal eye fields?
```
Gaze control
Nystagmus
Saccades
Vestibulo-ocular reflex
Fixation and changing of fixation
Vergence
** involved in selecting visual targets of interest and ignoring others
```
41
What is PPRF and its association?
Paramedian pontine reticular formation
- involved with horizontal component of eye movements
- Ipsi 6 and contra 3--. (OPPOSITE VESTIBULO-OCULAR REFLEX)
42
What is the role of FEF in saccade?
FEF projects to contralateral PPRF then this projects to ipsilateral saccade via superior colliculus
43
What is the function of the primary motor cortex?
The execution of movement.
Force
direction
Extent and
Velocity
44
What is the function of the pre-motor cortex?
High level of coordination
More complex multi-jiont motion
***Externally driven
Ex. Respond to external stimuli. The walking symbol turns green and thus you walk across.
45
What comes from the prefrontal cortex that is a crutial input towards the pre-motor cortex?
Planning and learning
| contribution to executive function
46
What would lesions of the pre-motor cortex present with?
Unable to respond to external stimuli
- cannot plan appropriate movements
- learn new dance moves
- cant anticipate the next move
47
What is the function of the supplementary motor area?
Internal generation of motion
- thinking about complex movements
- learning to play the piano
- pitching learning to throw the ball mechanically correct
- Dancer- acting out his choreograph in his head before he hits stage
48
Lesions of the suppplementary motor cortex cause what?
Unable to suppress motor programs stimulated by visual stimuli**
- neglect of affected arm
- Reduction of internally driven movements
49
What are some function of the BG?
Allowing action to occur
Information contributing to the choice
- phone and friend waving scenario
50
What is the striatum made up of?
Putamen- limb movement
| Caudate- Eye movement
51
What does the striatum project onto and how so?
Onto the pallidum (GPe/GPi and SNr)
| Via convergence of spinal neurons
52
SCn lesions are associated with what symptoms?
Resting tremor
Hypo/bradykinesia
shuffling gait
Lead pipe and cogwheel rigidity
53
Hemiballismus is associated with a lesion where?
Contralateral lesion
lacunar stroke
sudden wild flailing
54
What disease is associated with chorea and where is the lesion?
Huntington disease
| Striatum of BG
55
What is the functionality of the spinocerebellum and where is it located?
Vermis and paravermis
Its purpose is to carry out motor execution
- stance, posture, gait and visceral functions
- Reaching and grasping
56
What is the functionality of the cerebrocerebellum and its location?
It is located on the hemispheres of the cerebellum
Post: language and executive function
Ant: Spatially and temporally complex movements requiring coordination between muscles
- very important for timing and dancing, writing and playing a musical instrument
57
What is the functionality and location of the vestibulocerebellum?
Nodulus and flocculus
| Balance and eye movements
58
What is the function of the cerebellum?
Correcting or preventing motor mistakes
Ensuring smooth and accurate movements
Learning new motor skills
Aides in cordination and balance
59
What are the inputs to the cerebellum called? Give example
Efference- Copies of of signals dropped off as signals from our cortex travel down. This updates the cerebellum on our next move. Reason why we cant tickle ourselves.
Reafference- Sensory info from periphery about motions actually occurring. Thus, we can identify unexpexted conditions.
Ex. We are walking out side walk and texting but the side walk abruptly ends and turns to sand. The output or efferent are telling the body we are walking our concrete but the reaffence tell the body this is incorrect and that it is actually sand, we should correct!
60
What are the deep cerebellar nuclei?
```
"Don't Eat Greasy Foods" (lateral to medial)
Dentate
Emboliform
Globose
Fastigial
```
61
How does the cerebellum receive input from the cortex and where from?
Contralateral
| Via middle cerebellar peduncle
62
Proprioception from the body travels through what and on what side to get to the cerebellum?
Ipsilateral
| Inferior cerebellar peduncle
63
How about output to the cortex, where and by which structure?
contralateral cortex
| Via superior cerebellar peduncle
64
Stroke to the lateral cerebellum would result in damage to which functions?
Affect voluntary movement of extremities
| Fall towards lesion
65
Lesions of the medial cerebellum result in what?
Trucal ataxia- wide-based gait
Nystagmus
Head tilting
Axial and proximal limbs affects
66
What is the basic of cerebellum circuit of cells?
Granule/climbing fibers--> purkinje cells--> DCN
| - of note the Purkinje are inhibitory on the DCN and everything else is positive
67
What are the importance of climbing fibers?
Helps detect errors in motion from Inferior cerebellar peduncle
- originate from the inferior olive
68
Where do the olives receive input from?
Parvocellular red nucleus
reticular formation
spinal cord
69
Ipsilateral input from the inferior cerebellar peduncle?
Dorsal and rostral spinalcerebellar tracts
Cuneocerebellar tract- arms
vestibular tract and nuclei
70
What are some deficits of the spinocerebellum?
inability to adapt to changed circumstances
71
What controls the emotional facial movements of the muscles of facial expression?
Cingulate
- Contralateral lower and bilateral upper
- more supplied by ACA
- in MCA stroke then you can have weakness of lower contralateral facial expressions but you can have full movements with emotions- like laughing.
72
What does the rubrospinal tract control?
Movement of big muscles like arms
73
What is the Decorticate position?
Upper extremities in flexion
LE in extension
Means brain stem centers are working but we DONT have MODULATION of those centers from corticospinal tract
74
What is Decerebrate posturing?
All limbs in extension even head
| Now Rubrospinal tract is lost and NO MODULATION of the vestibulo or reticulo spinal tracts is happening
75
What happens when you loose your vestibulo and reticulos spinal tracts?
Flaccid paralysis and death
76
What is the function of the Vestibulospinal tract?
Medial: Regulates bilaterally the head position
Lateral: Activated antigravity muscles in limbs
77
What is the function of the reticulospinal tract?
Coordinates bilateral movements of trunk and proximal limbs.
78
What are the 2 nuclei of the reticulospinal tract?
Pontine reticular formation
| Medullar reticular formation
79
What are the nuclei of the vestibulospoinal tract?
Medial and lateral vestibular nuclei
80
What is the purpose of the Medullar reticular formation?
Inhibits Gamma motor neurons
| Excited by the Cortex
81
What is the purpose of the pontine reticular formation?
Excites Gamma motor neurons
| Inhibited by the cortex
82
What is a cause of hypertonia?
Loss of inhibition of the Gamma MN via both the medullar and pontine RF
83
What are some ways to increase tone?
Increase alpha MN via descending tracts
| Indirectly via Increase Gamma MN
84
What is the mechanism of postural tone?
Tonic activity of the Alpha MN, usually by physiological extensors
85
How about the MOA of postural adjustments on the fly? Say getting up from out of the chair?
Anticipatory input from the reticulospinal tract
| Feedback from the vestibulospinal tract
86
What are the vestibulocollic reflexes and vestibulospinal reflexes and what do the innervate?
Both Alpha and Gamma MN
- Acts on neck muscles and adjusts head
- acts to adjust limbs
87
Is it likely to have a lesion in the pyramidal tract only?
No
hard to have a lesion here without effecting the close by rubrospinal and reticulospinal
- but you would lose fine voluntary movements of hands
88
What would you expect with a spinal cord transection?
No flexes
| Flaccid
89
What would you expect about 2 months after loss of UMN?
denervation sensitive of receptors on motorneurons increases
- hypertonia and hypereflexia
90
Lesion in the internal capsule?
Initial weakness- spinal shock
- babinski
- spasticity--> Hypertonia/reflexes
- clonus
- Clasp knife
91
What the net affect of increase gamma?
Increased tone
| Both UMN, Rubrospinal and reticulospinal play a role
92
what are some characteristics of LMN lesions?
Fasiculations
Flaccid
Fibrillations
93
What is proprioception involved with?
Other body sensory receptors and the vestibular system
| - info from body eye and inner ear
94
What are some characteristics of muscle spindles?
They are intrafusal muscle fibers
- they run parallel to extrafusal muscle fibers
1. when stretched then send signals to the dorsal horn via afferents- stretching causes depolarize
2. this activated both gamma- intrafusal (inside spindle) and alpha motor fibers (extrafusal) to get stimulated and contract.
3. Decreased firing of spindle AFFERENT
- tonically active at rest= TONE
95
what role do UMN play on gamma motor neurons?
They inhibit them
| Gamma MN are inhibitor
96
What does a LMN lesion cause and how?
Flaccid due to damage of alpha MN
| could also be cause by reduced efferent of Gamma
97
What is the function of the Golgi tendon organs or GTO?
Detect muscle tension
- when the tension gets to high it relaxes the muscles
- excite inter neurons that inhibit alpha motor neuron
- respond to changes in muscle force
98
What is clasp-knife reflex?
Caused by hypertonia of extensor muscles (UMN lesion)
- Passive movement by another person of limb causes stretch reflex and one to increase tone in extensors.
- with increased applied force it releases abrubtly
99
What is gamma rigidity?
Increased excitatory or decrease inhibitory (UMN lesion)
- increased contraction of Gamma MN
- dependent on stretch reflex pathway
100
What is alpha rigidity?
Increased excitatory or decrease inhibitor of alpha MN and increase extrafusal fiber contraction
- independent of stretch pathway
- think lead pipe (smooth generation of resistance)
- When combined with tremor- Cog-Wheel
101
How does the withdrawal reflex made possible?
Reciprocal inhibition
| - inhibits via interneurons that extensors
102
Crossed extensor reflex?
Stronger stimuli produce greater flexion and shorter reaction times
103
What is unique to central pattern generators?
The entire action pattern must be completed in its entirety
