NEURO Flashcards
Define Motor Neuron Disease
Progressive neurodegenerative disorder of cortical, brainstem and spinal motor neurons
Can be lower, upper or both.
What are the subtypes of MND?
Amyotrophic Lateral Sclerosis (ALS) - Upper + Lower
Progressive muscular atrophy - Lower
Progressive Bulbar Palsy - Dysarthria, Dysphagia, Wasted and fasciculated tongue, Brisk jaw jerk reflex.
Primary lateral sclerosis - UMN + brisk reflexes + extensor plantar
What is the epidemiology of MND?
55yo
FH
What is the PC of MND?
Limb weakness
Speech disturbance
Swallowing disturbance
Behavioural changes
What are the findings on examination of MND?
LMN signs:
- muscle wasting
- fasciculations
- flaccid weakness
- hyporeflexia
UMN signs:
- spastic weakness
- extensor plantar response
- hypereflexia
Sensory exam = normal
What investigations do you need for MND?
Bloods = raised CK ESR (raised?) Anti-GM1 ganglioside AB positive EMG Nerve conduction studies (normal) MRI (cord compresion or lesions) Spirometry
What is brown sequard syndrome
Hemisection of the spinal cord
- Ipsilateral paralysis
- Ipsilateral loss of light touch + vibration
- Contralateral loss in pain + temperature
Below the lesion.
78yo man comes in post-collapse
He can follow clear one-step commands
He gets frustrated as he cannot answer questions
He is unable to lift his R hand and R leg
He has an irregularly irregular pulse
What is this? Explain.
He can follow commands but can’t speak properly = Broca’s are is affected. This is expressive dysphasia.
Brocas is on the Left hemisphere = Left sided stroke
R side weaknes = Left sided stroke
Irregularly irregular pulse implies AF which makes pts more prone to emboli hence strokes.
What is Broca’s and Wernicke’s area function
Wernicke’s is responsible for the COMPREHENSION of speech
Broca’s area is related to the PRODUCTION of speech.
What is the most significant risk factor for stroke?
HTN
HTN
HTN
(especially for intracerebrall haemorrhage)
Other RF: smokin, lipids, diabetes. (atherosclerotic stuff), poor diet, lack of exercise,
Unmodifiable RF: age, FH, ethnicity (higher in Blacks and Asians),
What is the stroke risk for AF pts?
5% per year
Can be lowered to 1% if an INR of 2-3 is acheived with warfarin.
not a question
Jerky movements during syncopes DO NOT equate to seizure
It does when its accompanied with other features (incontinence, tonic-clonic, tongue biting, cyanosis and post ictal periods)
What is the first thing you do when a patient on the wards is having a stroke?
NBM (500 SBA’s)
Aspirin and clopidogrel (laz)
What is the absolute contraindication for thrombolysis in a stroke pt?
Onset of symptoms more than 3 hours ago.
Others: (seizures, uncontrolled BP, previous intracranialbleed, LP in the last week, ischaemic stroke or head injury in the last 3 months, active bleeding somewhere else, surgery or major trauma within the last 2 weeks)
from 500sba.
Why would you check the phenytoin levels of an epileptic patient?
Phenytoin levels are mainly ordered to check compliance because its a major cause of acute attacks in known epileptics.
Diabetic patient does not respons to any sensory stimulus on the medial side of the right lower leg on neurlogical examination.
Which dermatome is affected
L4
OE a pt has 5/5 power in all muscle groups in his upper limbs and 0/5 power in all muscle groups in his lower limbs. His CN are intact
Where is this lesion?
Spinal cord
Probably a lesion transecting the cord (either thoracic or lumbar) to result in paraplegia.
OE a pt has 5/5 power in his upper limbs and 0/5 power in his lower limbs
He has a sensory loss up to the umbilicus
CN are intact
Where is the lesion?
T10 - umbilicus dermatome
This pt is paraplegic with a lesion in t10.
Sensory levels help identify the location of the lesion (could be anything from thoracic to lumbar)
Name a few important dermatomal landmarks of the trunk
c4 shoulders t4 nipples t10 umbilicus L1 pockets "L3 knee L4 to the floor"
A light is shone into a patients R eye and it constricts
When the light is shone to the L eye the L eye constricts.
When moved back to the R eye the R eye dilates
What is the diagnosis
Relative Afferent lesion
This is a swinging torch test
When moving the light from the intact left optic nerve to the damaged right optic nerve will result in reduced detection of the stimulus thus causing the right eye to abnormally dilate in response to light.
Which sign/symptom would distinguish Myasthenia Gravis from other neuromoscular junction and muscular diseases.
Fatiguability with use.
State a few differences between Myasthenia Gravis and Lamber Eaton syndrome.
MG: muscles fatigue with use
LE: muscles improve with use
MG: AchReceptor Ab
LE: Anti-VGCC Ab
MG: normal reflexes
LE: hyporeflexia
What is Lambert eaton associated with?
Small cell lung cancer
Autoimmune disease
It’s paraneoplastic subtype of myasthenia gravis.
IX: cxr - for lung cancer.
Forehead sparing indicates what?
Forehead sparing indicates an UMN lesion
Bells palsy is NON-sparing.
Female patient presents with diplopia
OE: when asked to look right the L eye stais in the midline and her R eye moves right and starts jerking
What is this?
Intranucler opthalmoplegia caused by Multiple sclerosis
Buzz: female with double vision = MS
Explanation:
There is a problem in the comunication between the abducens nerve of the R eye and the occulomotor of the Left eye. Normally these nuclei communicate via the medial longitudinal fasciculus in ordet o maintain a conjugate gaze - to keep the eyes aligned on the same spot.
If they are not aligned = double vision.
This pt has a lesion in the medial longitudinal fasciculus.
When she looks right she abducts her right eye but as the MLF is affected she is unable to direct the L eye to adduct to maintain conjugate gaze. = diplopia.
The R eye abducts fully though and develops a compensatory nystagmus for the L eye which fails to adduct.
OE: neurologist takes the patients middle finger and flicks the distal phalanx = her thumb contracts.
What is this?
Hoffman’s sign positive.
Suggests UMN disease.
What does absence of ankle jerks and upgoing plantars imply ?
Both UMN and LMN motor involvement.
Causes: stroke + superimposed peripheral neuropathy, MND, cord compression, subacute combined degeneration of the cord.
NOT MS - mixture of UMN signs, sensory loss but NEVER LMN.
Pt has an unsteady giat.
He has difficulty raising his right lef and swings it round in an arc as he walks
He also holds his right arm and wrist flexed.
What type of gait is this?
Hemiplegic gait
Typical pyramidal or UMN pattern.
As a result of a contralateral hemispheric lesion. (stroke, tumour, asbcess)
What does “-paresis” mean
weakness
-plegia = paralysis
OE a stroke pt can’t see the R lower quadrant of her visual fields.
Where is the lesion?
Left parietal lobe (google visual field defects diagram)
60yo male presents with visual problems, dizziness whcih started suddenly. He noticed he keeps bumbing into things on his right.
OE: nystagmus, dysdiadochokinesia.
Where is his stroke?
Posterior circulation
Supplies the brainstem, cerebellum (coordination) and occipital lobe.
What is Waterhouse-Friderichsen Syndrome?
bilateral adrenal haemorrhage caused by severe
meningococcal infection
What is the mx of bacterial meningitis?
3d generation cephalosporin IV
Dexamethasone IV
• Resuscitation
o Manage in ITU
o Notify public health services
How do you differentiate between the different types of meningitis on LP results?
o Bacterial meningitis: • Cloudy CSF * • High neutrophils • High protein • Low glucose **
o Viral meningitis:
• High lymphocytes
• High protein
• Normal glucose **
o TB meningitis: • Fibrinous CSF • High lymphocytes • High protein • Low glucose **
Lady presents with neurological symptoms.
OE: she can stand straight when her eye are open.
When she closes her eyes she loses balance
What is this?
Positive romberg’s test indicating proprioceptive loss
not in laz’s notes
