Neuro Flashcards
(136 cards)
Which lobe of the brain is responsible for voluntary motor function?
Frontal lobes
Which lobe of the brain is responsible for language and calculation?
Parietal lobes
Where is the primary sensory cortex?
Post-central gyrus, parietal lobe
Where is the primary motor cortex?
Pre-central gyrus, frontal lobes
Where is the primary visual cortex?
Occipital lobes
What are the basal ganglia responsible for?
Motor refinement
Modulation of cognitive and emotional responses
What three sections make up the brainstem?
Midbrain
Pons
Medulla
What is the bloody supply to the circle of willis?
2x vertebral arteries
2x internal carotid arteries
A clot in which artery would cause locked-in syndrome?
Basilar artery
At which level does the spinal cord terminate and become the caudal equina?
L1-2
What functions are carried within the dorsal columns?
Fine sensation, vibration and proprioception
What functions are carried within the spinothalamic tracts?
Pain, temperature and crude touch
Where do the dorsal column and spinothalamic tracts decussate?
Dorsal column tracts- decussate in medulla oblongata
Spinothalamic tracts decussate lower in the spinal cord
What is the neurological pattern of GBS?
Peripheral neuropathy- polyradiculopathy with no involvement of brain or spinal cord
Generally starts in the feet, spreading proximally to the legs, hands etc
Sensory symptoms often precede motor
Initially pain and paraesthesia -> progressive muscle weakness
Flaccid weakness and numbness
What are the clinical features of GBS?
Usually presenting following recent infection
- most commonly campylobacter gastroenteritis but can be a range of infections
Initially pain and paraesthesia affecting the feet -> spreading proximally
Followed by progressive weakness in similar pattern
Eventually central weakness -> dysarthria, extra ocular weakness, respiratory distress
LMN signs: areflexia, flaccid paralysis, ataxia
What are the triad of features which make up Miller Fisher Syndrome?
Ophthalmoplegia
Areflexia
Ataxia
How is GBS diagnosed?
Neuroimagine: NAD
Nerve conduction: slowed LMN conduction velocity
LP: elevated protein with normal cytology
Blood cultures and PCR for search for causative agent
How is GBS managed?
Regular spirometry & ABG to monitor respiratory function and need for intubation
VTE prophylaxis
IVIG for 5 days or plasma exchange if IVIG not available
NO BENEFIT of steroids
Physio, OT, neuro rehab
What are differential diagnoses for GBS?
Diabetic neuropathy- much more chronic course, prev DM, usually only sensation initially
MG- chronic, weakness varies throughout day, no pain, sensation and reflexes in-tact
Botulism- similar except DESCENDING paralysis rather than ascending, normal CSF, reflexes in-tact
Cauda equina- only affects lower body, sphincter involvement
Transverse myelitis- UMN syndrome
What is the cause of Myasthenia Gravis?
Auto-antibodies against acetylcholine receptors
What is the symptom pattern of MG?
Usually oculobulbar symptoms initially - worst in the evening
- Progressive ptosis and diplopia (horizontal mostly)
- Dysarthria, dysphagia aspiration
Progressive muscle weakness, mostly in proximal muscle groups e.g. raising arms, climbing stairs
Symptoms improve with rest
Reflexes and sensation remain in-tact
How is MG diagnosed?
Presence of AChR-autoantibodies
Nerve conduction studies: progressively decremental response on repetitive stimulation
PFTs to rule out MG crisis
How is MG managed?
1st line= pyridostigmine (AChE antagonist)
Corticosteroids
Thymectomy
Plasma exchange in crisis
What are differentials for MG?
LEMS: same but IMPROVES with repeated use rather than worsens
Botulism
Primary myopathy