Neuro Flashcards
Functional divisions of the motor nerves
Somatic, branchial or autonomic
Functional divisions of the sensory nerves
Somatic, autonomic or special
Where are somatic nerves found in the embryo
Spread throughout
Where are autonomic nerves found in the embryo
Arise in the most primitive parts. No conscious control. Smooth and cardiac muscle and glands.
Define dermatome
area of skin supplied by a single spinal nerve
Define myotome
volume of muscle supplied by a single spinal cord
What function does the corticospinal tract supply
Rapid, skilled, voluntary movement
What function does the rubrospinal tract supply
Facilitates flexors, inhibits extensors
What function does the vestibulospinal tract supply
Facilitates extensors, inhibits flexors
What function does the tectospinal tract supply
Truncal reflexes from sight
What sensation do the fasciculus gracilis and cuneatus provide
Touch, vibration and conscious joint/muscle
What sensation do the spinocerbellar tracts supply
Nonconcious muscle/joint sense
What sensation does the lateral spinothalamic tract supply
Pain and temperature
What sensation does the anterior spinothalamic tract supply
Light touch and pressure
What sensation does the spinoolivary tract supply
proprioception
What sensation does the spinotectal tract supply
Spinovisual reflexes
In brown sequard at T10 you will get ipsilateral loss of
Tactile discrimatin, vibration, proprioception and spastic paralysis
In brown sequard at T10 you will get contralateral loss of
Pain and temperature and impaired tactile sense
At what level does the spinal cord stop
L1
Where does the basilar artery lie
The anterior surface of the pons
Which arteries contribute to the posterior circulation
The vertberal arteries
What does the posterior circulation supply
The brainstem, cerebellum and back of hemispheres
What supplies the lateral surface of the hemispheres
Middle cerebral artery
What supplies the median surface of the hemispheres
Anterior cerebral artery
From the internal carotid where do blood clots tend to go
The middle cerebral artery as they want to go straight
Where are the meningeal vessels
In the extradural space
Where are bridging veins
They cross the subdural space
Where does the circle of willis lie
In the subarachnoid space
Are there any vessels deep to the pia mater
No. It forms part of the blood brain barrier
What is a parenchymal haemorrhage
A intracerebral haemorrhage
Bleeding from which artery causes an extradural haemorrhage
Middle meningeal artery
Shape of an extramural haemorrhage on imaging
Convex
What causes an extradural haemorrhage
Trauma to middle meningeal artery causes bleeding between the dura mater and the brain
What causes a subdural haemorrhage
Bleeding from the bridging veins, especially in small brains. Pressure slowly builds
What is the shape of a subdural haemorrhage on imaging
Crescent shaped
What is a subarachnoid haemorrhage
Rupture of the arteries forming the circle of willis,often because of berry aneurysms
What is a thunderclap headache suggestive of
Subarachnoid haemorrhage
What is a berry aneurysm
Weakening outpouching of the circle of willis
Which stroke has death of cells in a small area, with a well defined area and no recovery
Embolic
Which stroke has a large area affected, conmpression of the internal capsule and possible complete recovery
Haemorrhagic
Anterior segment of the internal capsule
Sensory
Posterior segment of the internal capsul
Sensorimotor
The pituatry tumours are likely to affect the…
optic chiasm
Why do you get forehead sparing
Facial has bilateral supply to forehead but contralateral to the rest of the face
Define meningitis
Inflammation of the meninges
Define encephalitis
Inflammation of the brain
Define encephalopathy
Reduced level of consciousness/diffuse disease of brain substance
Define neuropathy
Damage to peripheral nerves.
Infective causes of neuropathy
Diptheria, guillan-barre, leprosy, rabies
Define mononeuritis multiplex
Inflammation and damage to 2 or more individual nerves
Infective causes of mononeuritis multiplex
HIV, leprosy, lyme, Hep A
Define polyradiculopathy
Damage to multiple nerve roots
Infective causes of polyradiculopathy
HIV and CMV/syphilis/HMV
Define myelitis
Inflammation of the spinal cord
Define meningoencephalitis
Inflammation of the brain and meninges
Clinical signs of meningeal irritation
Reduced GCS, headache, stiff neck, papilloedema. Kernigs and Brudzinskis signs
What is kernigs sign
Hip at 90 degrees, cant extend leg
What is Brudzinskis sign
Passive neck flexion= leg and thigh flexion
What is papilloedema
Swelling of the optic disc on fundoscopy
Which vertebrae are epidurals normally entered between
L3 and L4
Which vertebrae are lumbar punctures normally done between
L4 and L5 (or L3/4 or L5//S1)
Side effects of lumbar puncture
Headache, paraesthesia, CSF leak, damage to spinal cord, cerebral herniation and death
When should you CT before lumbar puncture
60+, immunocompromised, history of CNS disease, new onset, decreasing consciousness, focal neurological signs, papilloedema, atypical history
What does xanthochromia mean
Blood stained
Causes of natural immunossupression/immunocompromised
Pregnancy, diabetes, chronic alcoholics age>60
Bacterial causes of menigitis in neonates
E coli, GroupB strep, listeria monocytogenes
What gram and shape is Ecoli
Gram negative bacilli
What gram and shape is Group B strep
Gram positive cocci
What gram and shape is listeria monocytogenes
Gram positive bacilli
What gram and shape is neisseria meningitidis
Gram negative diplococcus
What gram and shape is strep pneumoniae
Gram negative diplococcus
What gram and shape is haemophilus influenzae
Gram negative coccobacilli
What is meningitis prophylaxis of contacts for influenzae
Only need prophylaxis if havent had Hib, inform public health
What is meningitis prophylaxis of contacts for pneumococcal
No prophylaxis needed, consider pneumococcal vaccine, inform public health
What is meningococcal meningitis prophylaxis of contacts
Ciprofloxacin as prophylaxis for household contacts
What is the most common cause of viral meningitis
Enterovirus
What test is used to identify viruses
PCR
Sympoms of encephalitis
Fever, headache, lethargy and behavioural change
Trismus is a symptom of tetanus, what is trismus
Lock jaw
Opsithotonus is a symptom of tetanus, what is opsithotonus
Sustained muscle contraction
Should you lumbar puncture in suspected meningitis
Normally yes but not if signs of raised intercranial pressure or sepsis or rapidly evolving rash
Define epileptic seizure
Paroxysmal event in which changes of behaviour, sensation or cognitive processes are caused by excessive, hypersynchronous neuronal discharges in the brain
Define nonepileptic seizure
Paroxysmal event in which changes of behaviour, sensation or cognitive processes are caused by mental processes associated with psychological distress
Tongue biting, head turning, muscle pain, LOC >5mins, cyanosis and postictal confusion are suggestive of which type of seizure
Epileptic
Prolonged upright position, sweating prior to LOC, nausea, pre* symptoms and pallor are signs of which type of seizure
Syncope
Pelvic thrusting, long duration, ictal crying, change in amplitude but not frequency (poorly observed normally) is suggestive of
Non epileptic seizure
First line treatment for focal epilepsy
Carbamazepine or iamotrigine
First line treatment for absence epilepsy
Valproate or iamotrigine
What is curative epilepsy surgery for refractive epilepsy
Resective surgery or hemispherectomy
What is palliative epilepsy surgery for refractive epilepsy
Tractotomy or Vagal nerve electrostimulation
At what level do the common carotid arteries bifurcate
C3-4 with internal carotid more posterior
What can lead to anastamoses in the internal carotid
Persisting embryonic vessels
Petrous ICA branches
Corticotympanic artery to the middle/inner ear and the vidian artery which can connect to ECA
When do blood clots cause the worst strokes
When it is an end artery, like the M1 segment of the middle meningeal artery
Where in the brian is effected by the worst strokes
Deep brain structures with end arterial supply like the lentiform nucleus, caudate nucleus and internal capsule
In which compartment do childhood tumours tend to be
Intratentorial
In which compartment do adult tumours tend to be
Supratentorial
What are the clinical manifestations of CNS tumour
Loss of function, seizures and raised ICP
Is temporal lobe epilepsy more likely to be caused by which grade cancer
Low grade
Define astrocytic tumour
Tumour which shows differentiation towards astrocytes
What are the two types of astrocytic tumours
Diffuse astrocytomas (Grades 2,3,4) and other eg pliocytic (grade 1)
Oligodendroma diagnostic test
Using FISH to see 1p19q deletion and IDH 1 mutant
What are rosenthal fibres suggestive of
Pilocytic ostrocytoma
Optic nerve fibre cancers
Pilocytic ostrocytomas
Medulloblastoma signs of aggression
Large cells, N-MYC and C-MYC
Medulloblastoma signs of better prognosis
Desmoplastic in infants and Wnt molecular marker
Which tumours metastasise to the brain
Lung, breast, melanoma, GI tract and kidney
What causes raised intracranial pressure
Anything which causes an mass within the cranial cavity. Trauma, stroke, infection
Where should you look to spot mass effect
Sylvian fissure and thalamus
How does the brain initially compensate for raised intracranial pressure
Reducing CSF
What will happen when the occulomotor nerve is compromised
Pupil dilation as it was the only parasympathetic supply
What is a missile head injury
Where there is penetration of the skull or brain
What is a primary head injury
Due to immediate biophysical forces of trauma
What is a secondary head injury
Presenting some time after the traumatic event
What is aerocele
Air getting into the brain
What is a contusion
A superficial bruise of the brain
What is a lasceration
A tear
What is an cut
An incised wound with a neat edge
Which type of haemorrhage is caused by damage to bridging veins
Subdural haematoma
What is a superficial haemorrhagic brain injury from
Contusion
What is a deep haemorrhagic brain injury from
Diffuse axonal injury
What does the impact of inner surface of the skull and the brain cause
Contusion
What is the result of differential movement of brain tissue
Shearing, traction and compressive stresses which damage blood vessels and axons
What is a coup
Superficial ‘bruise’ at the site of impact
What is a contrecoup
Superficial ‘bruise’ away from the site
What is a contusion
A superficial bruise of the brain
What is difffuse axonal injury
A clinicopathological syndrome of widespread axonal damage (inc brainstem)
What are retraction balls
Areas on microscopy where following traumatic axonal injury the protein has built up when azon flow was interrupted
Long term signs of traumatic axonal injury
Corpus callosum thinning, myelin pallor, frontal lobe glydeine contusion
Three causes of brain swelling
Congestive brain swelling (vasodilation), vasogenic oedema (extravasation), cytotoxic oedema (increased water)
How is congestive brain swelling caused
Lose ability to regulate blood supply to the brain, results in vasodilation
Three things which increase the risk of hypoxia-ischaemia
Hypoxia, hypotension and raised intracranial pressure
Which cells are susceptible to hypoxia-ischaemia
Large neurones (central cortex) and purkinje cells
Define traumatic brain injury
Brain injury which results in loss of consciousness
How does MS prevalence change with latitude
Nearer equator is associated with a lower risk
What is the main cause of the inflammation in MS
Activated autoreactive T lymphocytes
Which cells maintain the myelin in the CNS
Oligodendrocytes
Where is the most common site of MS
Periventricular in the brain
What is the most common cause of Brown-Sequard syndrome
MS
MS pattern 1 pathology is mediated by
Macrophages
MS pattern 2 pathology is mediated by
Antibodies
Define primary progressive MS
Disease progression from onset with occasional plateaus and temporary minor improvements allowed
Define secondary progressive MS
Initial relapsing-remitting disease course followed by progression with or without occasional plateaus, remissions and relapses
What are the two essential diagnostic criteria for MS
1) two or more CNS lesions disseminated in time and space 2) exclusion of conditions giving a similar clinical picture
What is an EP test
Measures the electrical activity of the brain and spinal cord
In MS a lumbar puncture is done, looking for which protein in the CSF
Oligoclonal IgG
What are the two phases of MS
inflammatory stage and degenerative stage
What is unusual about fatigue in MS
It is exacerbated by heat and made better by cool
Which basal ganglia diseases are “hardware problems” with something mechanically wrong
Parkinsons disease and huntingtons disease
Which basal ganglia diseases are “software problems” without something mechanically wrong
Essential tremor, dystonia and tourettes
Presentation of parkinsons
Assymetrical at first. With gradual worsening. Tremor, stiffness, dull ache joint pain, reduced arm swing, problems doing up buttons and writing smaller.
What causes rigidity
Extrapyramidal disease
What causes spasticity
Upper motor neurone disease
Three cardinal features of parkinsons disease
Brady/akinesia, tremor, rigidity
What is the walking like in parkinsons
Small stepped gait, stooped posture, reduced armswing, L>r
How do you assess a rest tremor
Hands should be at rest and limp
How do you assess an action tremor
Hold the hands straight forward
What does symmetrical action tremor suggest
Essential tremor disease
Where is the lesion to cause an intention tremor
Cerebellum
Where is the disease to cause bradykinesia
Basal ganglia
How does bradykinesia present
Decreasing amplitude and accuracy of repetitive movements
What are the three types of tremor
Rest, action, intention
What are the two common pathological signs of parkinsons disease
Lewys bodies and loss of dopaminergic neurones
How can the reduced dopamine supply to the striatum seen in parkinsons disease be imaged
DaTSCAN (innit)
What are four factors which cause cell loss in the substantia nigra
Inherited factors, environmental factors, oxidative stress and mitochondrial dysfunction
What are inherited factors which cause parkinsons
Susceptibility factors and parkinson genes
What are enviromental factors which cause parkinsons
Risk factors and toxin induced
What are the two aims of parkinsons disease treatment
Symptomatic relief through higher dopamine levels. Increase availability of dopamine, slow dopamine loss.
Anticholinergics side effects
Cognition, confusion, systemic
What is on dyskinesias
Hyperkinetic, choreiform movements whenever drugs work
What is off dyskinesias
Fixed, painful dystonic posturing, typically on feet when drugs dont work
What should you look out for signs of alongside neural conditions
Depression
Do you get incontinence in parkinsons
NO
What shouldnt be present in early PD
Incontinence, dementia, symmetry, fails
What are incontinence, dementia and magnetic gait suggestive of
Normal pressure hydrocephalus
How can normal pressure hydrocephalus be treated
A shunt to the abdomen
Huntingtons disease cardinal features
Chorea , dementia, psychiatric problems, positive family history
What is chorea
Jerky involuntary movements
Examples of psychiatric problems
Personality change, depression and psychosis
What is generalised dystonia
A syndrome of sustained muscle contraction
What is the key sign of 3rd nerve palsy
Fixed dilated pupil
Define ataxia
Loss of full control of body movements, limb unsteadiness
Three features of cerebellar disease
Ataxia, nystagmus and deficit on the same side as the cerebellar lesion
Define nystagmus
Rapid eye movements
Which cranial nerves are associated with the brainstem
3-12
What is the reticular activation system
Periaqueductal grey matter on the floor of the fourth ventricle
What is the reticular activating system responsible for
Alertness, sleep/wake, REM/non REM, respiratory centre, cardiovascular drive
What colour is bone on CT
White
What colour is bone on MRI
Black
How can you treat a non functioning eye
Prisms/squint surgery
How can you treat corneal injury
Eye drops and lubricant/ gold weight/ lateral tarsorrhaphy
How can you treat a non functioning smile
Cross facial nerve graft
How can you treat a non functioning swallow
NG tube/ Tracheostomy/ Percutaneous enterogastrostomy (PEG)
How can you treat a non functioning voice
Vocal cord injection
Disorders affecting the brainstem
Tumour, inflammatory, metabolic, trauma, spotaneous haemorrhage, infarction and infection
Criteria for brainstem death
Pupils, corneal reflex, caloric vestibular reflex, cough reflex, gag reflex, respirations and response to pain
