Neuro Flashcards
MS definition
Age of onset. Gender
Classification
Chronic autoimmune inflammatory demyelinating disorder of the CNS. Dissemination in time and space
Onset ~30yo. More females
Classification
- Relapsing-remitting (85%): Relapses, followed by remissions and periods of stability. In early stages, symptoms may go completely during remissions. After several relapses, residual damage to CNS results in only partial recovery during remissions
- Secondary progressive: Onset of MS is RR pattern but later neurological function gradually worsens, continued relapses. ~ 25% of RR progress to SP within 6y, and 50% within 15y of disease onset
- Primary progressive (10/15%): Steady progression and worsening from onset minus remissions
MS clinical presentation
Tingling
Eye (optic neuritis)
Ataxia + other cerebellar signs
Motor (usually spastic paraparesis)
Optic neuritis
- Initial presentation in 25%
- Partial/total unilateral visual loss over a few days. Often preceded by or with pain, particularly on movement
- Signs: reduced visual acuity of central vision. May be RAPD
Transverse myelitis
- Motor - weakness below level of inflammation, clumsiness, tonic spasms
- Sensory symptoms – Numbness, tingling , burning , Lhermitte’s phenomena (shock sensation radiation down the spine induced by neck flexion), altered temperature sensation
- Sphincter: Urinary urgency, frequency, hesitancy, retention, incontinence, constipation, faecal incontinence, erectile dysfunction
Cerebellar symptoms
- Symptoms and signs such as ataxia, vertigo, clumsiness, and dysmetria
Brainstem syndromes
- Ataxia
- Eye movement abnormalities that cause: diplopia, oscillopsia, nystagmus
- Bulbar muscle problems –> dysarthria or dysphagia
MS diagnosis
Management
Clinical: 2 or more attacks affecting different parts of the CNS: dissemination in time and space and exclusion of other possible causes.
DO bloods to exclude other diagnosis
- MRI: Multiple white matter plaques often perpendicular to lateral ventricles
- LP: IgG oligoclonal bands in CSF
- Visual evoked potential: Delayed auditory, visual and sensory
Management
- Symptomatic
- Fatigue: Modafinil
- Depression: SSRI
- Pain: Pregablin, Gabapentin
- Spasticity: Baclofen
- ED: Sildenafil
- Urgency/frew: Oxybutynin, tolterodine - Acute relapses
- Methylpred 1g/day IV or high dose oral for 3 days - Preventing relapses
- DMARDs: IFNb (in RR MS) or Glatiramer
- Biologics: Alemtuzumab (anti CD25), Natalizumab (anti VLA-4), Ocrelizumab (anti CD20 only one effective in PP MS)
Transverse myelitis definition
Causes
Management
Acute inflammatory disorder affecting the spinal cord with cord swelling and loss of function, characterised by development of motor weakness, sensory impairment, and autonomic dysfunction
Causes
•MS and neuromyelitis optica spectrum disorders: most common cause
•Para-infectious: Viral (e.g. HSV, CMV, EBV, HIV, rabies), Bacterial or fungal (e.g. Mycoplasma pneumonia, TB, syphilis, Lyme disease)
•Systemic autoimmune: SLE, Sjogren’s
•Systemic inflammatory: Sarcoidosis
•Paraneoplastic syndromes
Management Acute neurological deficits: •Methylprednisolone e.g. 1g/day IV for 3-5 days •If no response: Plasmapheresis •Supportive care and acute rehabilitation for all o DVT prophylaxis o Analgesia o Observe respiratory parameters
Define myasthenia gravis
Associations
Pathophysiology
Clinical presentation
Triggers
Chronic autoimmune disorder of the post-synaptic membrane at the NMJ in skeletal muscle
More common in young women
Associations
- Thymic disease
- RhA
- SLE
Pathophysiology
Circulating antibodies against the nicotinic AChR and associated proteins impair neuromuscular transmission –> weakness & fatiguability of the skeletal muscles
Clinical presentation
- Ptosis (bilateral)
- Diplopia
- Proximal limb weakness - increasing muscular fatigue with repetitive use throughout the day
- Weakness worsened by pregnancy, infection, emotion, exercise
- Sensory exam normal
Crisis = SOB severe enough to need mechanical ventilation
Triggers Beta blocker Penicillamine Procainamide Lithium Phenytoin Antibiotics e.g. gentamicin, macrolides, quinolones, tetracyclines
Myasthenia gravis investigations
Management
•Bloods
o Anti-AChR antibodies: +ve in 80%
o MuSK (muscle specific kinase) antibodies
•Serial pulmonary function tests aka SPIROMETRY: low FVC and NIF in MG crisis
•Tensilon test: give edrophonium (short-acting anti-cholinesterase) and see if it improves power
•EMG: Decrement in amplitude of compound muscle action potential following repetitive stimulation
•Thymus imaging: Image chest with CT or MRI for thymic hyperplasia/tumour (removal may improve the condition in some cases
Management •Oral Anticholinesterase: Pyridostigmine (cholinergic SE: salivation, lacrimation, sweats etc) •Immunosuppression: Prednisolone for relapses, azathioprine, methotrexate. Plasmapheresis or IVIg oStepped up (rather than normal weaning with steroids) as may be temporary exacerbation of symptoms before therapeutic effect •Thymectomy: If thymoma or no thymoma (If 18-65yo and pyridostigmine not working)
Myasthenic crisis: Intubation + mechanical ventilation + plasma exchange/IV Ig +/- Corticosteroid
Lamberton- Eaton myasthenia syndrome definition
Pathophysiology
Clinical presentation
Investigations
Management
Autoimmune disorder of the NMJ, often associated with small cell carcinoma of the lung
Pathophysiology
- Antibodies directed against VGCC: less influx of Ca2+ during presynaptic excitation –> less Ach release from presynaptic nerve terminals
Clinical presentation
Weakness but opposite of MG
o Leg weakness early (before eyes) i.e. gait difficulty
o Extra: Autonomic (dry mouth, constipation, impotence) and areflexia
o Movement improves symptoms of hyporeflexia and weakness
o Small response to edrophonium
Investigations
•EMG: Incremental increase of the compound muscle action potential after repetitive stimulation
• Anti-VGCC Abs +ve
• Chest CT scan: look for malignancy esp of lung
AChR antibodies and edrophonium testing negative
Management
•3,4 diaminopyridine (blocks K channels in nerve terminals –> increase in Ach release) or IVIg
• Regular CXRs, high resolution CTs as symptoms may precede Ca by 4yrs
Radial nerve palsy
Where does radial nerve originate from?
Where is it usually injured
What does it supply?
Symptoms
Signs
Investigations
Management
Origantes frim C5-T1
Supplies:
Triceps, Brachioradialis, Supinator, Wrist, Finger extensors, Long thumb abductor
Usually injured at shaft of humerus
Saturday night palsy
Symptoms
- Awake with wrist drop and finger drop
- Usually not aware of any sensory symptoms
Signs
- Wrist + finger drop
- Beware of false weakness of finger abduction because of finger position when wrist dropped
- May have subjectively altered light touch and pin over dorsum of hand at base of thumb and index and middle fingers
Investigations
- Nerve conduction studies
- Routine blood tests
- Consider hereditary tendency to pressure palsies (v rare)
Management
- Alcohol counselling, don’t drink until recovered
- Reassure that temporary - will recover fully in 4 weeks. Come back if only partially recovered in 4 weeks
- Splint to keep hand up
- Exercises e.g. play with ball
Nerve conduction studies + MRI if return in 4 weeks with no improvement
Median nerve palsy
Symptoms
Signs
Causes
Management
Carpal tunnel syndrome
Symptoms
- Aching pain in hand and arm worse at night
- Paraesthesia in thumb, index and middle fingers often relieved by shaking and massaging the hand
- Can be accompanied by pain in forearm
Signs
- May be none
- Wasting of thenar eminence, Weakness of APB
- May have altered sensation (light touch and pin) over index and middle finger and median half of ring finger
- Tinel’s sign
- Phalen’s sign
Causes
- Iidopathic = most common
- Water: Pregnancy, hypothyroid
- Radial fracture
- Inflammatory: RA
- Soft tissue swelling: Lipomas, acromegaly, amyloidosis
- Toxic: DM, EtOH
Management
Conservative - ergonomics e.g. wrist rests. taking breaks
Non-op - splints and corticosteroid injection. Move on to op if no improvement within 6 weeks
Op - Carpal tunnel decompression by division of flexor retinaculum. (Only one hand at a time and complications - scar and compression again)
Ulnar nerve palsy
Symptoms
Signs
Investigations
Management
Symptoms
- Numbness or tingling over ulnar border of hand and ring and little fingers
- Pt may notice tendency to drop objects
Signs
- Altered subjective sensation to light and pin over little finger and ulnar half of ring and ulnar border of hand
- Wasting of FDI (pudge sign)
- Wasting of ADB (hypothenar eminence)
- Froment’s sign (excess thumb flexion when pinching)
Investigations
- Nerve conduction studies
Management
- Surgical decompression or anterior transpostion can be performed
C spine assessment in trauma
Canadian C-spine rule: Clinically clears cervical spine fracture without imaging
- Any high risk factor which mandates radiography? Do it
- Age 65 or more
- Dangerous mechanism
- Paraesthesia in extremities - Any low risk factor which allows safe assessment of range of motion? If not, radiograph
- Simple rear end motor collision
- Sitting in ED
- Ambulatory at any time
- Delayed onset of neck pain
- Absence of midline c-spine tenderness
- -> if yes - Able to actively rotate neck? If able, no radiography
- 45 degrees left and right
Spinal cord tracts - which colour matter?
What are the 3 tracts,
Which direction do they go
What info to they carry
Where to they cross
White matter peripheral tracts
1) Lateral corticospinal
Enables intricate, strong organised movement
- originates in motor cortex neurones and terminates on motor nuclei of CN and anterior horn cells
- Crosses in medulla and pass to contralateral spinal cords, which then synapse with anterior horn cells
THIS IS KNOWN AS PYRAMIDAL SYSTEM - disease of which = UMN lesion
2) Dorsal
Light touch, Proprioception, Vibration, 2 point discrimination
- Ascend uncrossed to medulla. axons from 2nd order neurones cross midline and pass to thalamus
3) Spinothalamic
Pain and temperature
- Fibres synapse in dorsal horn of the cord, cross midline and ascend as the spinothalamic tracts to the thalamus
Spinal cord compression causes
Most common?
Presentation
Investigation
Most common = vertebral body neoplasms
- Mets from lung, breast, prostate, kidney or myeloma
- Myeloma
- Lymphoma
Disc and vertebral lesions - trauma, chronic degenerative
Inflammatory - epidural abscess, TB (Pott’s paraplegia)
Spinal cord neoplasms - primary (glioma, NF), Mets
Rarities - Paget’s disease, Bone cysts, epidural haemorrhage
Presentation
- Progressive weakness and UMN pattern and eventual paralysis in legs
- Arms affected if lesion above T spine
- Sensory level 1/2 spinal cord segments below level of compression
- May be loss of sphincter control and urinary incontinence
- May be painless urinary retention and constripation later
Investigation
- MRI
Management of spinal cord compression
Differentials
MRI - identify site and cause
Initial
- Surgical decompression of cord + stabilise spine
- Dexamethasone reduces oedema around lesion
- Think about VTE prevention
- Maintain volume and BP
- Support as needed - nutrition, ventilation, catheter
Further management depends on cause
Differentials
- Intrinsic lesion of the cord
- Transverse myelitis, anterior spinal artery occlusion and MS may present with rapid onset of paraparesis
- More insidious onset of weakness: MND (no sensory deficit), subacute combined degeneration of cord + non metastatic malignancy
Syringomyelia and syringobulbia - define
Where is lesion
Presentation
Management
Fluid filled cavity (syrinx) within spinal cord and brainstem respectively
Most lesions between C2 and T9
Presentation
- Spinothalamic (pain and temperature) loss i.e. loss of crossing fibres but preservation of dorsal columns - in a cape like distribution in upper limbs
- Unilateral/bilateral Horner syndrome
- Wasting + weakness in small muscles of hand due to damage of anterior horn cells at T1 level (common site for syrinx)
- Spastic paraparesis develops only after cavity markedly distended and compresses on corticospinal tracts
Management
MRI
Surgical decompression of foramen magnum sometimes slows down deterioration
What is freidrich’s ataxia
AR hereditary condition in fraxtin gene on Chr 9
Fraxtin found in spinal cord, heart and pancreas
Presentation
- Progressive degeneration of the posterior columns, corticospinal tract and dorsal and ventral spinocerebellar tract (proprioception)
- Ataxia - spreading from distal legs
- Dysarthria
- Nystagmus
- Dysdiadochokinesis
- Sensory neuropathy: Absent ankle jerk, absent joint position and vibration sense
- Pyramidal signs: Upgoing plantar (despite absent ankle jerk), weakness
Other features
– Optic atrophy
– Pes cavus and scoliosis
– Cardiomyopathy + associated arrhythmias
– Diabetes
Management
- No cure
- Treat CCF, arrhythmia and DM
Absent ankle jerk + Extensor planter response causes
1) Combined pathology e.g. cervical spondylosis + peripheral neuropathy
2) MND
3) Subacute combined degeneration of the cord (Fit B12 myelopathy)
4) Freidreich ataxia
5) Tabes dorsalis/tertiary neurosyphillis
Types of MND
Worst and best prognosis
Diagnosis
Management
1) Progressive muscular atrophy - mainly LMN (best prog)
2) Amytrophic lateral sclerosis - classic UMN + LMN
3) Progressive bulbar and pseudo bulbar palsy (worst prog)
4) Primary lateral sclerosis - solely UMN
NO SENSORY SIGNS OR MOTOR INVOLVEMENT OF EYE OR SPHINCTERS
Diagnosis = clinical
- Supported by EMG: Denervation
- Nerve conduction studies: Reduction in motor nerve conduction amplitude
Management - no cure, need counselling
Drugs: RILUZOLE = gultamate receptor antagonist - only 2/3 months extra survival
Supportive care
- ST + communication aids
- PT, splints, walking aids + wheelchairs
- Spasticity: Baclofen or gabapentin
- Dysphagia: Blend food
- Excess saliva: Position, oral care, suctioning. Try anti-muscarinic
- Involve palliative care
Prognosis
<3yrs post onset in most
What is amyotrophic lateral sclerosis
MND type
Combo of disease of lateral corticospinal tracts and anterior horn cells
Presentation
- Spastic tetra paresis or paraparesis with added LMN (wasting + fasciculation’s) i.e. UMN + LMN
(LMN = muscle cramps, fasiculations inc tongue, wasting and weakness)
- Onset tends to be focal, distal, asymmetrical and progress from one limb to another
NB often a mixed bulbar and pseudo bulbar picture
What is progressive bulbar and pseudo bulbar palsy
Type of MND - destruction of upper (pseudo bulbar) and Lowe (bulbar) motor neurone in the lower CNs (IX-XII)
Pseudobulbar = UMN lesion of muscles of swallowing and talking
- Dysarthria, dysphagia
- Tongue small and spastic, no dasiculations
- Exaggerated jaw jerk
- Emotionally labile
Causes: Cerebrovascular disease, MND, MS
Bulbar = LMN of tongue and muscles of swallow/talk - Dysphagia, dysarthria - Flaccid fasciculation tongue - Jaw jerk absent/normal - Speech quiet, hoarse or nasal Causes: MND, GBS, Syringobulbia, MG
Sciatic nerve - roots
Supply to what
What does it divide into
Sacral plexus (L4-S3) Supplies hip extensors and knee flexors
2 parts to the sciatic nerve
1) Common peroneal (posterior) further divides:
- Superficial: Ankle eversion
- Deep: Toe and dorsiflexion
2) Tibial nerve (anterior)
- ankle inversion and plantar flexion
RAdiculopathy definition
Causes
Presentation
Spinal nerve root lesion
Causes
- Cervical and lumbar spondylosis (degenerative changes inc. disc prolapse and osteophytes)
- Trauma
- Tumours (NF, neuroma, lymphoma, mets)
- HZV (Shingles)
- Meningeal infiltration + inflammation
- Arachnoiditis
Presentation
1) Pain: Severe, sharp, shooting, burins into dermatome or myotome supplied by root.
- Aggravated by movement, strain or cough
- May arise from soft tissue and joints also
2) Neuro signs
- LMN signs: Wasting, fasciculations, flaccid weakness and reduced/absent reflexes in affected myotome
- Sensory impairment in affected dermatome
C7 nerve
Myotome
Reflex
Dermatome
Myotome: Wrist flexion, elbow extension
Reflex = Triceps
Dermatome = Middle finger
NB need to add other nerve roots
causes of cauda equina
Differentials
Disc prolapse - most common at L5/S1 and L4/L5
Trauma e.g. vertebral fractures and subluxation
Neoplasm - primary or mets from lung, breast, kidney, prostate, thyroid
Infection e.g. discitis of Potts disease
Chronic spinal inflammation e.g. AS
Iatrogenic e.g. haematoma secondary to spinal anaesthesia
Differentials
- Radiculopathy: radiating back pain but no faecal, urinary or sexual dysfunction
- cord compression - surgical emergency but UMN signs
cauda equina symptoms and signs
tests to do
Management
Severe bilateral back pain Reduced LL sensation Bladder/bowel dysfunction (esp urinary retention) LL motor weakness Impotence
o/e
- Perianal anaesthesia aka saddle
- Loss of anal tone (PR)
- LL weakness and loss of reflexes
- Urinary retention’s
Tests
- PR
- Post void bladder scan
- whole spine MRI
Management
- Early neurosurgical review for urgent decompression
- High dose steroids e.g. dexamethasone to reduce any localized swelling
- In cases caused by malignancy, radio/chemotherapeutic can be used
Migraine requirements to diagnose
A At least 5 attacks fulfilling criteria B-D
B Headache attacks lasting 4-72 hours* (untreated or unsuccessfully treated)
C Headache has at least two of the following characteristics:
1. unilateral location*
2. pulsating quality (i.e., varying with the heartbeat)
3. moderate or severe pain intensity
4. aggravation by or causing avoidance of routine physical activity (e.g., walking or climbing stairs)
D During headache at least one of the following:
1. nausea and/or vomiting*
2. photophobia and phonophobia
E Not attributed to another disorder (history and examination do not suggest a secondary headache disorder or, if they do, it is ruled out by appropriate investigations or headache attacks do not occur for the first time in close temporal relation to the other disorder)
NICE criteria the following points are noted:
NICE suggests migraines may be unilateral or bilateral
NICE also give more detail about typical auras:
Auras may occur with or without headache and:
are fully reversible
develop over at least 5 minutes
last 5-60 minutes
Status epilepticus management
Immediate: ABC, High flow Oxygen, BM, temperature
5 mins - No IV access - Buccal midazolam 0.5mg/kg - Iv access - IV lorazepam 0.1mg/kg Gain IV access if not already. Send blood samples
15 mins - IV lorzepam 0.1mg/kg This step should be in hospital Call for senior help Start to prepare phenytoin for 4th step Re-confirm it is an epileptic seizure
25 mins
- Phenytoin 20 mg/kg by intravenous infusion over 20 mins
or (if on regular phenytoin)
- Phenobarbital 20 mg/kg intravenously over 5 mins
45 mins
Rapid sequence induction of anaesthesia using thiopental sodium 4 mg/kg intravenously
Trigeminal neuralgia
Symptoms
Red flags
Management
Trigeminal neuralgia is a pain syndrome characterised by severe unilateral pain.
Causes
The vast majority of cases are idiopathic but compression of the trigeminal roots by tumours or vascular problems may occur
Red flags
- Sensory changes
- Deafness or other ear problems
- History of skin or oral lesions that could spread perineurally
- Pain only in the ophthalmic division of the trigeminal nerve (eye socket, forehead, and nose), or bilaterally
- Optic neuritis
- A family history of multiple sclerosis
- Age of onset before 40 years
Management
- Carbamazepine is first-line
- failure to respond to treatment or atypical features (e.g. < 50 years old) should prompt referral to neurology
What is restless leg syndrome
Causes
Diagnosis
Management
Syndrome of spontaneous, continuous lower limb movements that may be associated with paraesthesia.
Symptoms/signs
Uncontrollable urge to move legs (akathisia).
Symptoms initially occur at night but as condition progresses may occur during the day. Symptoms are worse at rest
Paraesthesias e.g. ‘crawling’ or ‘throbbing’ sensations
movements during sleep may be noted by the partner - periodic limb movements of sleeps (PLMS)
Causes/associations
- FH
- iron deficiency anaemia
- uraemia
- diabetes mellitus
- pregnancy
Diagnosis = clinical but do FBC to exlude Fe deficiency anaemia
Management
- Simple measures: walking, stretching, massaging affected limbs
- Treat any iron deficiency
dopamine agonists are first-line treatment (e.g. Pramipexole, ropinirole)
- Benzodiazepines
- Gabapentin
Alternative to clopidogrel post TIA
Dual antiplatelet with aspirin + modified release dipyramidole
Proplem with clopidogrel is usually GI e.g. diarrhoea
Features of a Posterior inferior cerebellar artery stroke
AkA
Ipsilateral: facial pain and temperature loss, Horner syndrome, Ataxia, nystagmus
Contralateral: limb/torso pain and temperature loss
Lateral medullary syndrome
Wallenberg syndrome
Most commonly survived stroke that affects the brainstem
Mechanisms of damage to peripheral nerves
What do the nerve conduction studies show for main 2
1) Demyelination (Schwann Cell damage –> slowing of conduction) caused by pressure e.g. entrapment or by inflammation e.g. GBS
Nerve conduction: Decreased conduction velocity
2) Axonal degeneration: Conduction velocity initially normal. Typical in toxic neuropathies
Nerve conduction: Decreased amplitude of impulse
- Compression: Focal demyelination at point of compression –> disruption of conduction e.g. Carpal Tunnel Syndrome
- Infarction: Micro-infarction of vasa nevorum occurs in diabetes and arteritis. Wallerian degeneration occurs distal to infarct
- Infiltration: By inflammatory cells in leprosy, granulomas (e.g. sarcoid) and by neoplastic cells
Investigations for a peripheral nerve disorder
Blood: FBC, ESR, CRP, U&Es (renal function), LFTs, Glucose, Autoantibodies, Vit B12, Serum protein electrophoresis
Nerve conduction studies;
Axonal degeneration = reduced amplitude
Demyelination = reduced conduction velocity
Also characterise whether sensory and/or motor fibres involved and localise site of abnormality
EMG
Fine need inserted into muscle to discern whether partial or complete innervation present and if re–innervation occuring
Nerve biopsy
Sural nerve most commonly as purely sensory and so resulting deficit is trivial
Can confirm vasculitis or other inflammatory process
CSF
May be helpful in GBS or CIDP, when protein raised, without inflammatory cells
Mononeuritis multiplex define
Causes
Investigations
2 or more peripheral nerves affacted
Causes : WAARDS PLC W = Wegener's A = Aids A = Amyloid R = RA D = DM = most common S = Sarcoidosis P = PAN L= Leprosy C = Carcinomatosis
Investigations - as for peripheral nerve disorders + EMG helps define site of lesion:
Blood: FBC, ESR, CRP, U&Es (renal function), LFTs, Glucose, Autoantibodies, Vit B12, Serum protein electrophoresis
Nerve conduction studies;
Axonal degeneration = reduced amplitude
Demyelination = reduced conduction velocity
Also characterise whether sensory and/or motor fibres involved and localise site of abnormality
EMG
Fine need inserted into muscle to discern whether partial or complete innervation present and if re–innervation occuring
Nerve biopsy
Sural nerve most commonly as purely sensory and so resulting deficit is trivial
Can confirm vasculitis or other inflammatory process
CSF
May be helpful in GBS or CIDP, when protein raised, without inflammatory cells
Ulnar nerve motor and sensory innervation
Ulnar nerve palsy causes
Motor
1) Flexor carpi ulnaris
2) Flexor digitorum profundus
Then all small muscles of hand except APB. OPB, Lateral 2 lumbricals and part of FPB
Sensory
Ulnar 1 and 1/2 fingers
Causes of ulnar nerve palsy
Entrapment usually at elbow here nerve compressed within cubital tunnel, which lies behind medial epicondyle
- Can follow ulnar fracture
- Micro injury by leaning on elbow
- Vibrating tools and cyclists
- Stretching of ulnar nerve e.g. sleeping with elbow bent to more than 90degrees
