Neuro Flashcards
Brain tumours
Can be primary / secondary (10x more common)
Brain tumours patho
Primary Majority are gliomas astrocytoma (85-90%) oligodendroglioma (5%) Also ependymomas, meningiomas, neurofibromas (Schwannomas), craniopharyngiomas
Secondary Non-small cell lung (most common) Small cell lung breast melanoma renal cell GI
Tumours act as space-occupying lesion, increase ICP. Initially, no symptoms, then sharp rise in ICP, symptoms, risk of coning, midline shift
Brain tumours Px
3 cardinal symptoms:
Symptoms of raised ICP
headache (increased by coughing, straining), drowsiness, vomiting, papilloedema (optic disc swelling), retinal oedema, haemorrhages
Progressive neurological deficit
Focal - motor (ataxia), sensory, speech, visual, deafness, memory, personality change
Depends on part of brain affected:
Temporal - dysphasia, amnesia
Frontal - hemiparesis, personality change, Broca’s dysphasia
Parietal - hemisensory loss, reduction in 2-point discrimination, dysphasia, astereognosis (cannot recognise object from touch alone)
Occipital - contralateral visual defects
Cerebellum - DANISH - dysdiadochokinesis (impaired rapidly alternating movt), ataxia/gait, nystagmus, intention tremor, slurred speech, hypotonia
Epilepsy
focal seizures more common with tumours
Brain tumour DDx
other causes of space-occupying lesion - abscess, haematoma, aneurysm, cyst
stroke
Brain tumour Ix
CT/MRI
Bloods - FBC, U+W, LFTs, B12 etc
Biopsy - via skull burr hole
LP CONTRAINDICATED - withdrawing CSF may provoke immediate coning
Brain tumour Mx
Surgery to remove mass Chemotherapy, radiotherapy Oral dexamethasone Anticonvulsants - oral carbamazepine Palliative care
Brain tumour Cx
acute haemorrhage into tumour, blockage of CSF outflow - hydrocephalus, coning, Cx of radiotherapy
Cauda equina syndrome
compression of cauda equina (~L1), caused by:
disc prolapse, tumour, infection, bleeding, trauma
Cauda equina syndrome Px
signs
loss of anal tone on PR
loss of anal wink reflex
loss of sensation around saddle region
symptoms urinary retention, overflow incontinence bilateral leg pain impotence loss of power in legs, gait disturbance numbness, paraesthesia
Cauda equina syndrome DDx
difference with this and lesions higher up in cord - leg weakness is flaccid and areflexic, not spastic and hyperreflexic
conus medullaris syndrome, mechanical back pain, fracture, tumour, spinal cord compression
Cauda equina syndrome Ix
PR examination
lumbar spine MRI
Cauda equina syndrome Mx
emergency lumbar decompression
Dementia
syndrome caused by a number of brain disorders, which cause memory loss, decline in cognition, difficulties with ADL
Dementia causes
Alzheimer’s - degeneration of cerebral cortex, cortical atrophy, neurofibrillary tangles, amyloid plaque formation, reduced ACh production
Vascular - brain damage from cerebrovascular disease - stroke, multi-infarct
Dementia with Lewy bodies - deposition of abnormal proteins, has features of Parkinsonism
Frontotemporal dementia - specific degeneration of frontal and temporal lobes of the brain
Mixed dementia
Parkinson’s disease
Potentially treatable - substance misuse, hypothyroidism
Dementia Px
Cognitive impairment - difficulties with memory, language, attention, thinking
Psychiatric/behavioural disturbances - changes in personality, emotional control, social behaviour
Difficulties with ADL - driving, shopping, eating, dressing
Dementia Ix
Clinical dx Screen for cognitive impairment - MMSE Medication review to exclude drug cause Identify depression, look for reversible/organic causes MRI, functional imaging (eg PET) EEG - in suspected delirium, FTP
Dementia Mx
AChE inhibitor - rivastigmine
Anti-glutaminergic tx - memantine (NMDA antagonist)
Challenging behaviour - trazadone/lorazepam
SSRI for depression - citalopram
Non-pharmacological - eg aromatherapy, animal assisted therapy, massage, music
Palliative care
Depression
low mood +/- loss of interest and pleasure in most activities
Depression patho
associated diseases
dysthymia (chronic depressive state 2+yrs), eating disorders, substance misuse, other psychiatric conditions, various medical conditions
causes
anxiety, alcohol abuse, substance misuse, Parkinson’s, MS, endocrine, medication
RFs
female, past history of depression, significant physical illness, other mental health problems, psychosocial issues
Depression Px
Persistent sadness/low mood Loss of interest in most activities fatigue, loss of energy worthless, excessive/inappropriate guilt recurrent thoughts of death, suicidal thoughts, suicide attempts diminished ability to think insomnia changes in appetite, wt loss
Depression DDx
bipolar disorder, schizophrenia, dementia, seasonal affective disorder, bereavement, organic cause (eg hypothyroidism), drugs
Depression Ix
Assessment - PHQ-9, HAD scale, Beck’s Depression Inventory
Assess suicide risk
Past psychiatric history
Depression Mx
Mental health team - crisis team, IAPT
CBT, counselling
SSRIs - fluoxetine, sertraline, citalopram
TCAs - amitriptyline, amoxapine
Electroconvulsive therapy (ECT)
Depression Cx
Impaired QoL, social difficulties, suicide
Encephalitis
infection and inflammation of the brain parenchyma
Encephalitis causes
Viral - HSV 1, 2, VSV, CMV, HIV, mumps, measles
Bacterial meningitis, TB, malaria
RFs - extremes of age, immunocompromised, history of travel / animal bite
Encephalitis Px
fever + headache + altered mental status
Fever, headaches, myalgia, fatigue, nausea
Personality and behavioural changes, decreased consciousness, confusion, drowsiness
Hemiparesis, dysphasia, seizures, raised ICP, coning, coma
May have signs of meningitis
Encephalitis DDx
meningitis, stroke, brain tumour
Encephalitis Ix
MRI Contrast-enhanced CT EEG LP - CSF elevated lymphocytes, viral detection by PCR Blood and CSF serology
Encephalitis Mx
Antiviral - acyclovir
Antiseizure - primidone, phenytoin
If meningitis suspected - benzylpenicillin
Epilepsy
recurrent tendency to spontaneous intermittent abnormal electrical activity, manifesting in seizures
Epileptic seizure
paroxysmal event caused by excessive hypersynchronous neuronal discharges
Convulsions
motor signs of electrical discharges
Elements of a seizure
Prodrome - change in mood/behaviour before seizure, might not occur
Aura - deja vu, strange gut feeling, strange smells, flashing lights, part of seizure where patient is aware, implies focal seizure, but not necessarily, from temporal lobe
Post-ictal - after, headache, confusion, myalgia, sore tongue, dysphasia if seizure in temporal lobe
Types of seizures
Focal (partial) seizures - small area, one hemisphere
- SIMPLE - without consciousness impairment, focal motor, sensory, autonomic or psychic symptoms, no post-ictal
- COMPLEX - with conscious impairment, most commonly from temporal lobe, post-ictal confusion
- SECONDARY GENERALISED - bilateral, convulsive seizure, starts locally, spreads widely
Generalised seizures - widespread electrical discharge in both hemispheres
- ABSENCE SEIZURES - brief pauses (eg stops mid sentence), presents in childhood
- TONIC-CLONIC - loss of consciousness, limbs stiffen (tonic), jerk (clonic), post-ictal confusion, drowsiness
- MYOCLONIC - sudden jerk of limb, face, trunk
- ATONIC (AKINETIC) - sudden loss of muscle tone, fall, no LOC
- INFANTILE SPASMS - seizure in baby
Epilepsy causes
idiopathic cerebrovascular disease trauma cranial surgery neurodegenerative diseases brain neoplasm genetic diseases drugs metabolic medical disorders - electrolytes
Epilepsy RFs
FHx, premature babies small for age, childhood febrile convulsions, abnormal blood vessels in brain, Alzheimers/dementia, drugs, alcohol withdrawal, stroke, trauma
Epilepsy Px
PRIMARY GENERALISED Generalised tonic-clonic (grand-mal) no aura LOC tonic - stiff clonic - jerk eyes open, tongue bitten incontinent post-ictal - drowsy, confusion, coma
Absence (petit mal)
childhood
stops activity, stares, turns pale, carries on as normal
Myoclonic
sudden isolated jerk of limb, face, trunk
Tonic seizure
sudden sustained increased tone, stiffness, no jerking, characteristic cry/grunt
Atonic (akinetic)
sudden loss of muscle tone, cessation of movt, fall
PARTIAL/FOCAL
Simple partial
No LOC or memory, focal motor, sensory, autonomic or psychic symptoms, no post-ictal symptoms
Complex partial
LOC, memory, commonly temporal (understanding speech, memory, emotion), post-ictal confusion
Secondary generalisation
Starts focally, becomes widespread, typically convulsive
Epilepsy Px different lobes
Temporal lobe (memory, emotion, speech understanding) aura - deja vu, funny smells anxiety, out-of-body experience, automatisms (lip smacking, chewing, fiddling)
Frontal lobe (motor and thought processing) motor features, Jacksonian march (seizure 'marches' up/down motor homonculus starting in face/thumb) Post-ictal Todd's paralysis - paralysis of limbs
Parietal lobe (interprets sensations) sensory disturbances - tingling, numbness
Occipital lobe (vision) visual phenomena - spots, lines, flashes
Epilepsy DDx
postural syncope, cardiac arrhythmia, TIA, migraine, hyperventilation, hypoglycaemia, panic attacks, non-epileptic seizure
Epilepsy Ix
For clinical Dx: >2 unprovoked seizures >24hrs apart
EEG
MRI
CT head
Bloods - rule out metabolic causes, find comorbidities
Genetic testing - juvenile myoclonic epilepsy
Rule out provoking causes - trauma, stroke, haemorrhage, increased ICP, alcohol/benzo withdrawal, infection, drugs
Epilepsy Mx
Emergency
ABCDE
Check glucose
Prolonged/repeated - benzos: diazepam/lorazepam
IV phenytoin loading (anti-seizure)
If still fitting - anaesthetic and ventilation
Medication - all AEDs (anti-epileptic drugs)
Primary generalised Tonic clonic (grand mal) - sodium valproate, lamotrigine, carbamazepine
Absence (petit mal) - sodium valproate, ethosuximide, lamotrigine
Partial/focal
carbamazepine, sodium valproate, lamotrigine
Neurosurgical tx - resection, vagal nerve stimulation
Epilepsy Cx
Status epilepticus - continuous seizures
Sudden unexpected death epilepsy (SUDEP)
Extradural/epidural haemorrhage
Collection of blood between dura mater and bone
EDH patho
traumatic head injury, fracture of temporal/parietal bone, laceration of middle meningeal artery
also due to any tear in dural venous sinus
EDH Px
Head injury
Brief LOC / drowsiness
Lucid interval - time between injury and decrease in consciousness, while haematoma is small
Severe headache, N+V, confusion, seizures - rising ICP
Hemiparesis, brisk reflexes
Ipsilateral pupil dilates, coma deepens, bilateral limb weakness, deep/irregular breathing - brainstem compression
Decreased GCS, coning
Bradycardia and BP increase - late signs
EDH DDx
Epilepsy, carotid dissection, CO poisoning, SDH, SAH, meningitis, intoxication
EDH Ix
Head CT - hyperdense haematoma, biconcave / lens shaped adjacent to skull (blood forms more rounded shape compared to sickle-shaped SDH as the tough dural attachments to skull keep it localised)
Skull xray - may be normal, fracture lines
EDH Mx
ABCDE
IV mannitol - if increased ICP
Neurosurgery - clot evacuation +/- ligation of bleeding vessel
Subdural haemorrhage
blood between dura and arachnoid layers
can be acute, subacute, chronic
Simple / complicated (underlying parenchymal injury)
SDH patho
Commonly following rupture of bridging vein between cortex and venous sinus
Bleed from damaged cortical artery (branches of ACA, MCA, PCA)
Clotting disorders
At risk - infants, elderly, alcoholism, on anticoagulants
Cerebral atrophy in elderly and alcoholism - tension on veins
Trauma, bleeding from bridging veins between cortex and venous sinuses, bleed forms haematoma, reduces pressure and bleeding stops, later when haematoma breaks down, insoluble proteins -> soluble, increase in osmotic pressure, water sucked into haematoma, enlarges, ICP rises
SDH Px
Days/weeks/months between injury and symptoms
Lucid interval
signs
increased ICP
seizures
localising neurological symptoms (unequal pupils, hemiparesis) - occur late
Stupor (decreased consciousness), coma, coning
symptoms
fluctuating level of consciousness
slowing, sleepiness, headache, personality change, unsteadiness
SDH DDx
stroke, dementia, CNS masses, EDH, SAH
SDH Ix
Head CT - sickle-shaped collection of blood, one hemisphere, hyperdense crescent-shaped
MRI for subacute, smaller
Bloods - FBC, U+E, LFT, thrombocytopenia, coagulation screen
SDH Mx
ABCDE
Reverse clotting abnormalities
Neurosurgery - irrigation/evacuation via burr hole craniotomy
IV mannitol
Address cause of trauma, eg falls, abuse
SDH Cx
coning, raised ICP, seizures, coma
Subarachnoid haemorrhage
bleed between subarachnoid and pia
SAH causes
Berry aneurysm rupture (80%), results in tissue ischaemia, raised ICP, pressure on brain (bleed acts as space-occupying lesion)
Arteriovenous malformations (15%)- vascular development malformation
Others - encephalitis, vasculitis, tumour, idiopathic
SAH RFs
HTN, known aneurysm, FHx, diseases that predispose to aneurysm (PKD, Ehlers Danlos syndrome, coarctation of aorta), smoking, bleeding disorders, post-menopausal decreased oestrogen
SAH Px
signs
neck stiffness
Kernig’s - unable to extend patient’s legs at knee when thigh is flexed
Brudzinski’s - when patient neck flexed by doctor, patient will flex hips and knees
retinal, subhyaloid, vitreous bleeds
Papilloedema
Focal neurology - eg pupil changes, CN3 palsy
Later deficits
BP increase as reflex to haemorrhage
symptoms thunderclap headache vomiting collapse seizures coma/drowsiness
SAH DDx
meningitis, migraine, intracerebral bleed, cortical vein thrombosis, other causes of stroke
SAH Ix
Head CT - star-shaped lesions due to blood filling gyri patterns
CT angiography - see aneurysm
LP - bloody CSF, then becomes xanthochromic (yellow) due to bilirubin from Hb breakdown
ECG - QT prolongation, Q waves, dysrhythmias, ST elevation
SAH Mx
IV fluids
Nimodipine - CCB, reduces vasospasm
Surgery - endovascular coiling / surgical clipping, stents
SAH Cx
Rebleeding, cerebral ischaemia, hydrocephalus (tx ventricular/lumbar drain), hyponatraemia
Guillain-Barre syndrome
autoimmune condition - acute inflammatory demyelinating ascending polyneuropathy (symmetrical) affecting PNS / Schwann cells
GBS patho
usually triggered by infection (eg campylobacter, CMV, VZV, HIV, EBV) - resp/GI infection
auto-AB mediated nerve cell damage - damage to Schwann cells, demyelination, reduction in peripheral nerve conduction
GBS Px
Symmetrical ascending muscle weakness, paralysis
Proximal muscles more affected, then trunk, resp muscles, cranial nerves later
Pain
Sensory signs may be absent
Paraesthesia
Reflexes lost
Hypotonia
Autonomic features - sweating, raised pulse, BP changes, arrhythmias
Progressive for 4wks then recovery
GBS DDx
Other causes of acute paralysis
Brain - stroke, encephalitis Spinal cord - compression, poliomyelitis Peripheral nerve - vasculitis, lead poisoning NMJ - MG, botulism Muscle - hypokalaemia, polymyositis
GBS Ix
Usually clinical Dx
Nerve conduction studies (NCS) - slowing of conduction
LP - CSF raised protein, normal WCC
Spirometry - monitor FVC, if deceases, go to ITU
Maybe AB screen electrolytes, ECG abnormalities
GBS Mx
ITU and ventilate if FVC <80%
IVIg (IV immunoglobulin)
Plasma exchange
Pain relief for neuropathic pain
Headaches
Primary Tension - most common, pain like hand squeezing head Cluster - pain around one eye Sinus - pain behind forehead/cheekbones Migraine - pain, nausea, visual changes
Secondary
Could be GCA, trigeminal neuralgia, medication overuse
Red flags for headache HIV, immunosuppressed Fever Thunderclap headache Seizure Suspected meningitis, encephalitis Red eye? acute glaucoma Headache + new focal neurology, eg papilloedema
Migraine
Recurrent throbbing headache often preceded by aura, associated with N+V, visual changes
May be caused by changes in brainstem and its interactions with trigeminal nerve, or brain chemical imbalance
Migraine triggers - CHOCOLATE
Chocolate Hangovers Orgasms Cheese Oral contraceptives Lie ins Alcohol Tumult - loud noise Exercise
Migraine Px
Prodrome - yawning, cravings, mood/sleep changes
May have aura
Unilateral, pulsing, pain in head Aggravated by routine physical activity N+V, photophobia, phonophobia (sound sensitive) Visual disturbances Paraesthesia
POUND Pulsating Onset over 4-72hrs Unilateral Neurological signs, eg photophobia Disabling – patient often wants to be in a dark room
Migraine Ix
Clinical dx
Examine - eyes, BP, head and neck
Exclude other causes - CRP, ESR, red flags, maybe LP if indicated
Migraine Mx
Reduce triggers - dietary factors
NSAIDs, ibuprofen, naproxen
Aspirin, paracetamol
+/- antiemetic - prochlorperazine
Triptans - sumatriptan
Prevention
BB (propranolol), TCA (amitriptyline), anti-convulsant (topiramate)
Tension headache
most common primary headache, no organic cause
Tension headache RFs
stress, sleep deprivation, bad posture, hunger, eye strain, anxiety, noise
Tension headache Px
Bilateral, pressing/tight, non-pulsatile, like a tight band
Pressure behind eyes
no vomiting, no sensitivity to head movt, no aura
Tension headache Ix
Clinical dx
Tension headache Mx
Reassure, exercise, avoid triggers
Stress relief - massage, acupuncture
Aspirin, paracetamol, ibuprofen
Cluster headache
most disabling primary headache, in/around eye
Cluster headache Px
Abrupt onset Excruciating pain around one eye, temple/forehead Unilateral Eye may be watery, bloodshot, facial flushing, rhinorrhoea (blocked nose), miosis (excessive pupil constriction) +/- ptosis Pain rises to crescendo Often nocturnal \+/- vomiting episodic
Cluster headache Ix
Clinical Dx
Cluster headache Mx
O2
Triptan - sumatriptan
Prevention - CCB (verapamil), prednisolone may help
Chickenpox
caused by varicella-zoster virus
Chickenpox patho
transmitted by resp droplets
invades resp mucosa, replicates in lymph nodes, infects skin epithelial cells
Cx can occur in - immunocompromised, older, steroid use, malignancy, pregnancy (danger to neonates, mother can get pneumonia)
Chickenpox Px
Prodrome (1-2 days) - fever, malaise, headaches, abdo pain
Rash - pruritic, erythematous macules -> vesicles, crust in 48hrs
Chickenpox DDx
generalised herpes zoster or simplex, dermatitis herpetiformis, impetigo, contact dermatitis
Chickenpox Ix
Clinical dx
PCR
Investigate Cx - CXR, LP
Chickenpox Mx
Fluids, avoid scratching
Paracetamol
Self-limiting
Acyclovir if at risk of Cx
Chickenpox Cx
secondary infections of lesions
viral pneumonia
encephalitis
other CNS complications, other infections
Shingles
Herpes zoster - reactivation of VZV
Shingles patho
VZV remains latent in sensory ganglia, reactivated, in dorsal root, travels down affected root in dermatomal distribution
RFs - elderly, immunocompromised
Shingles Px
Pre-eruptive phase
burning, itching, paraesthesia in one dermatome
malaise, myalgia, headache, fever, maybe lymphadenopathy
eruptive phase rash - papules, vesicles in one dermatome neuritic pain paraesthesia does not cross midline
chronic phase
Post-herpetic neuralgia (PHN) - persistent pain >30d after acute infection
Shingles Ix
Clinical dx
Shingles Mx
Antivirals - acyclovir
Topical AB for tx of secondary bacterial infection
Analgesia, ibuprofen
PHN Tx - TCA (amitriptyline), anti-epileptic (gabapentin), anticonvulsant (carbamazepine)
Vaccine at 70yo to prevent reactivation
Shingles Cx
Ophthalmic - can affect sight
PHN
Huntington’s disease
neurodegenerative disorder characterised by lack of the inhibitory NT GABA
causes chorea - jerky, semi-purposeful movts, may interfere with voluntary movts
HD patho
autosomal dominant, repeated expression of CAG on chromosome 4, mutation in huntingtin gene
cerebral atrophy, loss of neurons in caudate nucleus, putamen, decreased ACh and GABA synthesis, decreased inhibition of dopamine release, excessive thalamic stimulation, excessive movts
Corpus striatum loss
HD Px
Prodromal - mild psychotic and behavioural symptoms
Chorea - relentlessly progressive, jerky, explosive, rigid involuntary movts, stop when sleeping
Dysarthria, dysphagia, abnormal eye movts
Aggression, addictive behaviour, apathy, self-neglect, depression/anxiety
Dementia
Seizures
HD DDx
other causes of chorea - SLE, stroke of basal ganglia
HD Ix
Clinical Dx
Genetic testing - many CAG repeats
CT/MRI - caudate nucleus atrophy, increased frontal horn size of lateral ventricles
HD Mx
Counselling, genetic counselling
Symptomatic Mx of chorea
Benzodiazepines - attach to GABA receptors
Sulpiride - neuroleptic, depresses nerve function
Tetrabenazine - dopamine depleting agent
SSRI for depression
Antipsychotic - haloperidol (neuroleptic)
Risperidone to tx aggression
Meningitis
inflammation of the meninges
Meningitis patho
Bacterial
group B strep, listeria, E coli, H.influenzae, N.meningitidis, S.pneumoniae, TB, G- (Klebsiella, pseudomonas, enterobacter), staph…
N.meningitidis - transmitted by droplet spread, can lead to meningococcal septicaemia (bacteria invades blood, petechial rash, sepsis)
Aseptic meningitis - CSF has cells, but no bacterial cultures
Viral (most common), fungal, parasites
Non-infective meningitis
malignant cells, chemical, medication, sarcoidosis, SLE
Meningitis Px
Fever, headache, neck stiffness
Leg pains, cold hand+feet, abnormal skin colour
Photophobia
Reduced GCS, coma
Seizures, focal CNS signs, petechial rash (stays red when glass pressed)
Shock, papilloedema, vomiting
Kernig’s - pain + resistance on passive knee extension with hip fully flexed
Brudzinski’s - passive flexion of neck causes patient to raise knees/hips
Opisthotonos - spasm of muscles causing backwards arching of head, neck, spine
Meningitis DDx
malaria, encephalitis (altered mental state is predominant symptom), septicaemia, dengue, tetanus, SAH
Meningitis Ix
Blood culture (before LP and any tx)
Bloods - FBC, U+E, CRP, glucose
LP - to MC&S
- Bacteria - polymorphs, raised protein, low glucose, turbid/yellow colour
- TB - lymphocytes, raised protein, low/normal gluc
- Virus - lymphocytes, normal/high protein, normal gluc
CT head
Throat swabs
Serum PCR for virus
Meningitis Mx
ABs - IV ceftriaxone/cefotaxime, add amoxicillin if >60yo or immunocompromised
Chloramphenicol if allergic to beta lactams
Dexamethasone for meningism, seizures, ICP
Maybe IV vancomycin for return travellers
Prophylaxis for contacts - oral ciprofloxacin/oral rifampicin
AB for specific org
Meningitis Cx
Meningococcal septicaemia - IV benzylpenicillin / IV cefotaxime
Septic shock, DIC, coma, cerebral oedema, raised ICP
Motor neuron disease
cluster of neurodegenerative diseases - destruction of motor neurons
loss of neurons in motor cortex, cranial nerve nuclei, anterior horn cells
MND patho
Usually sporadic, possibly oxidative stress from abnormality of mitochondrial function
5% have familial SOD1 mutation
Amyotrophic lateral sclerosis (ALS)
Most common (<80%)
Loss of motor neurons in motor cortex and anterior horn of cord (UMN + LMN)
Progressive bulbar palsy (PBP)
10-20%
CN9-12 (LMN)
Progressive muscular atrophy (PMA)
<10%
Anterior horn lesion (LMN)
Affects distal muscle groups before proximal
Primary lateral sclerosis (PLS)
Loss of bets cells in motor cortex (UMN)
Spastic leg weakness, pseudobulbar palsy, no cognitive decline
MND Px
ALS - UMN+LMN
Weakness, LMN wasting/fasciculations - usually one limb
Cramps
Split hand sign - thenar wasting, thumb side of hand seems adrift
Wrist and foot drop
UMN signs - brisk reflexes, positive Babinski, spasticity
PMA - LMN Everything goes down Muscle tone reduced - flaccid Muscle wasting Fasciculation Reflexes depressed/absent Usually starts in one limb, gradually spreads Affects distal muscles before proximal
PBP - LMN
Dysarthria, dysphagia, nasal regurgitation of fluids, choking
LMN lesion of tongue - flaccid, fasciculating, jaw jerk normal/absent, speech quiet, hoarse, nasal
PLS - UMN
Everything goes up
Spasticity
Brisk reflexes - tendon and jaw reflexes, positive Babinski
Upper limb extensors weaker than flexors, lower limb flexors weaker than extensors, finer movt impaired
Velocity dependent spasticity - clasp knife
Less prominent muscle wasting
FTD in 25%
Weakness and atrophy spreads from start to other parts of body
MND DDx
MS and polyneuropathies - have sensory loss, sphincter disturbance
MG - eye movts affected
Diabetic amyotrophy, GBS, spinal cord tumours
MND Ix
Clinical findings
Brain/cord MRI, LP - exclude structural causes
Nerve conduction studies (NCS), electromyography (EMG) - shows denervation of muscles
MND Mx
Oral riluzole (inhibits glutamate release, thought to play role in cell death)
Drooling - oral propantheline (anti-muscarinic) or oral amitriptyline (dries mouth)
Dysphagia - blend food, NG tube
Spasm - oral baclofen (CNS depressant, skeletal muscle relaxant)
Analgesia - NSAIDs, opioids
Palliative MDT care (death from resp failure in 3yrs)
Multiple sclerosis
Autoimmune inflammatory disorder of CNS - multiple plaques of demyelination in brain and spinal cord, occurring sporadically over years
MS patho
T cell mediated, oligodendrocytes targeted, auto-ABs against myelin created
Multiple areas of scar tissue form along neurons - slow/block transmission
acute attacks, period of remission where there is remyelination, but is less efficient, temp dependent
Types - relapsing/remitting, 2 progressive, 1 progressive
RFs - race (caucasian), genetics (HLADR2), FHx, maybe low sunlight and vit D
MS Px
Usually monosymptomatic
Unilateral optic neuritis - pain on eye movt, decreasing central vision
Symptoms may worsen with heat, eg bath, exercise
sensory
dysaesthesia - unpleasant sensation when touched
pins/needles
decreased vibration sense
trigeminal neuralgia
GI - dysphagia, constipation
Eye - diplopia, hemianopia, optic neuritis, visual phenomena, pupil defects
motor
spastic weakness
transverse myelitis - weakness/paralysis of both legs
Cerebellum - trunk/limb ataxia, intention tremor, scanning speech (monotonous), falls
sexual/GU
erectile dysfunction
anorgasmia, urine retention, incontinence
Malaise, N+V, positional vertigo, seizures, aphasia, meningism
MS Ix
Clinical Dx with McDonald’s criteria - 2+ attacks affecting different parts of CNS
Exclude differentials - FBC, inflammatory markers, U+E, glucose, HIV serology, auto-ABs, Ca, vit B12
MRI brain, spinal cord
LP - oligoclonal IgG bands
Electrophysiology - visual evoked potential studies
MS Mx
Exercise, stop smoking, reduce stress
Dimethyl fumarate (decreases worsening episodes), MABs
Methylprednisolone - for relapses
Spasticity - baclofen/gabapentin
Tremor - botox
Urgency/frequency - self-catheterisation/tolterodine
Fatigue - amantadine, CBT
Stem cell transplant
Myasthenia gravis
autoimmune disease with ABs against nicotinic ACh receptors in NMJ
MG patho
If <50yo, commoner in women, associated with other autoimmune disease - pernicious anaemia, SLE, RA, thymic hyperplasia
IF >50yo, commoner in men, associated with RA, SLE, thymic atrophy/tumour
Transient MG sometimes caused by penicillamine tx for Wilson’s
Destruction of AChR, immune complex deposition, blocks excitatory effect of ACh on nicotinic receptors - muscle weakenss
MG Px
Increasing muscular fatigue
Muscle groups affected in order: extra-ocular, bulbar, face, neck, trunk
Proximal limb muscles, speech, facial expression commonly affected
Ptosis, diplopia, myasthenic snarl
Resp difficulties
Tendon reflexes normal, may be fatigable
Ask to count to 50, voice becomes less audible
Hold finger up high, ask patient to look up, after a while will not be able to keep eyes raised
Worsened by - pregnancy, hypokalaemia, infection, emotion, drugs
MG DDx
Other causes of generalised muscle weakness - MS, hyperthyroidism, acute GBS
Lambert-Eaton myasthenic syndrome (defective ACh release, weakness tends to improve after exercise)
MG Ix
Serum anti-AChR, if negative look for anti-MuSK (muscle specific tyrosine kinase)
EMG, NCS
CT thymus - hyperplasia, atrophy, tumour
MG Mx
Anti-cholinesterase, so more ACh remains in NMJ - oral pyridostigmine
Immunosuppression - prednisolone, azathioprine, methotrexate
Thymectomy
MG Cx
Myasthenic crisis - weakness of resp muscles during relapse, tx plasmapheresis (AB removal), IV Ig
aspiration pneumonia, acute resp failure, ADL restrictions
Carpal tunnel syndrome
Compression of median nerve as it passes through carpal tunnel in wrist
CTS patho
entrapment of median nerve - anything that causes swelling/compression of tunnel
DM, pregnancy, amyloidosis, obesity, RA, acromegaly, hypothyroidism
CTS Px
Intermittent symptoms, gradual onset
Aching in hand and arm, esp at night, can wake patient up
Paraesthesia in thumb, index, middle, 1/2 ring finger and palm
Relieved by dangling hand over bed
May be sensory loss, weakness of abductor pollicis brevis +/- wasting of thenar eminence
Light touch, 2-point discrimination and sweating may be impaired
CTS DDx
peripheral neuropathy, MND, MS
CTS Ix
Electroneurography (ENG)
Electromyography (EMG)
Phalen’s test - patient can only maximally flex wrist for 1min and will produce symptoms of carpal tunnel
Tinel’s test - tapping on nerve at wrist induces tingling
CTS Mx
Wrist splint at night
Local steroid injection
Decompression surgery
Sciatica
L5/S1 root compression
Sciatica causes
Spinal - disc prolapses, spinal stenosis, spondylolisthesis
Piriformis syndrome, pregnancy, trauma, back injury
OA
Sciatica Px
signs unilateral weak plantar flexion absent right ankle jerk decreased sensation over lateral edge and sole of right foot
symptoms
pain in buttock, back of thigh, lateral aspect of little toe (sciatic nerve distribution)
Sciatica Ix
MRI/CT
Examination - straight leg raise test (gently raise leg, if pain then positive)
Sciatica Mx
Analgesia
Surgical decompression
Olfactory nerve palsy (CN1)
anosmia - can’t smell
optic nerve palsy (CN2)
visual defects depend on location of lesion
oculomotor nerve palsy (CN3)
ptosis
fixed dilated pupil (loss of psym outflow)
Eye looks down and out
causes - raised ICP, diabetes, HTN, GCA, berry aneurysm
trochlear nerve palsy (CN4)
Innervates superior oblique
Palsy results in head tilt to correct extortion that results in diplopia on looking down
Causes - trauma to orbit (rare)
abducens nerve palsy (CN6)
innervates LR, eye will be adducted, looking in
Causes - MS, Wenicke’s encephalopathy, pontine stroke (presents with small fixed pupils +/- quadriparesis)
CN3,4,6 palsy
non-functioning eye
Causes - stroke, tumours, Wernicke’s encephalopathy
Trigeminal nerve palsy (CN5)
jaw deviates to side of lesion
loss of corneal blink reflex
Causes - trigeminal neuralgia, herpes zoster, nasopharyngeal cancer
Facial nerve palsy (CN7)
facial droop and weakness
Forehead sparing if lesion is central, before facial nerve nucleus
Causes - Bell’s palsy, fractures of petrous bones, middle ear infections, inflammation of parotid gland (facial nerve passes through)
Tx with steroids
vestibulocochlear nerve palsy (CN8)
hearing impairment, vertigo, lack of balance
Causes - surrounding tumour, skull fracture, toxic drug effects, ear infections
glossopharyngeal (CN9) and vagus (CN10) palsy
gag reflex issues, swallowing issues, vocal issues
causes - jugular foramen lesion
accessory nerve lesion (CN11)
SCM and trapezius
can’t shrug shoulder or shake head
hypoglossal nerve palsy (CN12)
tongue deviates towards side of lesion
Spinal cord tract
Corticospinal
motor
descending UMN
decussates at medulla
DCML
ascending sensory tract
fine touch, proprioception, vibration, 2-point discrimination
decussates at medulla
Spinothalamic
ascending sensory
pain, temp, crude touch
decussates almost immediately in spinal cord
Brown-Sequard Syndrome
Hemisection of spinal cord
Causes Space-occupying lesions Intervertebral disc prolapses Vertebral bone fractures Trauma - GSW, knife Infectious - HIV MS
Px
Level of lesion:
- ipsilateral spinothalamic dysfunction - loss of temp, pain, pressure sense
Below lesion:
- ipsilateral corticospinal dysfunction - loss of motor function (weakness)
- ipsilateral DCML dysfunction - loss of fine touch, proprioception, vibration, 2-point discrimination
- contralateral spinothalamic dysfunction - loss of temp, pain, pressure
Overall - ipsilateral loss of fine touch, proprioception, motor, contralateral loss of pain, temp, crude touch
Ix
MRI spine
Mx
physical and occu therapy
Steroids - reduce swelling inflammation
Paraplegia
paralysis of both legs - always spinal cord lesion
Hemiplegia
paralysis of one side of body - brain lesion
UMN signs
signs contralateral to lesion - indicates lesion is above anterior horn cell - in spinal cord, brainstem, motor cortex
Increased muscle tone - spastic paralysis, velocity dependent, non-uniform, clasp-knife
Weakness - flexors weaker than extensors in legs, extensors weaker than flexors in arms
Hyperreflexia - reflexes increased, are brisk
LMN signs
Signs ipsilateral to lesion
decreased muscle tone, flaccid paralysis (nerve to muscle cut, will go floppy for life…)
wasting/atrophy, fasciculations
reflexes reduced/absent
Parkinson’s disease
degenerative movt disorder caused by reduction in dopamine in substantia nigra
PD patho
associated with dementia and depression
combination of environ, genetics, oxidative stress, mito dysfunction
progressive loss of dopaminergic neurons from pars compacta of SN in midbrain - less dopamine, thalamus inhibited - decrease of movt
neural inclusions present
RFs- FHx, environmental factors
PD Px
gradual, asymmetrical onset of symptoms, commonly present with impaired dexterity
anosmia, depression, anxiety, aches and pains, REM sleep disorders, urinary urgency, hypotension and constipation
Tremor
worse at rest, asymmetrical
issue with repetitive hand movts, worsening in rhythm the longer attempted
Rigidity
increased tone in limbs and trunk
limb resists passive movt throughout (as opposed to UMN lesion spasticity - clasp knife)
Bradykinesia
slow to initiate movt
reduced blink rate, monotonous hypophonic speech, writing smaller, difficulty with fine movt, narrow gait, reduced asymmetrical arm swing, problems with balance, stooped posture, shuffling steps
expressionless face
PD DDx
benign essential tremor, multiple cerebral infarcts, drug induced, Wilson’s disease, trauma, HD
PD Ix
Clinical dx, can confirm by levodopa response
CT/MRI head
PD Mx
Oral levodopa, with deoxycarbolase inhibitor (co-careldopa / co-beneldopa) which prevents peripheral conversion of l-dopa to dopamine (cannot cross BBB)
Dopamine agonists - oral ropinirole / oral pramipexole
Mono oxidase B (MAO-B) inhibitors - oral selegiline / oral rasagiline
Catechol-O-methyltransferase (COMT) inhibitors - oral entacapone / oral tolcapone
COMT and MAO-B break down dopamine
Surgical - ablation of overactive basal ganglia circuits, eg subthalamic nuclei
PD Cx
Depression, dementia, psychosis
SSRI - oral citalopram
Anti-psychotic - oral quetiapine
Radiculopathy
pinched nerve - compression of nerve root and LMN
Mononeuropathy
disease affecting single nerve - peripheral/cranial nerve
causes usually local - eg trauma, entrapment, tumour
Common - CTS, ulnar neuropathy, peroneal neuropathy, cranial neuropathies
Mononeuritis multiplex
2+ peripheral nerves affected (separate areas)
when causes tend to be systemic - WARDS PLC Wegener's granulomatosis AIDs/amyloid RA DM Sarcoidosis PAN Leprosy Carcinoma
Polyneuropathy
disease of many nerves
diffuse, symmetrical, usually starts peripherally
Can be sensory/motor/autonomic/mixed
Mostly motor - GBS, lead poisoning, Charcot-Marie-Tooth syndrome
Mostly sensory - DM, renal failure, leprosy
Px SENSORY numbness, paraesthesia glove+stocking loss of dexterity maybe signs of trauma (not noticed by patient)
MOTOR
progressive
weak/clumsy hands
difficulty in walking, breathing, weakness, wasting
6 mechanisms that can cause nerve malfunction
Demyelination
Axonal degeneration - causes nerve to die back from periphery
Compression
Infarction
Infiltration - by inflammatory cells
Wallerian degeneration - nerve fibre cut, distal part of axon separated from cell body dies
Peripheral neuropathies Px
symptoms
sensory - loss of pain, warmth/cold, proprioception, balance, pressure, vibration (depends on fibre affected)
motor - muscle cramps, weakness, fasciculations, atrophy, ataxia, high arched feet from excessive atrophy
signs
- symmetrical sensorimotor - commonest neuropathy, starts distally, initially sensory, then sensorimotor
- asymmetrical sensory - patchy, dorsal root ganglia affected, uncommon - paraneoplastic, Sjogrens, coeliac disease
- asymmetrical sensorimotor - mononeuritis multiplex, very uncommon - vasculitis
Peripheral neuropathy Ix
H+E
Neurophysiological examination - nerve conduction studies/quantitative sensory test
Peripheral neuropathy Mx
Anti-neuralgic for pain - gabapentin, amitriptyline, pregabalin
Cramps - quinine
Spinal cord compression
compression can occur in any part of spinal cord
Causes
spondylosis (degeneration of spine), disc prolapse, spondylolisthesis, tumour, stenosis, abscess, TB, trauma, infection
RFs
osteoporosis, trauma, tumour, RA, ankylosing spondylitis
Px
At level of lesion - back pain, nerve root pain, numbness, paraesthesia, LMN signs
Below lesion - UMN signs
Sphincter disturbance, loss of bladder and bowel control
Ix
MRI
Mx
Surgical - decompressive laminectomy
Dexamethasone/chemo/radio if malignancy
Stroke
disruption of blood supply to the brain, leading to neurological deficit from focal infarction
Stroke patho
Ischaemic/infarction (80%) loss of blood flow, lack of oxygen - thrombosis in situ - emboli from atheroma (carotid bifurcation commonly) - heart emboli - AF, valve disease, IE, fat emboli after long bone fracture - large artery stenosis - watershed stroke - drop in BP - venous sinus thrombosis (1%)
Haemorrhage (17%)
Bleeding in CNS - trauma, aneurysm rupture, thrombolysis, anticoagulation, carotid artery dissection, SAH, HTN -> microaneurysm rupture
RFs
HTN, smoking, DM, heart disease, PAD, post-TIA, polycythaemia, combined OCP, hyperlipidaemia, exess alcohol
Stroke Px
Worse at onset
Distinguish between the two (not reliable)
Haemorrhagic - meningism, severe headache, coma
Ischaemic - carotid bruit, AF, past TIA, IHD
FAST
ACA Leg weakness > arm weakness leg sensory disturbances gait apraxia truncal ataxia incontinence drowsiness akinetic mutism - stuporous state
MCA
contralateral arm and leg weakness, sensory loss
hemianopia
aphasia (cannot understand/produce speech)
dysphasia (deficiency in speech generation)
facial droop
PCA
contralateral homonymous hemianopia
cortical blindness (brain tissue causes blindness, eye is healthy)
visual agnosia (cannot interpret visual info)
prosopagnosia - cannot see faces
Posterior circulation brainstem, cerebellum locked in syndrome - aware, cannot respond motor deficits - hemiparesis, tetraparesis, facial paralysis dysarthria, speech impairment vertigo, N+V visual disturbance altered consciousness
Lacunar stroke 25% basal ganglia, internal capsule, thalamus, pons unilateral weakness +/- sensory deficit ataxic hemiparesis cerebellar and motor symptoms
Stroke DDx
head injury, hypo/hyperglycaemia, SDH, hepatic encephalopathy
Stroke Ix
Head CT
BP, ECG - look for AF
Bloods - FBC (polycythaemia), glucose, ESR
Stroke Mx
ABCDE
Aspirin (once haemorrhagic excluded)
Thrombolytic drugs - alteplase
Thrombectomy - surgical removal
Haemorrhagic
Surgery
Mannitol for raised ICP
Control HTN
Prevention Aspirin, clopidogrel Simvastatin AF tx HTN tx
Transient ischaemic attack
temporary inadequacy of circulation to part of brain
<24hrs, most <30 mins
TIA causes
atherothromboembolism
cardioembolism - post-MI, valve disease, AF
hyperviscosity - polycythaemia, sickle cell, myeloma
Vasculitis
Hypoperfusion - cardiac dysrhythmia, postural hypotension
TIA RFs
HTN, smoking, DM, heart disease, PAD, polycythaemia, hyperlipidaemia
TIA Px
sudden loss of function, lasts minutes
FAST
Anterior circulation
weak, numb contralateral leg, maybe similar arm symptoms
hemiparesis
hemisensory disturbance
dysphagia
amaurosis fugax - temporary loss of vision, eg emboli in retinal, ophthalmic, ciliary blood flow
Posterior circulation diplopia vertigo vomiting choking, dysarthria ataxia hemisensory loss hemianopia LOC transient global amnesia tetraparesis (muscle weakness at all 4 extremities)
TIA Ix
Bloods - FBC (polycythaemia), ESR (vasculitis), glucose, creatinine, electrolytes, cholesterol
Carotid artery doppler USS - look for atheroma/stenosis
MRI/CT angiography
ECG - AF or MI ischaemia
Calculate ABCD2 score - risk of stroke after TIA
TIA Mx
Control CV risk factors - ACEi/ARB, simvastatin, DM, stop smoking
Aspirin, clopidogrel
If CV source of emboli - heparin, warfarin
Carotid endarterectomy - correct stenosis
