Neurology Flashcards
UMN lesion features
Weakness Spasticity (increased tone, clasp knife rigidity) Hyperreflexia Positive babinski (upgoing plantars) Clonus
LMN lesion feature
Weakness Wasting Fasciculation Hypotonia/flaccid paralysis Hyporeflexia
Sensory deficits and their location in the cord
Pain and temperature - small fibres in peripheral nerves and anterolateral spinothalamic tract in the cord and brainstem
Proprioception and vibration - large fibres in peripheral nerves and dorsal column medial lemniscus of the cord
Features of lesion in internal capsule and corticospinal trct
contralateral hemiparesis (UMN), generalised contralateral sensory loss
Brainstem lesion features
Ipsilateral cranial nerve palsy and contralateral hemiplegia
Lateral brain stem lesion - dissociated and crossed sensory loss with loss of pain and temperature on the side of the face ipsilateral to the lesion, and contralateral arm and leg sensory loss
Cord lesion features
Paralysis below the level of the lesion. LMN signs at the level of the lesion and UMN signs below the lesion. A sensory level is the hallmark.
Peripheral neuropathy features
Distal weakness, sensory loss is typically worse distally
Involvement of a single nerve may occur with trauma/entrapment
Sensory loss with mononeuropathies will follow dermatomal territories
What do the internal carotid arteries supply
Anterior two-thirds of the cerebral hemispheres and the basal ganglia (via the lenticulostriate arteries)
Which arteries make up the circle of willis?
Internal carotids (anteriorly), basilar artery (posteriorly, formed by joining the vertebral arteries), anterior cerebral arteries, anterior communicating arteries, posterior communicating arteries, posterior cerebral arteries
Headache red flags
- Immunocompromised
- <20 with malignancy
- Vomiting without an obvious cause
- Worsening headache + fever
- Sudden onset headache reaching max intensity within 5 mins (thunderclap)
- New onset neuro deficit
- New onset cognitive dysfunction
- Change in personality
- Impaired consciousness
- Recent head trauma
- Headache triggered by cough/sneeze/ exercise
- Orthostatic headache
- Symptoms suggestive of giant cell arteritis or acute narrow-angle glaucoma
- Substantial change in the characteristics of their headache
Differentials for rapid onset headache
SAH Meningitis Encephalitis Post-coital headache Head trauma
Differentials for subacute/gradual onset headache
Venous sinus thrombosis Sinusitis Giant cell arteritis Tropical illness (malaria) Intracranial hypotension Idiopathic intracranial hypertension Glaucoma
Differentials for chronic headache
Migraine Tension headache Medication overuse headache Cluster headache Visual defects
Cluster headache risk factors
Male
Smokers
Alcohol may trigger an attack
Cluster headache features
Pain typically once/twice a day, lasting 15min-2hrs
The clusters typically last 4-12 weeks
Intense sharp stabbing pain around one eye (always affects same eye in one cluster)
Patient is restless and agitated during attack
Accompanied by redness, lacrimation and lid swelling
Nasal stuffiness
Miosis and ptosis in some
Management of cluster headache
Acute: 100% oxygen, subcut triptan
Prophylaxis: verapamil
Migraine features
Severe, unilateral throbbing headache
Nausea, photophobia, phonophobia
May last up to 72 hours
May be precipitated by an aura: visual, progressive, lasts 5-60mins, transient hemianopic disturbance or a spread of scintillating scotoma
Common triggers for a migraine
Tiredness, stress, alcohol, COCP, hunger, dehydration, cheese, chocolate, red wines, citrus fruits, menstruation, bright lights
Migraine diagnostic criteria
At least 5 attacks fulfilling the following criteria:
= Headache attacks lasting 4-72 hours
= Headache has at least two of the following: unilateral, pulsating, moderate/severe pain, aggravated by physical activity
= During headache at least one of: nausea and/or vomiting, photophobia and phonophobia
= Not attributed to another disorder
Acute treatment of migraines
First line: combination therapy with an oral triptan and an NSAID/paracetamol
-Consider nasal triptan rather than oral in children aged 12-17
Migraine prophylaxis
Given to patients who experience 2+ attacks/month
First line: Topiramate or propranolol (patient preference)
Propranolol for women of child bearing age
Second line: up to 10 sessions of acupuncture
Management of migraines during pregnancy
1g paracetamol is first line
NSAIDs can be used second-line in first and second trimester
Avoid aspirin and opioids
Absence seizures
- Epidemiology
- Features
- EEG
- Management
Generalised epilepsy, most common in children (4-8y, girls>boys)
Features: lasts a few seconds with quick recovery, may be provoked by hyperventilation or stress, child is usually unaware of the seizure, may occur many times a day
EEG: bilateral, symmetrical 3Hz spike and wave pattern
Management: sodium valproate and ethosuximide are first line
Carbamazepine
- uses
- MoA
- adverse effects
First-line for partial seizures
Also used in trigeminal neuralgia and bipolar disorder
MoA: binds to sodium channels increasing their refractory period
Adverse effects: P450 inducer, SIADH (hyponatraemia), dizziness, ataxia, drowsiness, headache, diplopia, Steven-Johnson, leucopenia, agranulocytosis
Differentials for non-epileptic recurrent seizures
Febrile convulsions
Alcohol withdrawal seizures
Psychogenic non-epileptic seizures
Alcohol withdrawal seizures
-who, when, how to reduce risk
Occurs in patients with history of alcohol excess who suddenly stop drinking
Typically occurs 36 hours after stopping drinking
Patients are often given benzodiazepines (chlordiazepoxide) following alcohol cessation to reduce risk
What are focal/partial seizures and how are they classified
Starts in a specific area, on one side of the brain
Level of awareness varies (focal aware, or focal impaired awareness)
Can be further classified as being motor (eg. jacksonian march), non-motor (eg. deja vu) or having other features (eg. aura)
Generalised seizures
- what are they
- consciousness
- subclassification
- specific types
Both sides of the brain are involved at onset
Consciousness lost immediately
Can be subdivided into motor (eg. tonic-clonic) and non-motor (eg. absence)
Specific types: tonic-clonic, tonic, clonic, typical absence, myoclonic, atonic
What are focal to bilateral seizures?
Starts on one side of the brain in a specific area before spreading to both lobes
Features of generalised seizures
May have an aura beforehand
During seizure: tongue biting, urine incontinence
Postictal phase: drowsiness, tiredness for about 15mins
Investigations following a seizure
EEG
MRI
Antiepileptics
Antiepileptics are started following a second epileptic seizure
Sodium valproate is usually first line for generalised seizures
Carbamazepine is generally first line for focal seizures
Lamotrigine can also be used first line for focal seizures, and is second line for most generalised seizures. Suitable alternative to valproate in women of child bearing age
DVLA and seizures
No driving for 6m following a seizure
Must be seizure free for 12m if patient has established epilepsy
Sodium valproate
- Uses
- MoA
- Adverse effects
- First line for generalised seizures
- Increases GABA activity
- SE: teratogenic, weight gain, P450 inhibitor, alopecia, ataxia, tremor, hepatitis, pancreatitis, thrombocytopenia
Lamotrigine
- Uses
- MoA
- Adverse effects
- Second-line for a variety of generalised and partial seizures
- MoA: sodium channel blocker
- SE: Stevens-Johnson syndrome
Phenytoin
- Uses
- MoA
- Adverse effects
- Used in status epilepticus
- MoA: binds to sodium channels, increasing their refractory period
- SE: P450 inducer, dizziness, ataxia, gingival hyperplasia, drowsiness, coarsening of facial features, hirsutism, megaloblastic anaemia, peripheral neuropathy, osteomalacia, lymphadenopathy
Managing a patient during a seizure (not status epilepticus)
Protect form injury - cushion the head, remove glasses, remove harmful objects nearby
Do not restrain or put anything in the mouth
Most seizures terminate spontaneously
If a seizure has not terminated after 5-10 mins then patient should be given a benzodiazepine (IV lorazepam, buccal midazolam, PR diazepam). Patients should have these with them in the community, and family members should be taught how to administer them.
If patient continues to fit despite these measures = status epilepticus
When seizure stops, check airways and put in recovery position, and observe until they have recovered fully
West’s syndrome
- what is it
- what happens
- EEG
- Prognosis
- Management
Infantile spasms beginning at 4-6m of life (M>F)
Flexion of head, trunk and limbs -> extension of arms (Salaam attack), lasts 1-2secs, repeats up to 50 times
Progressive mental handicap
EEG: hypsarrhythmia
Usually secondary to neurological abnormality
Poor prognosis
Give vigabatrin/ steroids
Features of focal epileptic seizures based on location
- temporal
- frontal
- parietal
- occipital
- Temporal (HEAD): hallucinations, epigastric rising/emotional, automatisms (lip smacking, grabbing, plucking), deja vu/dysphasia post-ictal
- Frontal: head/leg movements, posturing, post-ictal weakness, jacksonian march
- Parietal: paraesthesia
- Occipital: floaters/ flashes
Features favouring psychogenic non-epileptic seizures over a true epileptic seizure
Pseudoseizure: pelvic thrusting, family member with epilepsy, much more common in females, crying after seizure, dont occur when alone, gradual onset
True epileptic seizure: tongue biting, raised serum prolactin
Management of status epilepticus in the hospital
Secure airway + 100% oxygen
Assess cardioresp function
Check blood glucose, FBC, calcium, U+E, LFT, +/- tox screen, anticonvulsant levels
Secure IV access
Anaesthetist should be at the bedside if patient has been seizing for 20min
IV bolus of lorazepam 4mg
Repeat if no response after 10-20min
Thiamine 250mg IV over 30 min if alcoholism or malnutrition suspected
Give glucose 50ml 50% IV, unless glucose known to be normal
Treat acidosis if severe (contact ICU)
Correct hypotension with fluids
IV phenytoin infusion if seizure continues, monitor ECG and BP
If seizure continues after 60-90min, ventilation and propofol infusion for rapid sequence induction is needed (ITU)
Investigations during status epilepticus
Bedside glucose
Once treatment has started do the following: lab glucose, ABG, U+E, calcium, FBC, ECG
Consider anticonvulsant levels, tox screen, LP, culture blood and urine, EEG, CT, carbon monoxide level
Pulse oximetry, cardiac monitor
Tension type headache characteristic features
Tight band around the head or a pressure sensation
Symptoms are bilateral (migraine = unilateral)
Tends to be a lower intensity than a migraine
Not associated with aura, N+V or aggravated by activity
May be related to stress
May co-exist with migraine
Chronic tension type headache = tension headache occurring on 15+ days per month
Management of tension type headaches
Acute: aspirin, paracetamol or NSAID
Prophylaxis: up to 10 sessions of acupuncture over 5-8 weeks
Definition of a transient ischaemic attack
A transient neurological dysfunction secondary to ischaemia without infarction.
Lasts less than 24 hours.
What is a crescendo TIA?
TIAs often precede a full stroke.
A crescendo TIA is where there are two or more TIAs within a week. This carries a high risk of progressing to a stroke
When to suspect a stroke?
SUDDEN onset of neurological symptoms = vascular cause
Typically asymmetrical: sudden weakness of limbs, sudden facial weakness, sudden dysphasia, sudden visual or sensory loss
Risk factors for a stroke
Cardiovascular disease Previous stroke or TIA AF Carotid artery disease Hypertension Diabetes Smoking Vasculitis Thrombophilia Combined oral contraceptive pill Anticoagulation (-haemorrhagic)
Tool used in the community for recognising a stroke
FAST Face Arms Speech Time to call 999
Tool used in A+E for recognising a stroke
ROSIER
‘Recognition of stroke in emergency room’
Exclude hyperglycaemia first, then assess the following:
LOC or syncope = -1
Seizure activity = -1
Acute onset of asymmetrical face weakness = +1
Acute onset of asymmetrical arm weakness = +1
Acute onset of asymmetrical leg weakness = +1
Acute onset of speech disturbance = +1
Acute onset of visual field defect = +1
Stroke is likely if the patient scores anything above 0
Scoring tool used for patients with TIA
ABCD2
Used for assessing patients with a suspected TIA to estimate their risk of subsequently having a stroke. A higher score suggests a higher risk of stroke within the following 48 hours.
NICE no longer recommend using this.
Age >60 (1)
Blood pressure >140/90 (1)
Clinical features: unilateral weakness (2), dysphasia without weakness (1)
Duration: >60min (2), 10-60min (1), <10min (0)
Diabetes (1)
Classification of strokes
Oxford stroke classification
The following criteria is assessed:
- Unilateral hemiparesis and/or hemisensory loss of the face, arm and leg
- Homonymous hemianopia
- Higher cognitive dysfunction (eg. dysphasia)
Total anterior circulation infarct (TACI): involves middle and anterior cerebral arteries. All 3 of above criteria present.
PACI: involves smaller arteries of anterior circulation. 2 of above criteria present.
POCI: involves vertebrobasilar arteries. Presents with 1 of the following:
- Cerebellar or brainstem syndromes
- LOC
- Isolated homonymous hemianopia
Lacunar: involves perforating arteries around the internal capsule, thalamus and basal ganglia.
Presents with 1 of the following:
1. unilateral weakness and/or sensory deficit of face and arm, arm and leg, or all three
2. Pure sensory stroke
3. Ataxic hemiparesis
Management of ischaemic stroke
Immediate CT brain within 1hr to exclude haemorrhage.
If thrombectomy might be indicated, perform CT contract angiography after the initial non-enhanced CT
Aspirin 300mg stat (after CT) and continue for 2 weeks, then switch to lifelong clopidogrel 75mg OD
Thrombolysis with alteplase if CT excludes haemorrhage
Thrombectomy also considered in some patients
Keep NBM until swallow screen is done
Maintain BMs between 4-11
Start on statin if cholesterol >3.5 (dealy until after 48 hours due to risk of haemorrhagic transformation)
If patient has AF: dont start anticoag until 14 days have passed
Management of suspected TIA
Stat aspirin 300mg and continue for 14 days then switch to clopidogrel 75mg
Carotid endarterectomy required within 2 weeks if carotid artery is 70-99% stenosed and operative risk is acceptable
Stop driving for 1 month
If patient has had >1 TIA (crescendo) or has suspected cardioembolic source or severe carotid stenosis: discuss admission to stroke specialist
If patient has had suspected TIA in last 7 days: arrange urgent assessment within 24hrs by stroke specialist (TIA clinic)
If patient has had suspected TIA more than a week ago: refer for specialist assessment ASAP within 7 days
Management of haemorrhagic stroke
CT confirms haemorrhage
Neurosurgical consultation should be considered
Most patients arent suitable for surgery, management si therefore supportive
Stop anticoags and antithrombotics
Reverse any anticoagulation
Criteria for thrombolysis
Absolute contraindications
Relative contraindications
Must be administered within 4.5 hours of onset of stroke symptoms
Haemorrhage must be definitively excluded
Absolute contraindications: previous intracranial haemorrhage, seizure at onset of stroke, intracranial neoplasm, suspected SAH, stroke or traumatic brain injury in preceding 3m, LP in preceding 7 days, GI haemorrhage in preceding 3 weeks, active bleeding, pregnancy, oesophageal varices, uncontrolled HTN >200/120
Relative contraindications: concurrent anticoag, haemorrhage diathesis, active diabetic haemorrhagic retinopathy, suspected intracardiac thrombus, major surgery/trauma in preceding 2 weeks
Criteria for mechanical thrombectomy
Pre-stroke function status of less than 3 on modified Rankin scale
Score of >5 on NIHSS
Offer thrombectomy as soon as possible and within 6 hours of symptom onset, together with IV thrombolysis (within 4.5hours), to people who have: acute ischaemic stroke, and confirmed occlusion fo proximal anterior circulation demonstrated by CT angiography (or MR angiography)
Offer thrombectomy as soon as possible to people who were healthy/well between 6-24 hours previously: who have acute ischaemic stroke and confirmed occlusion of proximal anterior circulation demonstrated by CTA, and if there is the potential to salvage brain tissue as shown on CT perfusion or diffusion-weighted MRI
Consider thrombectomy with IV thrombolysis ASAP for people last known to be well up to 24 hours previously: who have acute ischaemic stroke and confirmed occlusion of proximal posterior circulation demonstrated by CTA, and if there is potential to salvage brain tissue as shown on CT perfusion or diffusion-weighted MRI
Secondary prevention of ischaemic stroke
Clopidogrel 75mg OD lifelong
Carotid doppler US +/- CT/MRI angiography -> Carotid endarterectomy for patients who have carotid stenosis >70% (ECST criteria)
Barthel’s index of activities of daily living
Assesses 10 ADLs: bowels, bladder, grooming, toilet use, feeding, transfer, mobility, dressing, stairs, bath/shower
Stroke mimics
Group 1 – readily identifiable on brain imaging
- Subdural haematomas
- Tumours
- Brain abscesses
- MS – may present acutely with focal neurology
Group 2 – identifiable after general assessment based on clinical knowledge
- Syncope syndrome
- BPPV
- Vestibular neuritis
- Transient global amnesia
Group 3 – distinguishable after specialist stroke assessment and brain imaging
- Migraine with aura
- Focal seizures
- Functional syndrome
Stroke features by anatomy
- anterior cerebral artery
- middle cerebral artery
- posterior cerebral artery
- Ophthalmic artery
- Basilar artery
- Anterior cerebral artery: contralateral hemiparesis and sensory loss (lower limb > upper limb because of homunculus)
- Middle cerebral artery: contralateral hemiparesis and sensory loss (upper limb > lower limb because of homunculus), contralateral homonymous hemianopia, aphasia
- Posterior cerebral artery: contralateral homonymous hemianopia with macular sparing, visual agnosia
- Ophthalmic artery: amaurosis fugax
- Basilar artery: locked in syndrome
Stroke syndromes:
- Webers syndrome
- Wallenberg syndrome
- Lateral pontine syndrome
- Webers: branches of posterior cerebral artery that supply midbrain. Ipsilateral CNIII palsy, contralateral weakness of upper and lower limbs
- Wallenbergs: lateral medullary syndrome. Posterior inferior cerebellar artery. Ipsilateral facial pain and temp loss, contralateral limb/torso pain and temp loss, ataxia, nystagmus
- Lateral pontine: anterior inferior cerebellar artery. Symptoms similar to wallenbergs but ipsilateral facial paralysis and deafness
MDT input for stroke treatment
Doctors Nurses SALT Nutrition and dietetics PT OT Social services Optometry and ophthalmology Psychology Orthotics
Non-contrast CT features of early ischaemia
Increased density of the relevant blood vessel due to the presence of clotted blood
Loss of grey-white matter differentiation, hypodensity of cortical tissue
Obscuration of the lentiform nucleus (seen in MCA occlusion)
National Institute of Health Stroke Scale
A tool used to assess the severity of a stroke.
1) Level of consciousness:
a) Level of consciousness (level of alertness) (0-3)
b. LOC questions (verbal) (0-2)
c. LOC commands (visual and motor) (0-2)
2) Best gaze (0-2)
3) Visual fields (0-3)
4) Facial palsy (0-3)
5) Arm motor (0-4)
6) Leg motor (0-4)
7) Limb ataxia (0-2)
8) Sensory (0-2)
9) Best language (0-3)
10) Dysarthria (0-2)
11) Extinction and inattention, formerly called neglect (0-2)
0 = no stroke symptoms 1-4 = minor stroke 5-15 = moderate stroke 16-20 = moderate/ severe 21-42 = severe stroke
Complications of thrombolysis
Extracerebral haemorrhage-> thread pulse, ↓ BP, melaena, distended abdo
New headache
Acute hypertension
Nausea and vomiting
Complications of stroke
Recurrent stroke and extension of stroke
Raised intracranial pressure – haematoma expansion, malignant oedema, haemorrhagic transformation, hydrocephalus
Infection – chest infections due to aspiration, UTIs due to incomplete bladder emptying from either constipation or bed bound position
Complications of immobility - VTE, constipation, bed sores
Mood and cognitive dysfunction (this can affect compliance and rehabilitation)
Post stroke pain and fatigue - spasticity, joint dislocation or central/neuropathic pain, poor sleep, medications, inherent result of brain cell damage
Spasticity, contractures and secondary epilepsy
Premature death – usually related to post-stroke complications rather than the stroke itself
Modified Rankin Scale
Scale used for measuring the degree of disability following a stroke, determining the need for PT/OT therapy and the degree of care required
0 – no symptoms
1 – no significant disability. Able to carry out usually activities, despite some symptoms
2 – Slight disability. Able to look after own affairs without assistance, but unable to carry out all previous activities
3 – moderate disability. Requires some help but able to walk unassisted
4 – moderately severe disability. Unable to attend to own bodily needs without assistance, and unable to walk unassisted
5 – severe disability. Requires constant nursing care and attention, bedridden, incontinent
6 - dead
Causes of SAH
Traumatic (most common)
Spontaneous - Intracranial aneurysm (berry aneurysms) Arteriovenous malformation Pituitary apoplexy Arterial dissection Mycotic aneurysms Perimesencephalic
Clinical features of SAH
Sudden onset thunderclap headache, like a baseball bat to the occipital region N+V Meningism (photophobia, neck stiffness) Coma Seizures Sudden death ECG changes may include ST elevation
Diagnosing SAH
CT head: acute blood (hyperdense/bright on CT). false negative in 7% of cases.
LP used to confirm SAH if CT is negative but there is still clinical suspicion. Performed at least 12 hours following onset of symptoms to allow for development of xanthochromia (LP findings with SAH = xanthochromia + normal or raised opening pressure)
After spontaneous SAH is confirmed, investigations for a cause:
CT intracranial angiogram (aneurysms, AVM, etc)
Digital subtraction angiogram
Management of SAH
- aneurysmal SAH management
- management of vasospasms
- management of hydrocephalus
Spontaneous SAH should be managed by treating the underlying cause.
SAH due to intracranial aneurysm: usually treated with a coil by interventional neuroradiologists, but some need a craniotomy and clipping by a neurosurgeon. Intervention should be done within 24hrs due to risk of rebleeding. Until the aneurysm is treated, patient should be kept of strict bed rest with well-controlled BP and should avoid straining.
Vasospasm is prevented using a 21 day course of nimodipine (CCB), and is treated with hypovolaemia induced-hypotension and haemodilution
Hydrocephalus is temporarily treated with an external ventricular drain (CSF diverted into a bag at the bedside) or if required, a long term ventriculo-peritoneal shunt
Complications of aneurysmal SAH
Re-bleeding Vasospasm (typically 7-14 days later) Hyponatraemia (SIADH) Seizures Hydrocephalus Death
Extradural haematoma
- what is it
- cause
- presentation
- CT
- Mx
Collection of blood between the skull and the dura
Caused by low impact trauma
- > LOC, a lucid interval, and then a rapid decline in consciousness
- > Mass effect on the brain will cause uncal herniation and a fixed dilated pupil due to CNIII compression
CT: hyperdense (bright) biconvex collection around the surface of the brain
Definitive mx: craniotomy and evacuation of the haematoma
Acute subdural haematoma
- what is it
- cause
- presentation
- CT
- Mx
Fresh collection of blood under the layer of the dura
Commonly caused by trauma but can be caused by vascular lesions
Typically caused by high speed injuries or acceleration-deceleration injuries
Varies in clinical picture from an asymptomatic patient to a severely comatose patient
CT: hyperdense (bright) crescenteric collection, not limited by suture lines, +/- midline shift
Definitive Mx: decompressive craniotomy
Chronic subdural haematoma -what is it -who does it occur in -presentation -CT Mx
Old collection of blood that is under the layer of the dura
More common in elderly, alcoholics, people on anticoag, or in infants due to fragility of bridging veins
Typically presents several weeks after a mild head injury with progressive confusion, LOC, weakness, or higher cortical dysfunction
CT: hypodense (dark) crescenteric collection around the surface of the brain that is not limited by suture lines
Mx: if symptomatic, definitive mx is burr hole drainage
Intracerebral haematoma
- what is it
- risk factors
- presentation
- CT
- Mx
Collection of blood within the substance of the brain
Risk factors: HTN, aneurysm, AV malformation, cerebral amyloid angiopathy, brain tumour, infarct
Typically presents similarly to an ischaemic stroke, or with a decrease in consciousness
CT: hyperdensity (bright) within the substance of the brain
Mx: conservative under the care of the stroke physicians, but large clots in patients with impaired consciousness may warrant surgical evacuation
Glasgow coma scale
Eyes (4): spontaneous, speech, pain, none
Verbal (5): orientated, confused conversation, inappropriate words, incomprehensible sounds, none
Motor (6): obeys commands, localises pain, normal flexion, abnormal flexion, extension, none
If GCS 8, ventilate.
Risk factors and causes of delirium
Age >65 Background of dementia Significant injury (eg. hip fracture) Frailty or multimorbidity Polypharmacy
Infection (esp UTI)
Metabolic (hypercalcaemia, hypoglycaemia, hyperglycaemia, dehydration)
Change of environment
Any significant cardiac, resp, neuro, or endocrine condition
Severe pain
Alcohol withdrawal
Constipation
Factors favouring delirium over dementia
Impairment of consciousness
Fluctuation of symptoms (worse at night, periods of normality)
Abnormal perception (illusions and hallucinations)
Agitation
Fear
Delusions
Types of delirium
Hyperactive: restlessness, mood lability, agitation, aggression
Hypoactive: slow and withdrawn
Mixed
Investigations for delirium
Look for the cause
FBC, U+E, LFT, blood glucose, ABG, septic screen (urine dip, CXR, cultures)
Consider ECG, malaria films, LP, EEG, CT
Management of delirium
Identify and treat underlying cause Reorientate patient Encourage visits from friends and family Monitor fluid balance and encourage oral intake Mobilise and encourage physical activity Practise sleep hygiene Avoid or remove catheters, IV cannulae, monitoring leads and other devices Watch out for infection and distress Review medication
Only use sedation if the patient is at risk to their own/other patient’s safety. Consider haloperidol.
Management of new dementia
Blood screen to exclude reversible causes: FBC, U+E, LFT, calcium, glucose, TFTs, vit B12 and folate
Neuroimaging to exclude other reversible conditions
Referral to an old age psychiatrist (memory clinics)
Causes of dementia
Alzheimers disease
Cerebrovascular disease
Lewy body dementia
Picks disease (frontotemporal)
Huntingtons
CJD
HIV
Important potentially treatable: Hypothyroidism Addisons B12/folate/thiamine deficiency Syphilis Brain tumour Normal pressure hydrocephalus Subdural haematoma Depression Chronic drug use
Pathological changes of Alzheimers disease
- macroscopic
- microscopic
- biochemical
- Macroscopic: widespread cerebral atrophy, particularly cortex atrophy and hippocampus atrophy
- microscopic: cortical plaques due to deposition of type A-beta-amyloid protein and intraneuronal neurofibillary tangles caused by abnormal aggregation of the tau protein
- biochemical: ACh deficit from damage to an ascending forebrain projection
Management of Alzheimers disease
Non-pharmacological: activities to promote wellbeing, group cognitive stimulation therapy, group reminiscence therapy and cognitive rehabilitation
Pharmacological:
Mild-mod: AChesterase inhibitors (donepezil, galantamine, rivastigmine)
Moderate-severe: NMDA antagonist (memantine)
Clinical features of Alzheimers disease
Memory loss
Impaired visual-spatial skill and verbal skill
Behavioural changes
Agnosia (unable to recognise self in mirror)
Lack of insight
Eventually patient becomes sedentary, taking little interest in anything
Lewy Body dementia
- pathological features
- associated disease
- features
- diagnosis
- management
Alpha-synuclein cytoplasmic inclusions (Lewy bodies) in the substantia nigra, paralimbic and neocortical areas
Associated with Parkinsons disease
Features:
Progressive cognitive impairments in attention and executive function rather than just memory loss (unlike alzheimers), cognition may be fluctuating
Parkinsonism
Visual hallucinations
Diagnosis: clinical
Single-photon emission computed tomography (SPECT) -DaTscan
Management: Achesterase inhibitors (donepezil), NMDA antagonists (memantine)
Avoid neuroleptics and the patient may develop irreversible parkinsonism
Pick’s disease
- what is it
- features
- macroscopic changes
- microscopic changes
frontotemporal dementia
Features: personality change, impaired social conduct, hyperorality, disinhibition, increased appetite, perseveration behaviours
Macroscopic changes: atrophy of the frontal and temporal lobes
Microscopic: pick bodies (aggregations of tau protein), neurofibrillary tangles, gliosis, senile plaques
Parkinsons disease features
Triad:
- Resting tremor (pill rolling)
- Hypertonia (rigidity + tremor gives cogwheel rigidity)
- Bradykinesia (slow to initiate)
Actions slow and decrease in amplitude with repetition, eg. micrographia
Festinant gait (shuffling, pitched forward, reduced arm swing)
Signs tend to be worse on one side
Expressionless face REM sleep behaviour disorder Fatigue Postural hypotension Depression
Diagnosis of parkinsons disease
Clinical diagnosis, based on symptoms and examination
The diagnosis should be made by a specialist (GP should refer to a neurology clinic)
UK Parkinsons Disease Society brain bank clinical diagnostic criteria
Parkinsons tremor vs benign essential tremor
Parkinsons: asymmetrical, 4-6 hertz, worse at rest, improves with intentional movement, other parkinsons features present, no change with alcohol
Benign essential tremor: symmetrical, 5-8Hz, improves at rest, worse with intentional movement, no other parkinsons features, improves with alcohol
Management of Parkinsons disease
First-line if motor symptoms are affecting a patient’s QoL: levodopa and decarboxylase inhibitor (=co-careldopa)
First line if motor symptoms are not affecting QoL: non-ergot derived dopamine agonist, co-careldopa, or MAO-B inhibitor
If patient is on co-careldopa and has symptoms despite max treatment or starts developing dyskinesia, then add a dopamine agonist, MAO-B inhibitor or COMT inhibitor as an adjunct
Parkinson’s patients must always have their medication on time due to the risk of acute akinesia or neuroleptic malignancy syndrome if medication is not taken/absorbed
Management of postural hypotension in parkinsons patients
Medication review first
If symptoms persist then midodrine can be considered (increases peripheral arterial resistance by acting on alpha adrenergic receptors)
Levodopa
- which medication should it be combined with and why
- complications
- side effects
Combined with decarboxylase inhibitor (=co-careldopa) to prevent peripheral metabolism of levodopa into dopamine
Reduced effectiveness with time (approx 2 years)
SEs: dyskinesia, on-off effect, dry mouth, anorexia, palpitations, postural hypotension, psychosis, drowsiness
Don’t stop medication suddenly. Dopamine agonist patch should be given if drugs cant be taken orally, to prevent acute dystonia
Dopamine agonists
- ergot derived dopamine agonist side effects and monitoring requirements
- side effects of dopamine agonists
Ergot-Derived: bromocriptine, cabergoline. Associated with pulmonary, retroperitoneal and cardiac fibrosis. Echo, ESR, creatinine and CXR should be done before treatment and patients should be closely monitored
Non-ergot derive (ropinirole)
Dopamine agonists may cause impulse control disorders and excessive daytime somnolence
More likely to cause hallucinations than levodopa. Nasal congestion and postural hypotension also seen in some patients
Monoamine-oxidase B inhibitors
-MoA
Eg. Selegiline
Inhibits breakdown of dopamine secreted by dopaminergic neurones
Not useful in later disease when dopaminergic neurones stop secreting dopamine
SEs: postural hypotension, AF
Amantadine
Mechanism not fully understood, but may increase dopamine release and inhibit its uptake at dopaminergic synapses
SEs: ataxia, slurred speech, confusion, dizziness, livedo reticularis
Sleep disorders and parkinsons
+management
Parkinsons patients may experience restless leg syndrome and REM sleep behaviour disorder
Consider clonazepam or melatonin to treat this
Non-pharmacological management of parkinsons disease
Physiotherapy referral
Occupational therapy
SALT for patients who are experiencing problems with communication, swallowing or saliva
Dietitian input
Parkinson’s-plus syndromes
Multiple System Atrophy: early autonomic features (impotence, incontinence), postural hypotension, cerebellar and pyramidal signs, rigidity > tremor
Lewy Body dementia
Progressive supranuclear palsy: early postural instability, vertical gaze palsy, falls, rigidity of trunk > limbs, symmetrical symptoms, speech and swallow problems, little tremor
Corticobasal degeneration: akinetic rigidity involving one limb, cortical sensory loss, apraxia (alien limb phenomenon)
Secondary causes of parkinsonism
Vascular parkinsonism: diabetic/hypertensive patients with postural instability and falls
Drug-induced (antipsychotics, metoclopramide)
Wilsons disease
Post-encephalitis
Dementia pugilistica (secondary to chronic head trauma)
Toxins (carbon monoxide)
Neurosyphilis
Differential diagnoses of a tremor
Parkinsons disease Benign essential tremor Anxiety CO2 retention Cerebellar disease Drug withdrawal MS Huntingtons Chorea Hyperthyroidism Fever Medications (eg. antipsychotics)
Neuroleptic malignant syndrome
- cause
- pathophysiology
- features
- ix
- mx
Rare but dangerous condition seen in patients who take anti-dopaminergic antipsychotics or parkinsons patients who stop their drugs suddenly
Pathophysiology: dopamine blockade triggers a massive release of glutamate and subsequent neurotoxicity and muscle damage
Occurs within hours to days of starting an antipsychotic or stopping parkinsons meds
-> pyrexia, muscle rigidity, autonomic lability (HTN, tachycardia, tachypnoea), agitated delirium with confusion
Ix: raised creatine kinase, AKI, leukocytosis
Mx: stop antipsychotic, transfer to a medical ward or ICU, IV fluids prevent renal failure, dantrolene may be required in selective cases, bromocriptine or other dopamine agonists may be needed
Multiple sclerosis
- what is it/ pathophysiology
- epidemiology
- subtypes
Chronic, progressive condition that involves demyelination of the myelinated neurones in the CNS (oligodendrocytes), caused by an inflammatory process involving activation of immune cells against the myelin.
The inflammatory plaques are disseminated in space and time (occur at multiple sites with >30days between attacks)
Typically presents in young adults (20-40) and more common in women
Relapsing-remitting: most common. Acute attacks followed by periods of remission.
Secondary progressive: relapsing-remitting patients who have deteriorated and have developed neurological signs and symptoms between relapses, usually within 15 years of diagnosis. gait and bladder disorders are usually seen.
Primary progressive: progressive deterioration from onset. More common in older people.
MS diagnosis
Diagnosed by a neurologist.
McDonald Criteria.
Diagnosis can be made on the basis of two or more relapses and either objective clinical evidence of two or more lesions, or objective clinical evidence of one lesion together with historical evidence of a previous relapse
Symptoms have to be progressive over a period of one year to diagnose primary progressive MS
Investigations:
MRI to demonstrate typical lesions, disseminated in time and space
Lumbar puncture can detect oligoclonal bands of IgG in the CSF which arent present in the serum (= CNS inflammation)
Evoked potentials - delayed visual, auditory and somatosensory
Alternative diagnoses should be excluded
MS features
Visual: optic neuritis (common presenting features), optic atrophy, Uhthoff’s phenomenon (worsening vision following a rise in body temp, eg after bath), internuclear ophthalmoplegia
Sensory: pins and needles, numbness, trigeminal neuralgia, Lhermittes syndrome (paraesthesiae in limbs on neck flexion)
Motor: UMN/spastic weakness (commonly in legs)
Cerebellar: ataxia, tremor
Others: urinary incontinence, sexual dysfunction, intellectual deterioration, fatigue
Lhermittes sign
Paraesthesia down the spine and into the limbs when flexing the neck.
Indicates disease in the cervical spinal cord in the dorsal column.
Caused by stretching the demyelinated dorsal column
Uhthoff’s phenomenon
Worsening of symptoms, and worsening of vision when there is a rise in body temperature (eg. after a bath)
Management of MS
Specialist MDT: neurologists, specialist nurses, physiotherapy, OT
Disease modifying drugs and biologic therapies can induce long term remission
Methylprednisolone during a relapse can shorten a relapse
Symptom control:
- Spasticity: baclofen or gabapentin
- Trigeminal neuralgia: carbamazepine
- Tremor: botulinum toxin
- Urgency/frequency: intermittent self catheterisation, or tolterodine
- Fatigue: amantadine, CBT, exercise
Types of motor neurone disease
Amyotrophic lateral sclerosis (most common): LMN signs in arms and UMN signs in legs
Primary lateral sclerosis: UMN signs only
Progressive muscular atrophy: LMN signs only, affects distal muscles before proximal, carries best prognosis
Progressive bulbar palsy: palsy of the tongue, muscles of chewing/swallowing, and facial muscles due to loss of function of brainstem motor nuclei, carries worst prognosis
Motor neuron disease
- cause
- features
- diagnosis
Unknown cause
Rare before 40y
Features which point towards MND:
- Mixture of LMN and UMN signs
- Fasciculations
- Absence of sensory signs
- Wasting of small hand muscles/tibialis anterior
Doesnt affect external ocular muscles, no cerebellar signs, abdominal reflexes are usually preserved and sphincter dysfunction is a late feature
Diagnosis:
Clinical diagnosis
Nerve conduction studies will show normal motor conduction and can help exclude neuropathy
Electromyography shows reduced number of action potentials with increased amplitude
MRI excludes cervical cord compression and myelopathy
Management of MND
Riluzole: glutamate inhibitor, used mainly in ALS, prolongs life by about 3 months
Respiratory care: NIV (BIPAP) at night, prolongs life by about 7 months
Palliative input
Prognosis: poor. 50% die within 3 years.
Cervical spondylosis
- pathophysiology
- features
- management
Degeneration of the annulus fibrosus of the cervical spine and osteophyte formation fo the adjacent vertebrae -> narrowing of spinal canal and intervertebral foramina
Features: Neck stiffness Crepitus on moving neck Stabbing or dull arm pain Forearm/wrist pain Root compression (radiculopathy) Cord compression
Mx:
If red flags: Urgent MRI and specialist referral
Analgesia (WHO pain ladder)
Encourage gentle activity
If no improvement in 4-6 weeks, then MRI and consider neurosurgical referral for injections or surgical decompression
Cervical radiculopathy
- what is it
- features
Cervical spinal root compression due to cervical spondylosis
->
Pain/electrical sensations in arms or fingers at the level of the compression, numbness, dull reflexes, LMN weakness, and eventual wasting of muscles innervated by affected root
Cord compression as a result of cervical spondylosis
UMN signs below the level of the affected root, and LMN signs at the level of the affected root.
weakness, clumsy hands, gait disturbance
UMN leg signs (spastic weakness, upgoing plantars)
LMN arm signs (wasting, hyporeflexia)
Incontinence, hesitancy, urgency
Clinical patterns of nerve root impingement:
C5 (C4/5 disc)
Weak deltoid and supraspinatus
Reduced supinator jerks
Numb elbow
Pain in neck/shoulder that radiates down front of arm to elbow
Clinical patterns of nerve root impingement:
C6 (C5/6 disc)
Weak biceps and brachioradialis
Reduced bicep jerk
Numb thumb and index finger
Pain in shoulder radiating down arm below elbow
Clinical patterns of nerve root impingement:
C7 (C6/7 disc)
Weak triceps and finger extension
Reduced triceps jerk, numb middle finger
Pain in upper arm and dorsal forearm
Clinical patterns of nerve root impingement:
C8 (C7/T1 disc)
Weak finger flexors and small muscles of the hand
Numb 5th and ring finger
Pain in upper arm and medial forearm
Causes of myopathies
Inflammatory: polymyositis
Inherited: duchenne/becker muscular dystrophy, myotonic dystrophy
Endocrine: Cushing’s, thyrotoxicosis
Alcohol
Duchenne muscular dystrophy
- cause
- mutation
- features
X-linked recessive mutation in the gene encoding dystrophin
Frameshift mutation resulting in one or both of the binding sites being lost, leading to a severe form
Progressive proximal muscle weakness from 5 years
Calf pseudohypertrophy
Gower’s sign: child uses arms to stand up from a squatted position
30% have intellectual impairment
Becker muscular dystrophy
- cause
- mutation
- features
X-linked recessive mutation in the gene encoding dystrophin
Non-frameshift insertion in the dystrophin gene resulting in both binding sites being preserved leading to a milder form
Similar features to duchennes but milder form
Proximal muscle weakness from 10 years
Intellectual impairment less common
Investigations for myopathies
ESR, CK, AST, LDH - all raised
Electromyography
Tests relevant to systemic causes (eg. TFTs)
Muscle biopsy and genetic testing
Pathway of the facial nerve
The facial nerve exits the brainstem at the cerebellopontine angle. It passes through the temporal bone and parotid gland where it terminates into its 5 branches:
temporal, zygomatic, buccal, marginal mandibular, cervical
functions of the facial nerve
Motor: facial expression, stapedius in the inner ear, some muscles in the neck
Sensory: taste from the anterior 2/3 of the tongue
Parasympathetic: submandibular and sublingual salivary glands, and the lacrimal gland
UMN vs LMN facial nerve palsy
Each side of the forehead has UMN innervation by both sides of the brain
Each side of the forehead has LMN innervation from one side of the brain.
UMN lesions (stroke) -> forehead will be spared and the patient can move their forehead on the affected side.
LMN lesions (bells palsy) -> forehead will not be spare and the patient cannot move their forehead on the affected side
Bells palsy
- cause
- incidence
- features
- mx
- prognosis
Idiopathic
Unilateral LMN facial nerve palsy
Peak incidence 20-40yrs, more common in pregnant women
Features: unilateral facial weakness, forehead affected, post-auricular pain, altered taste, dry eyes, hyperacusis
If patients present within 72 hours of symptoms, consider prednisolone
Patients also require lubricating eye drops and tape eye closed at night
Prognosis: majority recover over several weeks, but may take up to 12 months. Some are left with residual weakness
Causes of unilateral facial nerve palsies
UMN: stroke
LMN: bell’s palsy, Ramsay-Hunt, acoustic neuroma, parotid tumours, HI, MS, DM
Causes of bilateral facial nerve palsy
Sarcoidosis, Guillain-Barre syndrome, Lyme disease, bilateral acoustic neuromas (neurofibromatosis type 2)
Ramsay-Hunt syndrome
Caused by Herpes-Zoster virus
Unilateral facial nerve palsy
Painful and tender vesicular rash in the ear canal, pinna and around the ear on the affected side
Rash can extend to the anterior two thirds of the tongue and hard palate
Treatment should be initiated within 72 hours: prednisolone and aciclovir
+lubricating eye drops
Signs caused by space-occupying lesions
Raised ICP: headache worse on waking, lying down, bending forward or coughing. vomiting, papilloedema, reduced GCS
Seizures
Evolving focal neurology
Subtle personality change (irritability, lack of initiative, socially inappropriate)
Localising focal neurological features to a space-occupying lesion
Temporal lobe: dysphasia, contralateral homonymous hemianopia, amnesia
Frontal: hemiparesis, personality change, grasp reflex, brocas dysphasia, unilateral anosmia, perseveration, executive dysfunction, reduced verbal fluency
Parietal: hemisensory loss, reduced two point discrimination, unable to recognise an object by touch alone, sensory inattention, dysphasia
Occipital: contralateral visual field defects, persisting images once the stimulus has left the field of view (palinopsia), polyopsia (seeing multiple images)
Cerebellum (DANISH): dysdiadochokinesia, ataxia, nystagmus, intention tremor, slurred speech, hypotonia
Causes of space-occupying lesions in the brain
Primary tumour: astrocytoma, glioblastoma, oligodendroglioma, meningioma, primary CNS lymphoma Brain mets: breast, lung, melanoma Aneurysm Abscess Chronic subdural haematoma Granuloma Cyst
Tumour management
Benign: surgical excision if possible
Malignant: hard to resect, but excise if possible. Debulking radiotherapy pre-op. Chemo-radiotherapy post-op
Seizure prophylaxis
Treat any headache with analgesia
Treat cerebral oedema with dexamethasone (mannitol if acute rise in ICP)
Acoustic neuroma/ vestibular schwannoma
- what is it
- features
- associated condition
- Ix
Tumour of the schwann cells surrounding the auditory nerve of CNVIII
They occur around the cerebellopontine angle and may compress other nerves (CNV, CNVII)
Features: vertigo, hearing loss, tinnitus and an absent corneal reflex, facial nerve palsy
Bilateral acoustic neuromas are seen in neurofibromatosis type 2
-Ix: MRI of the cerebellopontine angle
Wernicke’s aphasia
Receptive aphasia, due to a lesion of the superior temporal gyrus. typically supplied by the inferior division of the left MCA
Lesions result in sentences that make no sense, word substitution and neologisms but speech remains fluent.
Comprehension is impaired
Broca’s aphasia
Expressive aphasia. Due to a lesion of the inferior frontal gyrus. Typically supplied by the superior division of the left MCA.
Speech is non-fluent, laboured, and halting.
Comprehension is normal
Conduction aphasia
Classically due to a stroke affecting the arcuate fasciculus (connects wernickes and brocas)
Speech is fluent but repetition is poor
Aware of errors they are making
Comprehension is normal
Different types of ataxia caused by lesions to different areas of the cerebellum
Cerebellar hemisphere lesions cause peripheral ataxia (finger-nose ataxia)
Cerebellar vermis lesions cause gait ataxia
Contents of the cavernous sinus
Contents of the sinus: internal carotid artery, abducens nerve
Lateral wall components: CNIII, CNIV, CNV1, CNV2
Causes of cerebellar syndrome
Friedreich’s ataxia, ataxia telangiectasia, neoplastic (cerebellar haemangioma), stroke, alcohol, multiple sclerosus, hypothyroidism, drugs (phenytoin, lead poisoning), paraneoplastic (secondary to lung cancer)
Cerebral perfusion pressure
Mean arterial pressure - intracranial pressure = cerebral perfusion pressure
the net pressure gradient causing blood flow to the brain. Tightly autoregulated.
A sharp rise in CPP can cause raised ICP, and a fall in CPP can cause ischaemia
Circulation of CSF
Produced by the ependymal cells in the choroid plexus or in the blood vessels. It travels to the lateral ventricles via the foramen of munro, then to the third ventricle, then through the cerebral aqueduct into the 4th ventricle, and then into the subarachnoid space, where it is reabsorbed into the venous system via arachnoid granulations into superior sagittal sinus
Vol of CSF in the brain
Vol of CSF produced
150ml in the brain
500ml produced by ependymal cells in the choroid plexus or blood vessels
Charcot-Marie-Tooth disease
- what is it
- features
- management
most common inherited peripheral neuropathy
Predominantly motor loss
features: sprained ankles, foot drop, high arched feet, hammer toes, distal muscle weakness, distal muscle atrophy, hyporeflexia, stork leg deformity
No cure, management is focused on physical and occupational therapy
Common peroneal nerve lesion
Occurs at the neck of the fibula
Features: foot drop, week dorsiflexion, weak foot eversion, weakness of extensor hallucis longus, sensory loss over dorsum of foot and lower lateral part of leg, wasting of the anterior tibial and peroneal muscles
Cranial nerve reflexes afferent and efferent limbs
- Corneal
- Jaw jerk
- Gag
- Carotid sinus
- Pupillary light
- Lacrimation
- Corneal: ophthalmic nerve (V1), facial nerve (VII)
- Jaw jerk: mandibular (V3), mandibular (V3)
- Gag: glossopharyngeal (IX), vagal (X)
- Carotid sinus: glossopharyngeal (IX), vagal (X)
- Pupillary light: optic (II), oculomotor (III)
- Lacrimation: ophthalmic (V1), facial (VII)
Creutzfeldt-Jakob disease
- what happens
- features
- different types
- investigations
- Rapidly progressive neurological condition caused by prion proteins, which induce formation of amyloid folds resulting in tightly packed beta-pleated sheets resistant to proteases
- Features: rapid onset dementia, myoclonus
- Sporadic: 85% of cases, some are familial, mean age of onset 65
- New variant: average onset 25, median survival 13 months. Psychological symptoms (anxiety, withdrawal, dysphonia)
-Ix: CSF is usually normal, EEG (biphasic, high amplitude sharp waves in sporadic CJD), MRI (hyperintense signals in the basal ganglia and thalamus)
Encephalitis
- pathophysiology
- features
- ix
- mx
-HSV-1 responsible for most adult cases, typically affects temporal and inferior frontal lobes
-Features: fever, headache, psychiatric symptoms, seizures, vomiting, focal features
Peripheral lesions have no relation to presence of HSV encephalitis
- Ix:
- CSF: lymphocytosis, elevated protein
- PCR for HSV
- CT: medial temporal and inferior frontal changes
- MRI is better than CT
- EEG: lateralised periodic discharges at 2 Hz
-Mx: IV aciclovir
Friedreich’s ataxia vs ataxia telangiectasia
Friedreichs: autosomal recessive, cerebellar ataxia, onset 10-15yrs, kyphoscoliosis, HOCM, DM, optic atrophy
Ataxia telangiectasia: autosomal recessive, cerebellar ataxia, onset 1-5 years, increased risk of lymphoma and leukaemia, IgA deficiency (infections), telangiectasia
Guillain-Barre syndrome
- what is it
- pathophysiology
Immune mediated demyelination of peripheral nervous system, often triggered by infection
Pathophysiology: cross reaction of antibodies with gangliosides in the peripheral nervous system. Correlation between anti-ganglioside antibodies (anti-GM1) and clinical features has been demonstrated
Associated with campylobacter jejuni, cytomegalovirus and Epstein-Barr virus
Guillain-barre syndrome features
Progressive weakness of all four limbs Classically ascending (lower extremities affected first), but proximal affected earlier than distal
Sensory symptoms tend to be mild
Other features: history of gastroenteritis, areflexia, cranial nerve involvement, autonomic involvement (urinary retention, diarrhoea)
Less common features: papilloedema
Investigations for guillain-barre syndrome
Lumbar puncture: rise in protein with a normal WCC
Nerve conduction studies
Management and prognosis of Guillain-Barre
Mx: IV immunoglobulins, plasma exchange, supportive care, VTE prophylaxis (PE common), intubation and ventilation due to resp failure
Prognosis: symptoms usually start within 4 weeks of preceding infection. Symptoms peak within 2-4 weeks and then there is a recovery period that can last months-years
Huntington’s disease
- cause/pathophysiology
- prognosis
Inherited neurodegenerative condition
Progressive and incurable
Typically results in death 20 years after onset of symptoms
Autosomal dominant
Degeneration of cholinergic and GABAergic neurons in the striatum of the basal ganglia
Features of Huntington’s
Chorea Personality changes (irritability, apathy, depression) Intellectual impairment Dystonia Saccadic eye movements Speech difficulties Swallowing difficulties
Genetic anticipation: successive generations have more repeats in the gene, resulting in earlier age of onset and increased severity of disease
Idiopathic intracranial hypertension
- risk factors
- features
- management
- Risk factors: young overweight females, pregnancy, drugs (OCP, steroids, tetracycline, vit A, lithium)
- Features: headache, blurred vision, papilloedema, enlarged blind spot, CNVI palsy
- Mx: weight loss, diuretics (acetazolamide), topiramate, repeated LP, optic nerve sheath decompression and fenestration, lumboperitoneal or ventriculoperitoneal shunt
Meralgia paraesthetica
Mononeuropathy
Lateral cutaneous nerve of the thigh (L2-L3)
Anterolateral burning thigh pain from entrapment under the inguinal ligament
Internuclear ophthalmoplegia
Impaired adduction of the ipsilateral eye with horizontal nystagmus of the abducting eye on the contralateral side
Due to a lesion in the medial longitudinal fasciculus, which connects the cranial nuclei of CNIII, CNIV, and CNVI
Seen in MS and vascular disease
Cavernous sinus thrombosis
Periorbital oedema
Ophthalmoplegia
Trigeminal nerve involvement
Central retinal vein thrombosis
Lambert-Eaton syndrome
- associated condition
- cause
- features
- EMG features
- Mx
Associated with small cell lung cancer
Antibodies directed against presynaptic voltage-gated calcium channels in the peripheral nervous system
Features: repeated muscle contractions lead to increased muscle strength (opposite of MG), limb-girdle weakness, hyporeflexia, autonomic symptoms
EMG: incremental response to repetitive electrical stimulation
Mx: treat underlying cancer, immunosuppression with prednisolone or azathioprine, IV Ig and plasma exchange may be beneficial
Meningitis
- common causes in adults
- symptoms
- signs
- neurological sequelae
- Meningococcus, pneumococcus
- Symptoms: headache, fever, N+V, photophobia, drowsiness, seizures
- Signs: neck stiffness, purpuric rash
- Neurological sequelae: sensorineural hearing loss, epilepsy, paralysis, intracerebral abscess, sepsis, brain herniation, hydrocephalus
CSF findings in meningitis
- bacterial: appearance, glucose, protein, WCC
- viral: appearance, glucose, protein, WCC
- TB: appearance, glucose, protein, WCC
- bacterial: appearance cloudy, glucose low (1/2 of plasma), protein high, WCC high
- viral: appearance clear/cloudy, glucose 60-80% of plasma, protein normal/raised, WCC high but less high than bacterial
- TB: appearance slightly cloudy/ fibrin web, glucose low (1/2 of plasma), protein high, WCC not as high as bacterial
Management of meningitis
Pre-hospital antibiotics before transfer: IM benzylpenicillin
Empirical therapy <3m: IV cefotaxime and amoxicillin
Empirical therapy 3m-50y: IV cefotaxime
Empirical therapy >50: IV cefotaxime and amoxicillin
Meningococcal meningitis: IV benzylpenicillin of cefotaxime
Pneumococcal meningitis: IV cefotaxime
H influenze meningitis: IV cefotaxime
Listeria meningitis: IV amoxicillin + gentamicin
Dexamethasone IV should be given to reduce risk of neuro sequelae
Prophylaxis should be given to contacts
Investigations for meningitis
FBC CRP Coagulation screen Blood culture Whole-blood PCR Blood glucose Blood gas
Lumbar puncture if no signs of raised ICP
Myaesthenia gravis
- what is it
- associated conditions
Autoimmune antibodies against acetylcholine receptors
Associated conditions: thymomas, thymic hyperplasia, autoimmune (pernicious anaemia, autoimmune thyroid disorder, RA, SLE)
Features of myaesthenia gravis
Fatiguability (muscles become progressively weaker during periods of activity)
Extraocular muscle weakness (diplopia)
Proximal muscle weakness (face, neck, limb girdle)
Ptosis
Dysphagia
Investigations for myaesthenia gravis
Single fibre electromyography (high sensitivity)
CT thorax to exclude thymoma
Creatine kinase is normal
Autoantibodies (antibodies to ACh receptors, or anti-muscle-specific tyrosine kinase antibodies)
Tensilon test: IV endrophonium reduces muscle weakness temporarily
Management of myaesthenia gravis
Long acting acetylcholinesterase inhibitors (pyridostigmine)
Immunosuppression (prednisolone)
Thymectomy
Myaesthenic crisis
- what is it
- management
Life-threatening weakness of respiratory muscles during a relapse.
Mx: Plasmapharesis, IV immunoglobulins, may require ventilatory support
Side effects of myaesthenia gravis treatment
Pyridostigmine is an acetylcholinesterase inhibitor.
Gives cholinergic side effects: incresaed salivation, lacrimation, swaets, vomiting, miosis
May have a cholinergic crisis
Exacerbating factors of myaesthenia gravis
Exertion Pregnancy Hypokalaemia Infection Change of climate Emotion Drugs: penicillamine, quinidine, procainamide, beta blockers, lithium, phenytoin, antibiotics (gentamicin, macrolides, quinolones, tetracyclines)
Neurofibromatoses
- inheritance
- type 1 features
- type 2 features
Both autosomal dominant
Type 1: cafe-au-lait spots (>6, 15mm diam), axillary/ groin freckles, peripheral neurofibromas, iris haematoma, scoliosis, phaeochromocytoma
Type 2: bilateral acoustic neuromas, multiple intracranial schwannomas, meningiomas, and ependymoma
Normal pressure hydrocephalus
- what is it and what is it caused by
- triad of symptoms
- investigations
- management
Reversible cause of dementia
Secondary to reduced CSG absorption at the arachnoid villi
May be secondary to head injury, SAH or meningitis
Triad: urinary incontinence, dementia, gait abnormality (wet, wacky and wobbly)
Investigations: CT head or MRI head will show hydrocephalus with an enlarged fourth ventricle
management: ventriculoperitoneal shunting
Peripheral neuropathies which predominantly cause motor loss
Guillain-Barre syndrome
Porphyria
Lead poisoning
Hereditary sensorimotor neuropathies (Charcot-Marie-Tooth)
Chronic inflammatory demyelinating polyneuropathy
Diphtheria
Peripheral neuropathies which predominantly cause sensory loss
Diabetes, uraemia, leprosy, alcoholism, vit B12 deficiency, amyloidosis
Features of post-lumbar puncture headache
Typically occurs in young females with a low BMI
Usually develops 24-48 hours following an LP but may occur a week later
May last several days
Worsens with upright position
Improves with recumbent position
Management of post-lumbar puncture headache
Supportive (analgesia, rest)
If pain continues for >72 hours then a specific treatment is indicated in order to prevent subdural haematoma
Treatment option: blood patch, epidural saline, IV caffeine
Which roots are tested during the following reflexes -
- ankle
- knee
- biceps
- triceps
- ankle: S1-S2
- knee: L3-L4
- biceps: C5-C6
- triceps: C7-C8
Brown-Sequard syndrome
- Cause
- Tracts affected
- Clinical features
- Spinal cord hemisection
- Tracts affected: lateral corticospinal tract, dorsal columns, lateral spinothalamic tract
-Features:
=Ipsilateral spastic paralysis below the lesion (UMN lesion affecting corticospinal tract)
=Ipsilateral loss of proprioception and vibration sensation (DCML tract)
=Contralateral loss of pain and temperature sensation (lateral spinothalamic tract)
Subacute combined degeneration of the spinal cord
- cause
- tracts affected
- clinical features
- complication if not treated
- Which other condition has these same features (in addition to cerebellar ataxia/DANISH)
- Vitamin B12 deficiency
- Tracts affected: the dorsal and lateral columns -> lateral corticospinal tracts, spinocerebellar tracts, dorsal column medial lemniscus
-Features:
=Bilateral spastic paralysis (corticospinal tracts)
=Bilateral loss of proprioception and vibration sensation (DCML)
=Bilateral limb ataxia (spinocerebellar)
Joint position and vibration sense is lost first and then distal paraesthesia
UMN signs in the legs: extensor plantars, brisk knee reflexes, absent ankle jerks
If untreated, stiffness and weakness persists
-Friedreich’s ataxia also presents in this way, with the addition of cerebellar ataxia (DANISH)
Anterior spinal artery occlusion
- spinal tracts affected
- clinical features
-Tracts affected: lateral corticospinal tracts, lateral spinothalamic tracts
-Features:
=Bilateral spastic paralysis (corticospinal)
=Bilateral loss of pain and temperature sensation (spinothalamic)
Syringomyelia
- what is it
- what is syringobulbia
- causes
- typical presentation
- what causes the presentation
- other features
- investigations
- management
Collection of CSF within the spinal cord
Syringobulbia is a fluid-filled cavity within the medulla of the brainstem. Often an extension of the syringomyelia.
Causes: chiari malformation (strong association), trauma, tumours, idiopathic
Presentation: cape-like (neck and arms) distribution of loss of sensation to pain and temperature (lateral spinothalamic), but preservation of light touch, proprioception and vibration (DCML)
Due to the crossing of the spinothalamic tracts in the anterior commissure of the spinal cord being the first tracts to be affected
Other features: spastic weakness (mostly upper limbs), paraesthesia, neuropathic pain, upgoing plantars, bowel and bladder dysfunction
Scoliosis will occur over a matter of years if untreated
Ix: full spine MRI with contrast to exclude tumour or tethered cord
Brain MRI to exclude chiari malformation
Mx: treat the cause of the syrinx. If syrinx is persistent or symptomatic, a shunt can be placed into the syrinx
Trigeminal neuralgia
- what is it
- features
- causes/ associated conditions
- management
Unilateral electric shock-like pains, abrupt in onset and termination, limited to one of more divisions of the trigeminal nerve
Often evoked by light touch, including brushing teeth and talking
Frequently occurs spontaneously
Idiopthic, compression of trigeminal roots by tumours/ vascular problems, multiple sclerosus
Management: carbamazepine is first line
Trigeminal neuralgia red flags suggesting a serious underlying cause
Sensory changes
Deafness and other ear problems
History of skin or oral lesions that could spread perineurally
Pain only in the ophthalmic division of the trigeminal nerve, or bilaterally
Optic neuritis
Family history of multiple sclerosis
Age of onset before 40 years
Tuberous sclerosus
- inheritance
- cutaneous features
- neurological features
- other features
- Autosomal dominant
- Cutaneous features: ash-leaf spots, roughened patches of skin over lumbar spine, angiofibromas over the nose, fibromata beneath the nail, cafe-au-lait spots
- Neuro: developmental delay, epilepsy, intellectual impairment
- Others: retinal hamartomas, gliomatous changes in the brain lesions, polycystic kidneys, lung cysts, heart lesions
Wernicke’s encephalopathy
- causes
- triad of features
- other features
- investigations
- management
- complication
- Causes: thiamine deficiency (alcoholics most commonly, or persistent vomiting, stomach cancer, dietary deficiency)
- Triad: ophthalmoplegia/ nystagmus, ataxia, confusion
- Other features: peripheral sensory neuropathy, altered GCS, petechial haemorrhages in the brain
- Ix: MRI, decreased red cell transketolase
- Mx: urgent replacement of thiamine
- Complication: Korsakoff syndrome
Korsakoff syndrome
Occurs if Wernicke’s encephalopathy is not treated with thiamine urgently
Korsakoff syndrome = Wernicke’s triad (ophthalmoplegia/ nystagmus, ataxia, confusion) + antero-retrograde amnesia and confabulation
What is coning?
Herniation of the cerebral tonsils through the foramen magnum, resulting in compression of the brainstem. Occurs when there is a rise in ICP and shifts in CSF
Grave sign and usually indicates a neurosurgical emergency requiring intervention
Can cause Cushings reflex if not treated (hypertension, bradycardia, altered respiration)
Types of brain herniations
- subfalcine
- central
- transtentorial/ uncal
- tonsillar
- transcalvarial
- Subfalcine: displacement of cingulate gyrus under the falx cerebri
- Central: downward displacement of the brain
- Transtentorial/ uncal: displacement of the uncus of the temporal lobe under the tentorium cerebelli -> ipsilateral fixed dilated pupil due to parasympathetic compression of CNIII, and contralateral paralysis due to compression of the cerebral peduncle
- Tonsillar: displacement of the cerebellar tonsils through the foramen magnum (coning). In raised ICP this causes compression of the brainstem (cardioresp centre), will lead to cushings reflex
- Transcalvarial: occurs when brain is displaced through a defect in the skull
Why do you get Cushing’s reflex symptoms?
HTN: the brain autoregulates its own blood supply. As ICP rises, the systemic circulation will change in order to meet the perfusion needs of the brain, resulting in HTN.
Bradycardia and altered respiration: As ICP rises further, the brainstem will be compressed which is where the cardiorespiratory centre is located.
Two types of hydrocephalus and their causes
Obstructive (non-communicating) and non-obstructive (communicating)
Obstructive: due to a structural pathology blocking the flow of CSF -> leads to dilation of the ventricular system proximal to the site of obstruction
Causes: tumour, acute haemorrhage, developmental abnormalities
Non-obstructive: due to an imbalance of CSF production and absorption. Either caused by increased production (choroid plexus tumour) or reduced absorption (meningitis, post-haemorrhagic)
Hydrocephalus investigations
CT head is first line
MRI may be used to investigate in more detail
Lumbar puncture is diagnostic and therapeutic
Lumbar puncture must not be used in obstructive hydrocephalus since the difference of cranial and spinal pressure induced by the drainage of CSF will cause brain herniation
Management of hydrocephalus
External ventricular drain is used in acute, severe hydrocephalus (typically inserted into the right lateral ventricle and drains into a bag at the bedside)
Ventriculoperitoneal shunt is a long term CSF diversion that drains CSF from the ventricles to the peritoneum
If obstructive, the treatment may involve surgical removal of the obstruction
Clinical features of hydrocephalus
- in adults
- in infants
Symptoms due to raised ICP Headache (worse in the morning, when lying down and during valsalva) N+V Papilloedema Coma
Infants may have an increased head circumference as their sutures have not fused, they will also have a bulging anterior fontanelle. Children with severe hydrocephalus may have sunsetting eyes (failure of upward gaze) due to compression of the superior colliculus of the midbrain
Causes of cerebellar dysfunction
Tumours MS Vascular – haemorrhagic or ischaemic Infections – abscess, prion disease, viral encephalitis Toxins – anticonvulsants, alcohol Metabolic- myxoedema, vitamin deficiency Trauma Multiple system atrophy Developmental deformities Inherited cerebellar ataxia
Gait disorders
- Hemiplegic
- Diplegic
- Festinant
- Ataxic
- Neuropathic
- Antalgic
- Trendelenburg
- Hemiplegic: spastic lower limb is held out in extension, so move by abduction and circumduction
- Diplegic: same as hemiplegic but bilateral. Scissoring gait
- Festinant: parkinsonian. Stooped forward, shuffling, slow to initiate and then gets quicker, slow to turn around, reduced arm swing on one side
- Ataxic: broad-based, staggers, looks drunk
- Neuropathic: common peroneal nerve damage causes footdrop and a high steppage gait to clear the toes off the ground
- Antalgic: painful, reduced stance phase on affected limb
- Trendelenburg gait: weakness in proximal muscles of lower limb girdle, weak gluteal muscles cannot stabilise the weight-bearing hip, causing the opposite hip and trunk to droop towards the leg in swing phase
Cauda equina
- causes
- presentation
- investigations
- management
- complications
- Causes: herniation of lumbar disc most common at L4/L5 and L5/S1, tumours, truama, infection, congenital (spina bifida)
- Presentation: lower back pain, urinary incontinence/retention, reduced sensation in perianal area, decreased anal tone, lower limb motor weakness and sensory deficit
- Ix: clinical diagnosis. MRI spine
- Mx: immobilise spine, surgical removal or blood/fragments/tumour/etc, lesion debulking for space occupying lesion, radiotherapy if surgery not appropriate
- Complications: paralysis, sensory abnormalities, bladder/bowel/sexual dysfunction
Decussation of the corticospinal tracts
Descending motor tract
Decussates at the lower medulla
Lesion above the medulla = contralateral weakness
Lesion below the medulla = ipsilateral weakness
Decussation of the DCML
Ascending sensory tract for proprioception, two point discrimination, light touch, vibration
Decussates at the gracile and cuneate nuclei in the medulla
Sacral fibres are more medial and cervical fibres are more lateral
Decussation of spinothalamic tract
Ascending sensory tract for pain and temperature
Decussates one or two spinal levels higher
Sacral fibres are more lateral and cervical fibres are more medial
