Neurology Flashcards
Define Parkinson’s Disease
A chronic progressive neurodegenerative disorder of the dopaminergic neurones of the substantia nigra characterised by cardinal symptoms of bradykinesia, resting tremor, rigidity and postural instability.
Explain the risk factors of Parkinson’s Disease
Increasing age
Family history of young-onset Parkinson’s
Genetics
MPTP exposure
Chronic exposure to metals causes Parkinsonism syndrome
Male sex
Head trauma
Toxin exposure
Explain the aetiology of Parkinson’s disease
Sporadic/Idiopathic Parkinson’s Disease:
Most common
Unknown aetiology
Genetic predisposition with subsequent environment factors/exposures
May be related to environmental toxins and oxidative stress
Secondary Parkinson’s Disease:
Neuroleptic therapy (e.g. for schizophrenia)
Vascular insults (e.g. in the basal ganglia)
MPTP toxin from illicit drug contamination
Post-encephalitis e.g. influenza
Repeated head injury (i.e. boxing)
Familial Forms: genes implicated are LEEK2, PARK 2 (Parkin), PARK 7, PINK 1, SNCA (α-synuclein)
Summarise the epidemiology of Parkinson’s Disease
One of most common neurodegenerative disorders
Prevalence is 1% worldwide
Mean age of onset is 65 years old
More common in men
Young onset Parkinson’s Disease = in 21-40 year olds
What are the presenting symptoms of Parkinson’s Disease?
Insidious, often asymmetrical onset
Resting tremor mainly in hands Stiffness and slowness of movements Difficulty initiating movements Freezing of gait Postural instability - Frequent falls, imbalance Smaller hand writing (Micrographia) Mental slowness/slowness of thought (Bradyphrenia) Fatigue Constipation Dementia in mid to late-stage disease
What are the signs on physical examination of Parkinson’s Disease?
Pill rolling tremor at rest (4-6Hz): decreased on action, usually asymmetrical
Rigidity: ‘lead pipe rigidity’ of muscle tone: enhanced by distraction. Cogwheel rigidity
Gait: shuffling, stooped, small-stepped, reduced arm swing, difficulty initiating walk
Postural Instability: Falls easily with little pressure from the back or the front
Psychiatric: Depression & Cognitive issues and Dementia
Expressionless hypomimic face
Soft monotonous voice (Hypophonia)
Tendency to drool
Mild-impairment of up-gaze
Impaired olfaction
What are the appropriate investigations in Parkinson’s Disease?
Mainly a clinical diagnosis
Dopaminergic agent trial if questioning diagnosis (LEVODOPA TRIAL) - will notice improvement in symptoms
MRI brain if atypical features present - exclude other causes eg hydrocephalus
Dopamine transporter imaging to distinguish from Vascular Parkinson’s
Olfactory and Genetic testing to confirm diagnosis
Bloods: Serum caeruloplasmin: rule out Wilson’s disease as a cause of Parkinson’s disease (would be low if this was the case)
24hr urine copper test - elevated if Wilson’s disease if the cause
What is the management of Parkinson’s Disease?
Medical: symptomatic therapy by dopamine replacement i.e. levodopa, dopamine receptor agonist, COMT inhibitors, anti-cholinergic, MAO-B inhibitors.
Domperidone is used to treat nausea & vomiting
Surgical: Deep Brain Stimulation (only moderate-severe)
Other: physio, SALT, OT to improve QOL, encourage physical activity
What are the possible complications of Parkinson’s Disease?
Levodopa-induced dyskinesias - need to lower medication doses or increase dosing intervals Motor fluctuations Autonomic Dysfunction (postural hypotension, constipation, urinary retention) Death (usually due to pneumonia or PE) Dementia Psychosis Depression Anxiety
What is the prognosis of Parkinson’s Disease?
There are no curative or disease-modifying treatments
Progressive but variable in rate, with many patients having a normal life span
Optimal treatment can delay impact of disability by 5-10 years
Factors to predict more rapid rate of progression are:
Older age at symptom onset
Rigidity/hypokinesia as presenting symptoms (versus rest tremor)
Associated comorbidities
Decreased response to dopaminergic medications.
Define Huntington’s Disease
An slowly progressive, autosomal dominant, neurodegenerative disorder characterised by chorea, cognitive decline, loss of coordination and personality change. It is a trinucleotide repeat disorder and typically appears in mid-adult life.
Explain the aetiology/risk factors of Huntington’s Disease
Huntingtin gene codes for a protein called huntingtin
Huntington’s disease is caused by an expanded CAG repeat at the N-terminus of the gene that codes for the huntingtin protein.
Huntington’s shows anticipation - earlier age of onset with each successive generation
Risk factors:
Expansion of the CAG repeat length at the N-terminal end of the huntingtin gene
Family history
Other genetic factors
Summarise the epidemiology of Huntington’s
Prevalence is 4-8 per 100,000.
Duration of disease - 20 years from time of diagnosis to death.
Affects men and women equally
Onset usually 35-45 years old
What are the presenting symptoms of Huntington’s?
INSIDIOUS onset in middle-age of progressive fidgeting and clumsiness
Involuntary, jerky, dyskinetic movements often accompanied by grunting and dysarthria (twitching/restlessness)
Lability (rapid, often exaggerated changes in mood: irritability/temper outbursts)
Dysphoria (a state of unease or generalised dissatisfaction with life)
Mental inflexibility (may make unusual purchases, snap decisions, gambling)
Anxiety
Dementia
Loss of coordination - dropping things, stumbling, motor vehicle accidents
IN LATER STAGES: rigid, akinetic & bed-bound
What are the signs on physical examination of Huntington’s?
Chorea: random movement of fingers & toes, odd facial expressions, occasional peculiar postures of hand, trunk or limbs are typical of early disease
Dysarthria
Deficit in fine motor coordination - slow irregular tempo when asked to tap finger
Slow voluntary saccades and supranuclear gaze restriction (slowed rapid eye movements)
Motor impersistence - cannot protrude tongue fully or close eyes tightly for 10 seconds
Parkinsonism and Dystonia (uncontrollable muscle contraction)
MMSE shows cognitive and emotional deficits
What are the appropriate investigations for Huntington’s?
The diagnosis is usually CLINICAL so requires no tests
CAG repeat testing - more than 40 repeats on one of the alleles is a positive result, 36 to 39 repeats means they may or may not develop symptoms
MRI or CT scan - evident caudate or striatal atrophy
Define cluster headache
A neurological disorder characterised by recurrent, severe headaches on one side of the head typically around the eye, tending to recur over a period of several weeks.
Unilateral headache attacks lasting 15 minutes to 3 hours, associated with parasympathetic hyperactivity and sympathetic hypoactivity.
Pain is often localised to the unilateral orbital, supra-orbital, and/or temporal areas and can occur from once every other day to 8 times per day.
Explain the aetiology/risk factors of cluster headaches
Aetiology is unknown
Associated factors: Head trauma Heavy cigarette smoking Heavy alcohol intake Sleep apnoea - treatment of apnoea improves headache control
Risk factors: Male sex Family history Head Trauma Cigarette smoking Heavy drinking
Summarise the epidemiology of cluster headaches
Affects predominantly men
1 in 500 people
Age of onset between 20 and 40 years old
What are the presenting symptoms of cluster headaches?
Repeated attacks of unilateral pain around the eye which peaks within minutes and lasts 15 minutes to 3 hours
Autonomic symptoms: ipsilateral lacrimation, rhinorrhoea, partial Horner’s syndrome, nasal congestion, eye lid swelling, facial swelling, flushing
Nausea and vomiting
Photophobia and phonophobia
Migranous aura
Agitation - unable to stay still during an attack, pacing, banging head on wall
Suicidal thoughts
Headaches lasting 6-12 weeks at the same time each year every 1-2 years
Often occur at night 1-2 hours after falling asleep
What are the two types of cluster headache?
- Episodic: occurring in periods lasting 7 days-1 year, separated by pain-free periods lasting a month or longer. Cluster periods usually last between 2 weeks-3 months.
- Chronic: occurring for 1 year without remissions or with short-lived remissions of less than a month. Chronic cluster headaches can arise de novo or arise from episodic cluster headaches.
What are the signs on physical examination of cluster headache?
Evidence of autonomic symptoms ie eye lid or facial swelling
What are appropriate investigations for cluster headaches?
CLINICAL DIAGNOSIS - investigations are to rule out other causes.
Brain CT or MRI - normal if primary cluster headache. Allows elimination of secondary causes.
ESR - normal in cluster headache. Used to eliminate giant cell arteritis in patients over 50 y/o.
Pituitary function tests (TFTs, LH, FSH, cortisol, prolactin etc in bloods) - normal in primary cluster headache. Allows exclusion of pituitary adenoma as secondary cause.
ECG - exclude conduction abnormality before starting CCB
Define migraine
Migraine is a chronic, genetically determined, episodic, neurological disorder that usually presents in early-to-mid life. It is characterised by nausea, photophobia, and disability, along with headache and often has a preceding aura.
Explain the aetiology/risk factors of migraine?
Brain hyperexcitability to various stimuli
Neuronal depolarisation is believed to be the precipitating event in migraine aura
Risk factors: Family history of migraines High caffeine intake Exposure to change in barometric pressure (altitude and weather changes) Female Obesity Habitual snoring Stress Overuse of headache medication Lack of sleep OCP Allergies or asthma Hypertension Hypothyroidism Diet (alcohol, cheese, chocolate)
Summarise the epidemiology of migraines
High prevalence - 14% of individuals
More likely in females (3:1 F:M)
Prevalence rises in early adult years then decreases in late 40s-50s
More common in white patients
Highest amongst low income patients
Highest in Americas and Europe, lowest in Asia
What are the presenting symptoms of migraine?
Prolonged headache - 4-72 hours, may be throbbing
Nausea/vomiting
Decreased ability to function
Sensitivity to light
Headache made worse by activity - distinguish between migraine and tension headache (tension not worsened by exertion)
Sensitivity to noise
Aura: Visual disturbances (Flashing lights, Spots, Blurring, Zigzag lines, Blind Spots), Other sensory symptoms (tingling or numbness in limbs)
What are the signs on physical examination of migraine?
Nil signs of note
What are the appropriate investigations for migraine?
Mainly a clinical diagnosis from the history
Investigations to rule out other causes:
ESR - if raised, suggests temporal arteritis
Lumbar puncture - if abnormal could be SAH, meningitis or low or high cerebrospinal fluid pressure
CSF culture - if CNS infection
CT head/MRI brain - may show space-occupying lesion, ischaemic lesions, SAH
What is the management of migraine?
Acute with persistent symptoms: paracetamol, codeine, anti-emetics, triptans (5-HT agonists) eg sumatriptan, high flow oxygen, IV corticosteroid (NSAIDs)
Prophylaxis (if > 2 months): β-blockers, Amitriptyline, Topiramate, Sodium Valproate (tricyclic antidepressants, anticonvulsants)
Menstrual migraines can be controlled with the oral contraceptive pill
Advice: Encourage Regular meals and Sleep Caffeine Restriction Measures to Reduce Stress Symptom Diary Avoid triggers Rest in quiet, dark room during episodes
What are the possible complications of migraines?
Disruption of daily activities
Can progress into analgesia-overuse headaches in people who use analgesia regularly
Status migrainosus - migraine occurring for more than 72 hours
Migranous infarction - occurs when an aura lasts more than 1 hour
Migraine-triggered seizures
Depression
Chronic migraine - 15 or more days per month for more than three months with no medication overuse
Persistent aura without infarction
What is the prognosis of migraine?
Patients do well with treatment
The frequency of migraines decreases with age
Usually chronic
Define transient ischaemic attack
Sudden onset of neurological signs and symptoms caused by focal brain, spinal cord or retinal ischaemia (temporary occlusion of part of cerebral circulation) without acute infarction which resolves completely within 24 hours.
Summarise the aetiology of TIA
Most common cause = carotid artery stenosis
Cardioembolic events:
Carotid atherosclerosis
Emboli can arise from the heart: AF, atrial myxoma, mitral valve disease
Small vessel occlusion: microatheromas, fibrinoid necrosis
Others: occlusion due to hypercoagubility, dissection, vasculitis, vasospasm
What are the risk factors for TIA?
HYPERTENSION AF Coronary Artery Disease Diabetes Increasing age Male Obesity Hypercholesterolaemia Family history Valvular disease Smoking Alcohol
Summarise the epidemiology of TIA
2000 people per year in England have first TIA
Prevalence increases with age
More common in men
Less common in white patients
What are the presenting symptoms of TIA?
Clinical features depend on the part of the brain affected:
Carotid Territory:
Unilateral
Affect the MOTOR AREA
Weakness of arm, leg or one side of the face
Dysarthria
Broca’s dysphasia
Amaurosis fugax (painless fleeting loss of vision caused by retinal ischaemia)
Vertebrobasilar Territory: Homonymous hemianopia (if ophthalmic cortex is involved) Bilateral visual impairment Hemiparesis Hemisensory symptoms Diplopia Vertigo Vomiting Dysarthria Dysphagia Ataxia
What are the signs on physical examination of TIA?
Neurological examination may be NORMAL because the TIA may have resolved
Check pulse for irregularly irregular rhythm (AF)
Carotid bruit (carotid atherosclerosis)
Elevated BP (rises acutely after a cerebral ischaemic effect by increasing cerebral blood flow)
What are the appropriate investigations for TIA?
Bloods:
Glucose - hypoglycaemia can cause similar symptoms
FBC
ECG - check for AF
MRI brain - may show infarct
Carotid doppler ultrasound if expecting carotid stenosis
MR/CT angiography to further investigate carotid stenoses
Echo - check for valvular disease
What is the management of TIAs?
Patient presenting with suspected TIA = 300mg aspirin immediately and assess urgently within 24 hours
Patients with confirmed TIA should receive:
Clopidogrel: 300 mg loading dose and 75 mg thereafter
High-Intensity Statin Therapy: e.g. atorvastatin 20-80 mg
Secondary Prevention: ANTI-PLATELETS EG ASPIRIN ANTIHYPERTENSIVES (hypertension is biggest RF) Lipid-modifying treatments Management of AF Life style modification
Carotid endarterectomy (artery opened and clot removed) IF:
>70% stenosis
Symptomatic TIA or good recovery stroke in past 6 months involving anterior cirulation
Assessment of future stroke risk in TIA patients: ABCD2 score
Age >60
Blood pressure - systolic >140mmHg
Clinical - unilateral weakness (2), speech deficit (1)
Duration of symptoms - >60mins (2), 10-59mins (1)
Diabetes
0-3 = 1% 2 day stroke risk 4-5 = 4.1% risk 6-7 = 8.1%
What are the possible complications of TIA?
Recurrent TIA
Stroke
MI
What is the prognosis of TIA?
> 10% seen in A&E will have stroke within 3 months
Define Bell’s palsy
An acute unilateral, idiopathic facial nerve palsy, likely of viral aetiology. It is a peripheral/LMN lesion.
Summarise the aetiology of Bell’s Palsy
It is idiopathic
Likely a viral aetiology - most likely HERPES SIMPLEX VIRUS
May be EBV or Varicella Zoster
60% are preceded by an upper respiratory tract infection
What are the risk factors for Bell’s palsy?
Intranasal influenza vaccination Pregnancy (3 times more common) Upper Respiratory Tract Infection Family history Diabetes Hypertension
Summarise the epidemiology of Bell’s palsy
Most common aetiology of unilateral facial palsy
Most prevalent between 15-45y/o
Equal distribution between both sexes
What are the presenting symptoms of Bell’s palsy?
Preceding ear pain (1-2 days before) Rapid onset symptoms Unilateral facial muscle weakness/paralysis Drooping eyelid and mouth Dry mouth and eyes Difficulty closing eye Loss of taste sensation Phonophobia Speech impairment Drooling saliva
What are the signs on physical examination of Bell’s palsy?
LMN weakness of facial muscles:
Affects IPSILATERAL muscles of facial expression
Does NOT spare the muscles of upper part of the face (unlike UMN facial nerve palsy)
Bell’s Phenomenon - Eyeball rolls up but the eye remains open when trying to close their eyes
Clinical testing of sensation is NORMAL
Examine the ears to check for other causes of facial nerve palsy (e.g. otitis media, herpes zoster infection)
BELL’S PALSY IS DIAGNOSIS OF EXCLUSION
What are the appropriate investigations for Bell’s palsy?
Mainly a CLINICAL DIAGNOSIS - acute unilateral facial weakness with normal physical exam
Viral serology
Nerve conduction studies if palsy consists to rule out axonal degeneration
EMG: may show absence of voluntary motor unit potentials
Serology for Borrelia Burgdorferi: indicated in patients with travel to Lyme Disease endemic area
What is the management of Bell’s palsy?
ALL PATIENTS:
Protection of cornea with protective glasses/patches or artificial tears
High-dose corticosteroids within 72 hrs i.e. short dose oral prednisolone
Adjuncts:
Concurrent Antiviral Therapy
Encourage closure of eyelids by hand or tape at night
Surgical decompression - lateral tarsorrhaphy (suturing the lateral parts of the eyelids together) – performed if imminent or established corneal damage
What are the possible complications of Bell’s palsy?
Corneal ulcers Dry Eyes Eye Infection Aberrant reinnervation (synkinesis) Gustatory Hyper lacrimation (PNS fibres may aberrantly reinnervate the lacrimal glands causing tearing whilst salivating)
Summarise the prognosis of Bell’s palsy
Extent of facial palsy within 72 hours is predictive of recovery outcome
94% with incomplete paralysis will recover, 61% with complete paralysis will recover
Pregnancy-associated Bell’s palsy has worse outcomes
Recovery within 2-12 weeks
Define Guillain-Barre syndrome
An acute segmental demyelinating disease of the peripheral nervous system
ACUTE INFLAMMATORY DEMYELINATING POLYNEUROPATHY
Summarise the aetiology of Guillain-Barre syndrome
Cause unknown
Immune mediated attack where antibodies formed after a recent infection react with self-antigens on myelin sheath or Schwann cells
Often develops post:
Bacterial infection - campylobacter jejuni, mycoplasma pneumoniae
Viral infection - CMV, EBV
Preceded by gastroenteritis or flu like symptoms within 6 weeks of symptoms
Rarely triggered following influenza vaccination
What are the risk factors of Guillain-Barre syndrome?
Previous viral illness
Bacterial infection
Hepatitis E
Mosquito-borne viral infection
Summarise the epidemiology of Guillain-Barre syndrome
Slightly more common in males
Mean age of presentation is 40
Affects all age groups
What are the presenting symptoms of Guillain-Barre syndrome?
Progressive symptoms
Initially ascending symmetrical paresthesia - loss of vibration and touch sensation
Ascending symmetrical muscle weakness/paralysis (more in upper limb and more proximal)
Cranial nerve involvement - dysphagia, dysarthria, facial weakness, diplopia, difficulty speaking
Respiratory muscles may be affected in SEVERE cases -dyspnoea on exertion & SOB
Autonomic nerve involvement - palpitations, constipation, urinary incontinence
What are the signs on physical examination of Guillain-Barre syndrome?
Hypotonia
Flaccid paralysis
Areflexia/hyporeflexia (ascending upwards from feet to head - notice loss of ankle reflex first)
Impairment of sensation in multiple modalities (ascending from feet to head)
Facial nerve weakness - slurred speech
Abnormality of external ocular movements due to extra-ocular muscle weakness
Type II Respiratory Failure due to paralysis of respiratory muscles:
CO2 retention flap
Bounding pulse
Autonomic Function:
Orthostatic hypotension
BP fluctuations
Arrhythmia
What are the appropriate investigations for Guillain-Barre syndrome?
Lumbar puncture - high CSF protein/albumin with normal WBC and glucose (ALBUMINOCYTOLOGIC DISSOCIATION)
Nerve conduction tests - reduced conduction velocity
Pulmonary function tests (spirometry) - reduced FVC suggests ventilator weakness
Bloods: LFTs (may be elevated), Anti-ganglioside antibodies in Miller-Fisher variant
ECG: Arrhythmias may develop
Define trigeminal neuralgia
A neuropathic facial pain syndrome in the distribution of one or more branches of the trigeminal nerve.
Summarise the aetiology of trigeminal neuralgia
Associated with trigeminal nerve root compression at the root entry zone by a vascular loop - often by SUPERIOR CEREBELLAR ARTERY
Systemic causes:
MS
Expanding cranial tumour
What are the risk factors of trigeminal neuralgia?
Increased Age
Multiple sclerosis
Female
Hypertension
Summarise the epidemiology of trigeminal neuralgia
More common in feamles
Peak 50-60 years old
4-13 per 100,000
Prevalence increases with age
What are the presenting symptoms of trigeminal neuralgia?
Paroxysms of sudden, sharp, shooting, UNILATERAL facial pain lasting less than 2 minutes
Pain lasts from seconds to 2 minutes
Pain is in trigeminal distribution
Pain bought on by brushing teeth, chewing, shaving, breeze, touching area etc
Recurrent & Periods of remission can vary
Some experience preceding symptoms (e.g. numbness, tingling
What are the signs on physical examination of trigeminal neuralgia?
MAY have sensory/motor changes - suggestive of pathological cause
NO VISION LOSS
NO ASSOCIATED NEUROLOGICAL DEFICIT
What are the appropriate investigations for trigeminal neuralgia?
CLINICAL DIGANOSIS so usually no investigations
If there is doubt over the underlying cause, specialists may request an:
Intra-oral X-ray: if dental cause of pain is suspected
MRI brain scan: if history or examination suggests other pathology
Trigeminal Reflex Testing: abnormal reflexes suggestive of symptomatic trigeminal neuralgia
Define myasthenia gravis
A chronic autoimmune condition affecting the post-synaptic membrane of neuromuscular junctions of skeletal muscles due to autoantibodies usually against nicotinic acetylcholine receptors. This causes muscle weakness and fatiguability.
Summarise the aetiology of myasthenia gravis
Impairment on NMJ transmission
Autoantibodies against nicotinic acetylcholine receptors on postsynaptic membrane at NMJ preventing muscle contraction - 80-90% of patients
Minority of patients have muscle specific receptor tyrosine kinase anitbodies - 3-7%
May present as paraneoplastic syndrome - associated with thymoma and bronchogenic carcinoma
Associated with thymic follicular hyperplasia
Associated with other AI conditions (e.g. pernicious anaemia)
Lambert-Eaton Syndrome: paraneoplastic subtype of myasthenia gravis caused by autoantibodies against pre-synaptic calcium channels, leading to impairment of acetylcholine release
Summarise the epidemiology of myasthenia gravis
There is a bimodal distribution
Young women aged 20-30
Older men aged 60-70
Affects women more than men
MG with muscle-specific tyrosine kinase antibodies has 80-90% of patients as women. It is more common in black women and usually affects at mid-30s
What are the presenting symptoms of myasthenia gravis?
Diplopia
Ptosis
Muscle weakness which worsens with repetitive movement or exercis - FATIGUABILITY
Muscle weakness gets better on resting
Usually wakes up fine
Dysphagia
Dysarthria
Facial paresis
Shortness of breath
Disturbed, characteristic hyper nasal speech (dysarthria)
Difficulty smiling, chewing or swallowing (nasal regurgitation of fluids)
What are the signs on physical examination of myasthenia gravis?
May be generalised (affecting many muscle groups), bulbar or ocular
Bilateral ptosis
Complex ophthalmoplegia
Check for ocular fatigue by asking the patient to sustain and upward gaze for 1 minute and watch the progressive ptosis that develops
Reading aloud can provoke dysarthria or nasal speech
Limbs: test power of muscle before & after repeated use (muscle fatiguability)
What are the appropriate investigations for myasthenia gravis?
Serum acetylcholine receptor autoantibodies - positive in 80-90% of patients
Muscle specific receptor tyrosine kinase antibodies
TFTs (associated with hyperthyroidism)
Anti-voltage gated Ca channel antibody (in Lambert-Eaton syndrome)
Serial pulmonary function tests: indicated if patient has SOB & suspected MG crisis
Repetitive nerve stimulation: reduced muscle action potential
Single Fibre EMG
CT Thorax/CXR: visualise thymoma (thymic enlargement) in mediastinum/lung malignancy
NERVE CONDUCTION STUDY = GOLD STANDARD DIAGNOSTIC TEST
Define Horner’s syndrome
A syndrome caused by interruption of the sympathetic nerve supply to one side of the face, resulting in the triad of ptosis, miosis and anhydrosis.
Summarise the aetiology of Horner’s syndrome
Caused by disruption of the sympathetic nervous system supply to the face
Damage to 1st order neurone:
Tumour
Syringomyelia
Stroke
Damage to 2nd order neurone:
Apical lung tumour (pancoast tumour)
Damage to 3rd order neurone:
Internal carotid artery dissection
Other:
Neck trauma
MS
Lymphadenopathy
Summarise the epidemiology of Horner’s syndrome
Rare
It is a sign associated with many conditions
What are the presenting symptoms of Horner’s syndrome?
Unable to open one eye fully Loss of sweating on affected side Facial flushing Orbital pain/headache Other symptoms based on CAUSE
What are the signs on physical examination of Horner’s syndrome?
Unilateral ptosis
Unilateral anhidrosis
Unilateral myosis
Enopthalmos
Symptoms are on ipsilateral side as lesion
Can have decreased visual acuity and/or abnormal eye movement which warrants further investigation
What are the appropriate investigations for Horner’s syndrome?
Cocaine eye drop:
Usually causes build up of NA by preventing reuptake which would cause dilation
If no dilation - suggests Horner’s
Apraclonidine eye drop:
Weaker form of cocaine which normally does not cause dilation
If dilation of eye occurs - suggests Horner’s
CT/MRI - find underlying cause eg cerebrovascular accident
CXR: apical lung tumour
CT angiography: dissection
What is the management of Horner’s syndrome?
Depends on the underlying cause of Horner’s
Surgical intervention is needed for syringomyelia, tumours, or carotid artery dissection
Define hydrocephalus
Hydrocephalus is enlargement of the ventricular system of the brain due to excessive build up of CSF. It can be communicating or non-communicating
Summarise the aetiology of hydrocephalus
Abnormal accumulation of CSF in the ventricles can be caused by:
Impaired outflow of the CSF from the ventricular system: OBSTRUCTIVE
Lesions of the 3rd and 4th ventricle or cerebral aqueduct
Posterior fossa lesions (e.g. tumour) compressing the 4th ventricle
Cerebral aqueduct stenosis
Impaired CSF reabsorption into the subarachnoid villi: NON-OBSTRUCTIVE
Tumours
Meningitis
Normal Pressure Hydrocephalus: idiopathic chronic ventricular enlargement. The long white matter tracts are damaged leading to gait and cognitive decline.
Summarise the epidemiology of hydrocephalus
There is a bimodal age distribution
Young: due to congenital malformations and brain tumours
Elderly: due to strokes and tumours
Summarise the presenting symptoms of hydrocephalus
Obstructive hydrocephalus:
Diplopia
Acute decrease in consciousness
Normal pressure hydrocephalus: Urinary incontinence Falls Abnormal walking Struggle to lift foot to initiate walking Memory loss Personality change Slow thought processing
What are the signs on physical examination of hydrocephalus?
Obstructive Hydrocephalus:
Low GCS
Papilledema
6th Nerve Palsy (6th nerve has the longest intracranial path of all the CN & so is most susceptible to palsy due to raised ICP)
Normal Pressure Hydrocephalus:
Cognitive impairment
Gait apraxia (wide based, shuffling)
Hyperreflexia
Neonates: Increased head circumference and Sunset sign (↓ conjugate deviation of the eyes)
What are the appropriate investigations for hydrocephalus?
CT Head: 1st line for detecting hydrocephalus, may show cause (e.g. tumour).
CSF: obtained from ventricular drain or lumbar puncture
May indicate pathology (e.g. tuberculosis)
Check MC&S, protein and glucose.
Lumbar Puncture:
CONTRAINDICIATED IF RAISED ICP as can cause tonsillar herniation & death.
Therapeutic in normal pressure hydrocephalus.
Define subarachnoid haemorrhage
Bleeding into the subarachnoid space (space between pia mater and arachnoid mater) and it is an emergency
Summarise the aetiology of subarachnoid haemorrhage
Traumatic injury Saccular anuerysm rupture - main non-traumatic cause 80% Arteriovenous malformation Peri mesencephalic SAH Bleeding diathesis Vertebral artery dissection Use of anticoagulants
Risk factors: Alcohol Smoking Family history Hypertension Autosomal dominant kidney disease Connective tissue disease eg Marfan's (predispose to aneurysm formation)
Summarise the epidemiology of subarachnoid haemorrhage
Incidence increases with age Average age of onset 50-55 years old More common in women More common in black patients Accounts for 5% of all strokes
What are the presenting symptoms of subarachnoid haemorrhage?
Sudden onset, thunderclap, worst headache ever Photophobia Vomiting Neck stiffness Visual changes Confusion Seizures Reduced level of consciousness
What are the signs on physical examination of subarachnoid haemorrhage?
Reduced consciousness
Meningism: Neck stiffness, Kernig’s sign, Pyrexia
Signs of raised ICP - papilledema, IV or III nerve palsies, hypertension, bradycardia
Focal neurological signs (e.g. cranial nerve palsies: CN III palsy indicates presence of posterior communicating artery aneurysm compressing CN III)
What are the appropriate investigations for subarachnoid haemorrhage?
Non-contrast CT head - show bleeding (hyperdensity) within subarachnoid space, sensitivity decreases with time
If CT normal but high suspicion - Lumbar puncture:
Shows yellow xanthochromia. Must be performed more than 12 hours after onset. Take 3 tubes.
FBC - leukocytosis
Serum sodium - may be low
Cerebral angiography can identify causal pathology
CRP/ESR
Clotting Profile (elevated INR, prolonged PTT)
Cardiac Enzymes (troponin).
ECG: Patients with SAH will have an abnormal ECG on admission i.e. arrythmias, prolonged AT, ST segment or T wave abnormalities.
Define Wernicke’s encephalopathy
An acute neurological, reversible emergency caused by thiamine (vit B1) deficiency, leading to a triad of confusion, ophthalmoplegia and ataxia which must be treated immediately to prevent chronic irreversible neurological changes.
Summarise the aetiology of Wernicke’s encephalopathy
Due to low thiamine causing CNS lesions
Decreased thiamine intake - malnutrition, anorexia
Decreased absorption - stomach cancer, IBD
Chronic alcohol consumption
Chronic alcohol consumption is the main cause:
Liver cirrhosis prevents storage of thiamine
Decreased absorption
Prevents conversion to active form
Inadequate nutritional thiamine intake
Other causes: Chronic subdural haematoma AIDS Hyperemesis Gravidarum Thyrotoxicosis
What are the risk factors of Wernicke’s encephalopathy?
Alcohol Dependence AIDS Chemotherapy Malnutrition History of GI Surgery
Summarise the epidemiology of Wernicke’s encephalopathy
Worldwide prevalence between 0.8-2.8%
Prevalence higher in males
Prevalence higher in patients with alcohol dependence, AIDS and bone marrow transplantation
Higher prevalence in 50-60 year olds
What are the presenting symptoms of Wernicke’s encephalopathy?
Ophthalmoplegia - weakness of eye muscles
Ataxia - unsteady gait and loss of muscle coordination
Confusion
Loss of consciousness
Vision changes: diplopia, eye movement abnormalities, ptosis
Loss of memory and Inability to form new memories
Hallucinations
Impaired concentration
What are the signs on physical examination of Wernicke’s encephalopathy?
TRIAD OF ATAXIA, OPHTHALMOPLEGIA AND CONFUSION
Mental slowing, impaired concentration & apathy
Ocular Motor Findings: gaze palsies, CNVI Palsy, Impaired Vestibulo-Ocular Reflex
Papilledema, Retinal Haemorrhages
Tachycardia AND/OR Hypotension
Hypothermia or Hyperthermia
Coma - decreased GCS
What are the appropriate investigations for Wernicke’s encephalopathy?
Diagnosis is mainly based on history and examination
Serum thiamine - LOW
FBC (high MCV is a common feature amongst alcoholics)
U&Es (exclude metabolic imbalances as a cause of confusion)
LFTs (elevated if due to chronic alcohol use)
Glucose
Blood alcohol level
ABG (hypercapnia and hypoxia can cause confusion)
Other: CT head, MRI Brain (show degeneration of mammillary bodies), Lumbar Puncture (exclude other pathology)
