Neurology Flashcards
What is MS?
MS is an acquired, immune-mediated inflammatory condition that affects both the brain and spinal cord.
It does not affect the peripheral nervous system.
MS is commoner in women
Typically occurs in temporal regions. Symptoms typically commence in early life (20s and 30s) in the form of visual or sensory disturbances.
Weakness and clumsiness of the limbs combined with bladder symptoms are common.
Typically the early symptoms will relapse and remit but over time progressive disability will occur.
It is thought to be an abnormal immune response to environmental triggers in people who are genetically predisposed.
It leads to immune-mediated demyelination in CNS neurones and ultimately nerve cell degeneration.
What are the variants of MS?
There are 3 main patterns of clinical presentation:
- Relapsing remitting.
- Secondary progressive.
- Primary progressive.
What is relapsing remitting MS?
Symptoms come and go. Periods of good health or remission are followed by sudden symptoms or relapses (80% of people at onset).
What is secondary progressive MS?
Follows on from relapsing-remitting MS. There are gradually more or worsening symptoms with fewer remissions (about 50% of those with relapsing-remitting MS develop secondary progressive MS during the first ten years of their illness).
What is primary progressive MS?
From the beginning, symptoms gradually develop and worsen over time (10-15% of people at onset).
Clinical presentation of MS
Optic neuritis.
Double vision.
Sensory disturbance in face or limbs.
Weakness due to upper motor neurone involvement.
Impaired balance between or clumsiness of the limbs.
Neuropathic pain (e.g. trigeminal neuralgia).
Bladder symptoms.
Cognitive impairment ( although this usually occurs late)
Presentation of optic neuritis
A visual disturbance evolves over a few days with distortion of the central vision and impairment of COLOUR perception.
There may be PAIN on eye movement.
VISUAL LOSS can be mild to severe.
Patients have a relative afferent pupillary defect and a CENTRAL SCOTOMA. .
The optic disc usually appears normal though may be swollen with papillitis.
Vision improves over months, though may be incomplete, particularly if visual loss was severe initially.
Optic atrophy may develop following an episode of optic neuritis
Trigeminal neuralgia - features
Trigeminal neuralgia symptoms may include one or more of these patterns:
- UNILATERAL
- Episodes of severe, shooting or jabbing PAIN that may feel like an ELECTRIC shock
- Spontaneous attacks of pain or attacks triggered by things such as touching the face, chewing, speaking or brushing teeth, washing, shaving, and frequently occurs SPONTANEOUSLY
- Bouts of pain lasting from a few seconds to several minutes - abrupt in onset and termination
- Pain in areas supplied by the trigeminal nerve, including the cheek, jaw, teeth, gums, lips, or less often the eye and forehead
- small areas in the nasolabial fold or chin may be particularly susceptible to the precipitation of pain (trigger areas)
- the pains usually remit for variable periods
Aetiology of MS
It is thought to be an abnormal immune response to environmental triggers in people who are genetically predisposed.
It leads to immune-mediated demyelination in CNS neurones and ultimately nerve cell degeneration. Initially, after the acute inflammatory stage, neurones may remyelinate and recover leading to
clinical remission. Recurrent episodes eventually lead to neuronal degeneration that, in turn, will produce a permanent clinical deficit.
Features of temporal lobe seizures?
(HEAD)
Hallucinations (auditory/gustatory/olfactory), Epigastric rising/Emotional, Automatisms (lip smacking/grabbing/plucking), Deja vu/Dysphasia post-ictal)
Features of Frontal lobe seizures?
(motor)
Head/leg movements, posturing, post-ictal weakness, Jacksonian march
Features of parietal lobe seizure ?
(sensory)
Paraesthesia
Features of occipital lobe seizure?
(visual)
Floaters/flashes
What is a juvenile myoclonic epilepsy?
Juvenile myoclonic epilepsy is a genetic GENERALISED epilepsy syndrome including ABSENCE, MYOCLONIC and generalised TONIC-CLONIC seizures.
Features of Extradural haemorrhage?
Usually caused by trauma - typically ‘low impact’
Usually in the TEMPORAL region as the thin skull at he pterion overlies the middle meningeal artery - venerable to injury
Appears as a biconvex on CT
Lucid interval
Tx of extradural haematoma?
Craniotomy and evacuation of the haematoma
Complication of extradural haematoma
As the haematoma expands the uncus of the temporal lobe HERNIATES around the tentorium cerebelli and the patient develops a FIXED and DIALTED pupil due to the compression of the parasympathetic fibers of the third cranial nerve.
Management of migraine during pregnancy
- paracetamol 1g is first-line
- aspirin 300mg or ibuprofen 400mg can be used second-line in the first and second trimester
Management of Migraine and the combined oral contraceptive (COC) pill?
If patients have migraine with aura then the COC is absolutely CONTRAINDICATED due to an increased risk of STROKE (relative risk 8.72)
Management of Migraine and menstruation?
Many women find that the frequency and severity of migraines increase around the time of menstruation
SIGN recommends that women are treated with MEFANAMIC ACID or a combination of aspirin, paracetamol and caffeine. TRIPTANS are also recommended in the acute situation
Management of Migraine and hormone replacement therapy (HRT)?
safe to prescribe HRT for patients with a history of migraine but it may make migraines worse
Left homonoymous hemianopia with macular sparing?
lesion at occipital cortex
As there is macular sparing, lesion likely to be at occipital cortex rather then optic tract
Bitemporal hemianopia
Lesion at the optic chiasm
e.g. patient could have a pituitary tumour causing compression of the optic chiasm and bitemporal hemianopia.
Secondary to acromegaly - have sweating and headaches (acromegaly is a hormonal disorder that develops when your pituitary gland produces too much growth hormone during adulthood)
family history of early blindness
developing ‘tunnel vision’.
??
Retinitis pigmentosa
Extensive pigmentations would be noted on fundoscopy
Visual field defects
- Left homonymous hemianopia means visual field defect to the left, i.e. Lesion of right optic tract
- Homonymous quadrantanopias: PITS (lesion in Parietal-Inferior, lesion in Temporal-Superior)
- incongruous defects = optic tract lesion; congruous defects = optic radiation lesion or occipital cortex
Neuropathic pain- examples
Neuropathic pain may be defined as pain which arises following damage or disruption of the nervous system. It is often difficult to treat and responds poorly to standard analgesia.
Examples include:
- diabetic neuropathy
- post-herpetic neuralgia
- trigeminal neuralgia
- prolapsed intervertebral disc
Management of neuropathic pain
first-line treatment*:
- amitriptyline, duloxetine, gabapentin or pregabalin
- if the first-line drug treatment does not work try one of the other 3 drugs
- tramadol may be used as ‘rescue therapy’ for exacerbations of neuropathic pain
- topical capsaicin may be used for localised neuropathic pain (e.g. post-herpetic neuralgia)
- pain management clinics may be useful in patients with resistant problems
*please note that for some specific conditions the guidance may vary. For example carbamazepine is used first-line for trigeminal neuralgia
Patients who present with falls soon after a diagnosis of Parkinson’s disease… what to do?
Investigate for alternative diagnoses.
- initial investigation - assessment of CN III,IV and VI
This is because a common sign of PSP (progressive supranuclear palsy), the most likely alternative diagnosis (and a ‘Parkinson’s plus’ syndrome), commonly manifests with a VERTICAL SUPRANUCLEAR GAZE PALSY.
Even if the diagnosis is not PSP, assessment of cranial nerves should be performed in anyone who presents with a fall.
Progressive supranuclear palsy
aka Steele-Richardson-Olszewski syndrome
a ‘Parkinson Plus’ syndrome
Features
- impairment of VERTICAL GAZE (DOWN gaze worse than up gaze - patients may complain of difficultly reading or descending stairs)
- parkinsonism
- falls
- slurring of speech
- cognitive impairment
Management
- poor response to L-dopa
Cluster headache
They typically occur in clusters lasting several weeks, with the clusters themselves typically once a year.
Cluster headaches are more common in men (3:1) and smokers. ALCOHOL may trigger an attack and there also appears to be a relation to nocturnal SLEEP.
Features
- pain typical occurs once or twice a day, each EPISODE lasting 15 mins - 2 hours
- clusters typically last 4-12 weeks
- intense SHARP, stabbing pain around one eye (recurrent attacks ‘always’ affect same side)
- patient is restless and AGITATED during an attack
accompanied by REDNESS, LACRIMATION, lid swelling
nasal stuffiness
miosis and ptosis in a minority
Management of cluster headaches
Management
- acute: 100% oxygen (80% response rate within 15 minutes), SUBC triptan (75% response rate within 15 minutes)
triptans are contraindicated in patients with CAD as they have the potential to cause coronary vasospasm
- prophylaxis: verapamil is the drug of choice. There is also some evidence to support a tapering dose of prednisolone
NICE recommend seeking specialist advice from a neurologist if a patient develops cluster headaches with respect to neuroimaging
What is right?
To replace vit b12 first before folate or folate before vit b 12?
Always replace VITAMIN B12 BEFORE folate - giving folate to a patient deficient in B12 can precipitate SUBACUTE COMBINED DEGENERATION of the cord
Subacute combined degeneration of spinal cord
Due to vitamin B12 DEFICIENCY
- Dorsal + lateral columns affected
- Joint position and vibration sense lost first then distal paraesthesia
- upper motor neuron signs typically develop in the legs, classically extensor plantars, brisk knee reflexes, absent ankle jerks
- ## if untreated stiffness and weakness persistDamage to the posterior columns - loss of proprioception, light touch and vibration sense (sensory ataxia and a positive Romberg’s test).
Damage to lateral columns - spastic weakness and upgoing plantars (UMN signs).
Damage to peripheral nerves - absent ankle and knee jerks (LMN signs).
- When there is a mix of UMN and LMN signs in a patient, always consider SCDC.
------ Therefore the classic triad of symptoms is: 1. Extensor plantar response 2. Brisk knee jerks 3. Absent ankle jerks
What is Amyotrophic lateral sclerosis
A subtype of MND
May present with mixed UMN and LMN - no sensory deficits
Death of both upper and lower motor neurons in the motor cortex of the brain, the brain stem, and the spinal cord.
Myasthenia Gravis
Autoimmune disease affecting the neuromuscular junction so will NOT present with UMN signs or sensory loss.
Charcot-Marie-Tooth- features and overview
Charcot-Marie-Tooth disease is a hereditary SENSORY and MOTOR PERIPHERAL neuropathy. It results in a predominantly motor loss.
UMN signs are NOT present in these patients.
However, patients can present with LMN signs in all limbs and REDUCED SENSATION (more pronounced distally).
Charcot-Marie-Tooth Disease is the most common hereditary peripheral neuropathy
Features:
- There may be a history of frequently sprained ankles
- Foot drop
- High-arched feet (pes cavus)
- Hammer toes
- Distal muscle weakness
- Distal muscle atrophy
- Hyporeflexia
- Stork leg deformity
What needs to be considered when starting Phenytoin infusion?
CARDIAC monitoring is required due to the pro-arrhythmogenic effects it elicits.
Phenytoin
Phenytoin is used in the management of seizures.
Mechanism of action:
binds to sodium channels INCREASING their REFRACTORY PERIOD
Adverse effects:
Phenytoin is associated with a large number of adverse effects. These may be divided into acute, chronic, idiosyncratic and teratogenic.
Phenytoin is also an INDUCER of the P450 system.
Acute
- initially: dizziness, diplopia, nystagmus, slurred speech, ataxia
- later: confusion, seizures
- reduced sensation in a glove-and-stocking distribution
- reduced ankle reflex
Chronic
- common: gingival hyperplasia (secondary to increased expression of platelet derived growth factor, PDGF), hirsutism, coarsening of facial features, drowsiness
- megaloblastic anaemia (secondary to altered folate metabolism)
- peripheral neuropathy
- enhanced vitamin D
- metabolism causing osteomalacia
- lymphadenopathy
- dyskinesia
Idiosyncratic - fever - rashes, including severe - reactions such as toxic epidermal necrolysis hepatitis - Dupuytren's contracture* - aplastic anaemia - drug-induced lupus
Teratogenic
- associated with cleft palate and congenital heart disease
Monitoring
Phenytoin levels do not need to be monitored routinely but trough levels, immediately before dose should be checked if:
- adjustment of phenytoin dose
- suspected toxicity
- detection of non-adherence to the prescribed medication
*although not listed in the BNF
Normal pressure hydrocephalus - features
- Progressive mental impairment and dementia
- Difficulty walking
- Impaired bladder control
The gait disturbance is often the most noticeable symptom, it can resemble a parkinsonian gait but unlike Parkinson’s there is no rigidity or tremor.
Progressive supranuclear palsy
Starts with patients having IMPAIRED BALANCE and therefore being prone to many FALLS.
On examination, they have a VERTICAL GAZE PALSY. It has a SYMMETRICAL onset and is poorly responsive to levodopa, unlike Parkinson’s disease.
What does PSP stand for?
Progressive supra nuclear palsy
Corticobasal syndrome
Corticobasal syndrome begins as a MOVEMENT disorder, with a UNILATERAL ABSENCE of movements and muscle RIGIDITY with a TREMOR.
It is a progressive neurological disorder that can also affect cognition.
Multiple system atrophy
There are 2 predominant types of multiple system atrophy
1) MSA-P - Predominant Parkinsonian features
2) MSA-C - Predominant Cerebellar features
Shy-Drager syndrome is a type of multiple system atrophy.
Features
- parkinsonism
- autonomic disturbance (atonic bladder, postural hypotension, erectile dysfunction)
- cerebellar signs
Bulbar palsy
ONLY lower motor signs
UM signs are not present
Pseudobulbar palsy
Only present with UMN signs and not LMN signs.
Types of MND
Amyotrophic lateral sclerosis (50% of patients)
typically LMN signs in arms and UMN signs in legs
in familial cases the gene responsible lies on chromosome 21 and codes for superoxide dismutase
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
(note: MND can initially present with limb weakness, it is progressive so wont resolve in a couple days)
Spontaneous intracranial hypotension
Low CSF can occur due to spontaneous intracranial hypotension (not necessarily post-LP) and are classically WORSE ON STANDING and improve when lying flat
Lack of associated features, all the other types of headache can be excluded.
Results from a CSF leak. The leak is typically from the thoracic nerve root sleeves.
Risk factors include connective tissue disorders such as Marfan’s syndrome.
Investigations:
MRI with gadolinium: typically shows pachymeningeal enhancement
Management:
usually conservative
if this fails an epidural blood patch may be tried
Which parkinson drugs are most associated with impulse control disorder?
Dopamine receptor agonists are associated with the highest chance of inhibition disorders out of the antiparkinsonian medications
Levodopa
Usually combined with a decarboxylase inhibitor (e.g. carbidopa or benserazide) to PREVENT PERIPHERAL metabolism of levodopa to dopamine
- reduced effectiveness with time (usually by 2 years)
- unwanted effects: DYSKINESIA (involuntary writhing movements), ‘on-off’ effect, dry mouth, anorexia, palpitations, postural hypotension, psychosis, drowsiness
- no use in neuroleptic induced parkinsonism
- it is important not to acutely stop levodopa, for example if a patient is admitted to hospital. If a patient with Parkinson’s disease cannot take levodopa orally, they can be given a dopamine agonist patch as rescue medication to prevent acute dystonia
Bell’s palsy
An ACUTE, UNILATERAL, idiopathic, facial nerve PARALYSIS. The aetiology is unknown although the role of the herpes simplex virus has been investigated previously. The peak incidence is 20-40 years and the condition is more common in pregnant women.
Features:
- LOWER motor neurone facial nerve palsy - FOREHEAD AFFECTED
- patients may also notice post-auricular PAIN (may precede paralysis), altered TASTE, DRY eyes, HYPERACUSIS
Management:
- PREDNISOLONE 1mg/kg for 10 days should be prescribed for patients within 72 hours of onset of Bell’s palsy. Adding in aciclovir gives no additional benefit
- EYE CARE is important - prescription of ARTIFICIAL TEARS and eye lubricants should be considered
Prognosis:
if untreated around 15% of patients have permanent moderate to severe weakness
Autonomic dysreflexia
This clinical syndrome occurs in patients who have had a SPINAL CORD INJURY at, or above T6 spinal level.
Briefly, AFFERENT signals, most commonly triggered by faecal impaction or urinary retention (but many other triggers have been reported) cause a SYMPATHETIC SPINAL REFLEX via thoracolumbar outflow.
The usual, centrally mediated, parasympathetic response however is prevented by the cord lesion. The result is an unbalanced physiological response, characterised by EXTREME HTN, FLUSHING and SWEATING above the level of the cord lesion, agitation, and in untreated cases severe consequences of extreme hypertension have been reported, e.g. haemorrhagic stroke.
The combination of severe hypertension, flushing and sweating WITHOUT a congruent response in heart rate in the context of spinal cord injury indicates an autonomic dysreflexia and this is an important presentation to be aware of as it is one of the few unique medical emergencies that can occur to spinal cord injured patients. There is often a clear NOXIOUS STIMULUS which has triggered the episode (in this case a catheter change).
- The cause of a dysreflexia is a discontinuity between the nociceptors (pain receptor - sensory neurone) on the viscera and the brain stem autonomic centres due to the cord injury.
- All the pain receptors on smooth muscle on the abdominal and some pelvic viscera are carried by the sympathetics and the specific nerve which extends to the pelvis is the greater splanchnic nerve (which has its lowest innervation at T6 and so this is the lowest level at which autonomic dysreflexia can still occur).
Management of autonomic dysreflexia involves removal/control of the stimulus and treatment of any life-threatening hypertension and/or bradycardia.
Autonomic dysreflexia occurs when?
Autonomic dysreflexia can only occur if the spinal cord injury occurs above the T6 level
Tuberous sclerosis
Tuberous sclerosis (TS) is a genetic condition of autosomal dominant inheritance. Like neurofibromatosis, the majority of features seen in TS are NEUROCUTANEOUS
Cutaneous features:
- DEPIGMENTED ‘ash-leaf’ SPOTS which fluoresce under UV light
- roughened PATCHES of skin over LUMBAR spine (Shagreen patches)
- adenoma sebaceum (angiofibromas): BUTTERFLY distribution over nose
- fibromata beneath nails (subungual fibromata)
- café-au-lait spots may be seen
Neurological features:
- developmental delay
- epilepsy (infantile spasms or partial)
- intellectual impairment
Also:
- retinal hamartomas: dense white areas on retina (phakomata)
- rhabdomyomas of the heart
- gliomatous changes can occur in the brain lesions
- polycystic kidneys, renal angiomyolipomata
- lymphangioleiomyomatosis: multiple lung cysts
Migraine: management
Acute treatment:
- first-line: offer combination therapy with an oral TRIPTAN and an NSAID
or an oral TRIPTAN and PARACETAMOL
- not effective or not tolerated offer a non-oral preparation of metoclopramide* or prochlorperazine and consider adding a non-oral NSAID or triptan
Prophylaxis:
prophylaxis should be given if patients are experiencing 2 OR MORE ATTACKS PER MONTH.
- Either TOPIRAMATE or PROPRANOLOL
Propranolol should be used in preference to topiramate in women of child bearing age as it may be teratogenic and it can reduce the effectiveness of hormonal contraceptives
if these measures fail NICE recommend ‘a course of up to 10 sessions of acupuncture over 5-8 weeks’ or gabapentin
NICE recommend: ‘Advise people with migraine that riboflavin (400 mg once a day) may be effective in reducing migraine frequency and intensity for some people’
for women with predictable menstrual migraine treatment NICE recommend either frovatriptan (2.5 mg twice a day) or zolmitriptan (2.5 mg twice or three times a day) as a type of ‘mini-prophylaxis’
pizotifen is no longer recommend. Adverse effects such as weight gain & drowsiness are common
*caution should be exercised with young patients as acute dystonic reactions may develop
General rule of acute treatment of migraine
As a general rule 5-HT receptor agonists are used in the acute treatment of migraine whilst
5-HT receptor antagonists are used in prophylaxis.
Acute treatment of cluster headache
SUBCUTANEOUS sumatriptan + 100% O2
First line long term prevention of cluster headaches
verapamil.
Red flag symptoms and signs of trigeminal neuralgia - suggests serious underlying cause
- SENSORY changes
- DEAFNESS or other ear problems
- History of skin or oral lesions that could spread perineurally
Pain only in the ophthalmic division of the trigeminal nerve (eye socket, forehead, and nose), or bilaterally - Optic neuritis
- A family history of multiple sclerosis
- Age of onset BEFORE 40 years
Management of trigeminal neuralgia
- CARBAMAZEPINE is first-line
- failure to respond to treatment or atypical features (e.g. < 50 years old) should prompt referral to neurology
Widespread convulsions without conscious impairment…
is likely to represent a pseudoseizure
Psychogenic non-epileptic seizures- features suggesting?
(pseudoseizure)
Factors favouring pseudoseizures:
- pelvic thrusting
- family member with epilepsy
- much more common in females
- crying after seizure
- don’t occur when alone
- GRADUAL onset
- remains conscious during whole-body convulsions
- no post-ictal state
- can remember what happened
Factors favouring true epileptic seizures
- tongue biting
- raised serum prolactin*
Video telemetry is useful for differentiating
C8 radiculopathy
Reduced sensation in C8 dermatome - medial side of hand over little finger
Weakness in the C8 myotome - flex of the vital interpahalngeal and maetacarpophalangeal joints
normal elbow flexion and thumb sensation - what nerve root?
C6
sensation of middle finger
C7
Which cervical root exits BELOW the vertebrae
C8
Where does C8 exit in relation to the vertebrae?
Below the vertebrae
- is the only one that does
Parkinson’s features
Parkinson’s disease is a progressive NEURODEGENERATIVE condition caused by degeneration of dopaminergic neurons in the substantia nigra.. This results in a classic triad of features: BRADYKINESIA , TREMOR and RIGIDITY. The symptoms of Parkinson’s disease are characteristically ASYMMETRICAL.
Bradykinesia:
poverty of movement also seen, sometimes referred to as hypokinesia
short, shuffling steps with reduced arm swinging
difficulty in initiating movement
Tremor:
most marked at rest, 3-5 Hz
worse when stressed or tired, improves with voluntary movement
typically ‘pill-rolling’, i.e. in the thumb and index finger
Rigidity:
lead pipe
cogwheel: due to superimposed tremor
Other characteristic features: mask-like facies flexed posture micrographia drooling of saliva psychiatric features: depression is the most common feature (affects about 40%); dementia, psychosis and sleep disturbances may also occur impaired olfaction REM sleep behaviour disorder fatigue autonomic dysfunction: postural hypotension
DRUG-induced parkinsonism has slightly different features to Parkinson’s disease:
motor symptoms are generally RAPID onset and BILATERAL
rigidity and rest tremor are uncommon
Diagnosis is usually clinical. However, if there is difficulty differentiating between essential tremor and Parkinson’s disease NICE recommend considering 123I‑FP‑CIT single photon emission computed tomography (SPECT).
Most common complication of bacterial meningitis
Sensorineural hearing loss
Hearing tests are routinely performed to assess this
Meningitis complications
SENSORINEURAL HEARING LOSS (most common)
other neurological: epilepsy, paralysis
infective: sepsis, intracerebral abscess
pressure: brain herniation, hydrocephalus
Myasthenia Gravis pathophysiology
autoantibodies to postsynaptic nicotinic acetylcholine receptors at the neuromuscular junction
Myasthenia Gravis and anaesthesia
There are significant implications in the administration of anaesthesia, in particular muscle paralysis.
What anaesthetic drug should be avoided in those with myasthenia gravis?
SUXAMETHONIUM
Suxamethonium is a depolarising NMBD - it acts by binding to Ach receptors and activating the receptor, at first causing muscle contraction, then paralysis - as they are desensitised and stop firing.
Again, due to a decreased number of available receptors for Sux to bind to, MG patients are typically resistant to depolarising NMBDs and may require significantly higher doses.
Therefore they should be used extremely cautiously, if at all, in myasthenic patients.
Myasthenia gravis: exacerbating factors
The most common exacerbating factor is exertion resulting in FATIGABILITY, which is the hallmark feature of myasthenia gravis . Symptoms become MORE MARKED DURING THE DAY
The following drugs may exacerbate myasthenia:
penicillamine
quinidine, procainamide
beta-blockers
lithium
phenytoin
antibiotics: gentamicin, macrolides, quinolones, tetracyclines
Myasthenia Gravis
Myasthenia gravis is an autoimmune disorder resulting in INSUFFICIENT FUNCTIONING ACETYLCHOLINE RECEPTORS
Myasthenia is more common in women (2:1)
The key feature is MUSCLE FATIGABILITY - muscles become progressively weaker DURING PERIODS OF ACTIVITY and slowly improve after periods of rest:
- extraocular muscle weakness: diplopia
- PROXIMAL muscle weakness: face, neck, limb girdle
- ptosis
- dysphagia
Associations
THYMOMAS in 15%
autoimmune disorders: pernicious anaemia, autoimmune thyroid disorders, rheumatoid, SLE
thymic hyperplasia in 50-70%
Investigations
- single fibre electromyography: high sensitivity (92-100%)
- CT thorax to exclude thymoma
- CK normal
- autoantibodies: around 85-90% of patients have antibodies to acetylcholine receptors. In the remaining patients, about about 40% are positive for anti-muscle-specific tyrosine kinase antibodies
- Tensilon test: IV edrophonium reduces muscle weakness temporarily - not commonly used anymore due to the risk of cardiac arrhythmia
Management - long-acting ANTICHOLINESTERASE INHIBITORS inhibitors e.g. PYRIDOSTIGMINE immunosuppression: - prednisolone initially - thymectomy
Third nerve palsy features
Features:
- eye is deviated ‘DOWN AND OUT’
- PTOSIS
- pupil may be DILATED (sometimes called a ‘surgical’ third nerve palsy)
Causes of third nerve palsy
Causes:
- diabetes mellitus
- vasculitis e.g. temporal arteritis, SLE
- false localizing sign* due to uncal herniation through tentorium if raised ICP
- posterior communicating artery aneurysm
- pupil dilated
- often associated pain - cavernous sinus thrombosis
- Weber’s syndrome: ipsilateral third nerve palsy with contralateral hemiplegia -caused by midbrain strokes
- other possible causes: amyloid, multiple sclerosis
*this term is usually associated with sixth nerve palsies but it may be used for a variety of neurological presentations
What supplementation is indicated in Parkinson’s?
Vitamin D
Essential tremor
autosomal dominant condition which usually affects both upper limbs
Features
- postural tremor (associated with a tremor present with sustained muscle tone): worse if arms outstretched
- improved by alcohol and rest
- most common cause of titubation (head tremor)
- it can also affect the vocal cords
Management
- PROPANOLOL is first-line
- primidone is sometimes used
Peripheral neuropathy
Peripheral neuropathy may be divided into conditions which predominately cause a motor or sensory loss
Peripheral neuropathy - Predominately motor loss
Guillain-Barre syndrome
porphyria
lead poisoning
hereditary sensorimotor neuropathies (HSMN) - Charcot-Marie-Tooth
chronic inflammatory demyelinating polyneuropathy (CIDP)
diphtheria
Peripheral neuropathy - Predominately sensory loss
diabetes uraemia leprosy alcoholism vitamin B12 deficiency amyloidosis
Alcoholic neuropathy
- secondary to both direct toxic effects and reduced absorption of B vitamins
- sensory symptoms typically present prior to motor symptoms
Vitamin B12 deficiency - neurological symptoms
- subacute combined degeneration of spinal cord
- dorsal column usually affected first (joint position, vibration) prior to distal paraesthesia
Facial nerve supplies…
‘face, ear, taste, tear’
- face: muscles of facial expression
- ear: nerve to stapedius
- taste: supplies anterior two-thirds of tongue
- tear: parasympathetic fibres to lacrimal glands, also salivary glands
Causes of bilateral facial nerve palsy
- sarcoidosis
- Guillain-Barre syndrome
- Lyme disease
- bilateral acoustic neuromas (as in neurofibromatosis type 2)
- as Bell’s palsy is relatively common it accounts for up to 25% of cases of bilateral palsy, but this represents only 1% of total Bell’s palsy cases
Causes of unilateral facial nerve palsy
Lower motor neuron:
- Bell’s palsy
- Ramsay-Hunt syndrome (due to herpes zoster)
- acoustic neuroma
- parotid tumours
- HIV
- multiple sclerosis (may also cause UMN palsy)
- diabetes mellitus
Upper motor neuron
- stroke
LMN vs. UMN
face
upper motor neuron lesion ‘spares’ upper face i.e. forehead
lower motor neuron lesion affects all facial muscles
Branches of the facial nerve
3 branches:
- greater petrosal nerve
- nerve to stapedius
- chorda tympani
Intracranial venous thrombosis- features, causes and more
Overview
can cause cerebral infarction, much lesson common than arterial causes
50% of patients have isolated sagittal sinus thromboses - the remainder have coexistent lateral sinus thromboses and cavernous sinus thromboses
Features
headache (may be sudden onset)
nausea & vomiting
Sagittal sinus thrombosis
may present with seizures and hemiplegia
parasagittal biparietal or bifrontal haemorrhagic infarctions are sometimes seen
Cavernous sinus thrombosis
other causes of cavernous sinus syndrome: local infection (e.g. sinusitis), neoplasia, trauma
periorbital oedema
ophthalmoplegia: 6th nerve damage typically occurs before 3rd & 4th
trigeminal nerve involvement may lead to hyperaesthesia of upper face and eye pain
central retinal vein thrombosis
Lateral sinus thrombosis
6th and 7th cranial nerve palsies
What will lesions of T1 cause?
Causes finger abduction weakness
It affects thumb adduction and finger abduction) and a loss of sensation over the medial epicondyle
results in is Klumpke’s paralysis.
Klumpke’s paralysis
damage to T1
loss of intrinsic hand muscles
due to traction
Definition of an ataxic gait
A WIDE-based gait with loss of heel to toe walking
Causes of ataxic gait
Typically occur following cerebellar injury, the causes can be remembered by the mnemonic ‘pastries’
P - Posterior fossa tumour A - Alcohol S - Multiple sclerosis T - Trauma R - Rare causes I - Inherited (e.g. Friedreich's ataxia) E - Epilepsy treatments S - Stroke
Management of bell’s palsy
Prednisolone
Eye care - artificial tears and eye lubricants
Common reflexes
Ankle S1-S2
Knee L3-L4
Biceps C5-C6
Triceps C7-C8
Syringomyelia
Presents with CAPE-like LOSS of PAIN and TEMPERATURE due to COMPRESSION of the SPINOTHALAMIC tract fibres decussating in the anterior white commissure of the spine
Syringomyelia
Syringomyelia is a condition whereby fluid filled cavities develop within the spinal cord. Pressure can increase resulting in compression of the spinal cord tracts.
(The syrinx can extend to and damage the anterior horn cells, thereby resulting in lower motor neurone features. The spinothalamic tract axons decussate to the other side of the spinal cord via the anterior white commissure, and they are particularly susceptible to damage from the syrinx. Pain and temperature sensation are lost due to spinothalamic tract damage, and one side may be affected more than the other. Classically, the sensation loss is experienced in a shawl-like distribution over the arms, shoulders and upper body. Light touch, vibration and proprioception may also be affected as the syrinx enlarges into the dorsal columns.)
Causes include:
- a Chiari malformation: strong association
- trauma
- tumours
- idiopathic
The classical presentation of a syrinx is a patient who has a ‘CAPE-like’ (neck and arms) loss of SENSATION to but preservation of light touch, proprioception and vibration.
Classic examples are of patients who accidentally burn their hands without realising.
This is due to the crossing spinothalamic tracts in the ANTERIOR COMMISSURE of the spinal cord being the first tracts to be affected.
Other symptoms and signs include SPASTIC WEAKNESS (predominantly of the upper limbs), paraesthesia, neuropathic pain, UPGOING PLANTARS and bowel and bladder dysfunction.
Scoliosis will occur over a matter of years if the syrinx is not treated. It may cause a Horner’s syndrome due to compression of the sympathetic chain, but this is rare.
Investigation requires a full SPINE MRI with contrast to exclude a tumour or tethered cord. A brain MRI is also needed to exclude a Chiari malformation.
Treatment will be directed at treating the cause of the syrinx. In patients with a persistent or symptomatic syrinx, a shunt into the syrinx can be placed.
Wernicke’s encephalopathy
Wernicke’s encephalopathy is a neuropsychiatric disorder caused by THIAMINE DEFICIENCY which is most commonly seen in ALCOHOLICS.
Rarer causes include: persistent vomiting, stomach cancer, dietary deficiency.
A classic triad of ophthalmoplegia/nystagmus, ataxia and confusion may occur.
In Wernicke’s encephalopathy petechial haemorrhages occur in a variety of structures in the brain including the mamillary bodies and ventricle walls
Features
- nystagmus (the most common ocular sign)
- ophthalmoplegia
- ataxia
- confusion, altered GCS
- peripheral sensory neuropathy
Investigations
- decreased red cell transketolase
- MRI
Treatment is with urgent REPLACEMENT OF THIAMINE
What can happen if Wernicke’s encephalopathy is untreated.?
Korsakoff’s syndrome may develop as well.
This is termed Wernicke-Korsakoff syndrome and is characterised by the addition of antero- and retrograde AMNESIA and CONFABULATION in addition to the symptoms of Wernicke’s (nystagmus, opthalmoplegis,ataxia)
Arnold-Chiari malformation
Arnold-Chiari malformation describes the downward displacement, or HERNIATION, of the CEREBELLAR TONSILS through the FORAMEN MAGNUM. Malformations may be congenital or acquired through trauma.
Features
- non-communicating hydrocephalus may develop as a result of obstruction of cerebrospinal fluid (CSF) outflow
- headache
- syringomyelia
Charcot-maire-tooth disease - what it affects?
Can affect both MOTOR and SENSORY PERIPHERAL nerves
Duchenne muscular dystrophy
Inherited myopathy.
It is caused by progressive degeneration and weakness of SPECIFIC MUSCLE GROUPS.
- Most patients lose the ability to walk by 12 years of age and require ventilatory support by the age of 25.
- Sensation is intact in these patients.
Cervical spondylosis
Term used for OSTEOARTHRITIS of the SPINE and can result in COMPRESSION of the SPINAL CORD.
This is more likely to result in LMN signs at the level of the compression (ie. upper limb if the lesion is below C5) with UMN signs below (in the lower limb).
Patients usually complain of neck pain and stiffness.
Subacute combined degeneration of the cord -summary
- Ataxic Gait - due to degeneration of the dorsal columns
- Mixed UMN and LMN signs - due to degeneration of lateral motor tracts and peripheral nerves
- Subacute history - occurs over months
- Often notice sensory symptoms before weakness
Hereditary sensorimotor neuropathy (HSMN)
Term which encompasses Charcot-Marie-Tooth disease (also known as peroneal muscular atrophy).
HSMN type I: primarily due to demyelinating pathology - features
- autosomal dominant
- due to defect in PMP-22 gene (which codes for myelin)
- features often start at puberty
- motor symptoms predominate
- distal muscle wasting, pes cavus, clawed toes
- foot drop, leg weakness often first features
Multiple system atrophy vs Parkinson’s
UNILATERAL Parkinsonism + severe AUTONOMIC DISTURBANCE (postural hypotension/erectile dysfunction).
- more likely to be multiple system atrophy than Parkinson’s disease
Progressive supranuclear palsy has…
The presence of ocular pathology
Pabrinex
contains vitamins B and C.
It does not vitamin D.
Vitamin B1
Vitamin B1, also called thiamine, is essential for GLIAL cells of the nervous system, as well as other bodily systems.
Deficiency can cause Wernicke’s encephalopathy and if left untreated can lead to irreversible Korsakoff’s syndrome.
Vitamin B1 AKA…
Thiamine
Vitamin B12 deficiency is linked to…
Pernicious anaemia
What disease has adenoma sebaceum?
Tuberous sclerosis
Adenoma sebaceum is a butterfly distribution over nose
Lhermitte’s sign
Indicates disease near the dorsal column nuclei of the cervical cord.
It is seen in MS, subacute combined degeneration of the cord and in cervical stenosis
It is:
- paraesthesiae in limbs on neck flexion
Cauda equina
Results from COMPRESSION of the CAUDA EQUINA and classically includes:
- leg weakness
- saddle anaesthesia
- sphincter disturbance
Usually ACUTE syndrome with progressive signs.
(does not cause leg stiffness)
Degenerative cervical myelopathy- symptoms, treatment
Degenerative cervical myelopathy (DCM) has a number of risk factors, which include smoking due to its effects on the intervertebral discs, genetics and occupation - those exposing patients to high axial loading.
The presentation of DCM is very variable. Early symptoms are often subtle and can vary in severity day to day, making the disease difficult to detect initially. However as a progressive condition, worsening, deteriorating or new symptoms should be a warning sign.
DCM symptoms can include any combination of:
- Pain (affecting the neck, upper or lower limbs)
- Loss of motor function (loss of digital dexterity, preventing simple tasks such as holding a fork or doing up their shirt buttons, arm or leg weakness/stiffness leading to impaired gait and imbalance
- Loss of sensory function causing numbness
- Loss of autonomic function (urinary or faecal incontinence and/or impotence) - these can occur and do not necessarily suggest cauda equina syndrome in the absence of other hallmarks of that condition
- HOFFMAN’S sign: is a reflex test to assess for cervical myelopathy. It is performed by gently flicking one finger on a patient’s hand. A positive test results in reflex twitching of the other fingers on the same hand in response to the flick.
The most common symptoms at presentation of DCM are unknown, but in one series 50% of patients were initially incorrectly diagnosed and sometimes treated for carpal tunnel syndrome.
An MRI of the cervical spine is the gold standard test where cervical myelopathy is suspected. It may reveal disc degeneration and ligament hypertrophy, with accompanying cord signal change.
All patients with degenerative cervical myelopathy should be urgently referred for assessment by SPECIALIST SPINAL SERVICES (neurosurgery or orthopaedic spinal surgery). This is due to the importance of early treatment. The timing of surgery is important, as any existing spinal cord damage can be permanent. Early treatment (within 6 months of diagnosis) offers the best chance of a full recovery but at present, most patients are presenting too late.
Currently, DECOMPRESSIVE SURGERY surgery is the only effective treatment. It has been shown to prevent disease progression. Close observation is an option for mild stable disease, but anything progressive or more severe requires surgery to prevent further deterioration. Physiotherapy should only be initiated by specialist services, as manipulation can cause more spinal cord damage.
Diagnostic criteria for migraine without aura:
A - At least 5 attacks fulfilling criteria B-D
B - Headache attacks lasting 4-72 hours (untreated or unsuccessfully treated)
C - Headache has at least two of the following characteristics:
- unilateral location
- pulsating quality (i.e., varying with the heartbeat)
- moderate or severe pain intensity
- aggravation by or causing avoidance of routine physical activity (e.g., walking or climbing stairs)
D - During headache at least one of the following:
- nausea and/or vomiting*
- photophobia and phonophobia
E - Not attributed to another disorder (history and examination do not suggest a secondary headache disorder or, if they do, it is ruled out by appropriate investigations or headache attacks do not occur for the first time in close temporal relation to the other disorder)
Why does a high stepping gait develop…
to compensate for a foot drop
Unilateral foot drop
common peroneal nerve lesion should be suspected
Bilateral foot drop
due to peripheral neuropathy.
Why does a high stepping gait develop…
to compensate for a foot drop
Unilateral foot drop
common peroneal nerve lesion should be suspected
Bilateral foot drop
due to peripheral neuropathy.
DVLA - epilepsy
All patient must not drive and must inform the DVLA
- first unprovoked/isolated seizure: 6 months off if there are no relevant structural abnormalities on brain imaging and no definite epileptiform activity on EEG. If these conditions are not met then this is increased to 12 months
- for patients with established epilepsy or those with multiple unprovoked seizures:
→ may qualify for a driving licence if they have been free from any seizure for 12 months
→ if there have been no seizures for 5 years (with medication if necessary) a ’til 70 licence is usually restored
withdrawawl of epilepsy medication: should not drive whilst anti-epilepsy medication is being withdrawn and for 6 months after the last dose
DVLA - syncope
- simple faint: no restriction
- single episode, explained and treated: 4 weeks off
- single episode, unexplained: 6 months off
- two or more episodes: 12 months off
Parkinsonism with associated autonomic disturbance, suspect what disease?
Multiple system atrophy
Lewy body dementia presents…
Parkinsonism and visual hallucinations
Progressive supranuclear palsy presents with…
Parkinsonism and ophthalmoplegia
A lesion in the parietal lobe leads to what type of quadranopia?
Inferior quadranopia
A lesion in the temporal lobe leads to what type of quadranopia?
Superior quadranopia
Prophylaxis for migraine
Topiramate OR
propanolol
Guillain-Barre syndrome pathogenesis
Immune mediated DEMYELINATION of the peripheral nervous system often triggered by an infection (classically Campylobacter jejuni)
Pathogenesis:
- cross reaction of antibodies with gangliosides in the peripheral nervous system
- correlation between anti-ganglioside antibody (e.g. anti-GM1) and clinical features has been demonstrated
- anti-GM1 antibodies in 25% of patients
Miller Fisher syndrome
Variant of Guillain-Barre syndrome
- associated with ophthalmoplegia, areflexia and ataxia. The eye muscles are typically affected first
- usually presents as a descending paralysis rather than ascending as seen in other forms of Guillain-Barre syndrome
- anti-GQ1b antibodies are present in 90% of cases
Guillain - Barre features
Is PROGRESSIVE WEAKNESS of all FOUR limbs. The weakness is classically ASCENDING i.e. the lower extremities are affected first, however it tends to affect proximal muscles earlier than the distal ones.
SENSORY symptoms tend to be mild (e.g. distal paraesthesia) with very few sensory signs. Some patients experience BACK PAIN in the initial stages of the illness.
Other features:
- there may be a history of gastroenteritis
- areflexia
- cranial nerve involvement e.g. diplopia
- autonomic involvement: e.g. urinary retention, diarrhoea
Less common findings
- papilloedema: thought to be secondary to reduced CSF resorption
(The classical presentation of GBS is rapid, progressive onset of muscle weakness and changes in sensation starting peripherally. Important complications to be aware of, which imply more severe disease, are bulbar symptoms (eg swallowing problems), respiratory difficulties (due to respiratory muscle weakness) and autonomic instability)
Guillain - Barre investigations
LUMBAR PUNCTURE
- rise in protein with a normal white blood cell count (albuminocytologic dissociation)
Nerve condution studies may be performed
Typical (petite mal) absence seizures
- Onset 4-8 yrs
- duration few-30 secs; no warning, quick recovery; often many per day
- EEG: 3Hz generalised, symmetrical
- sodium valproate, ethosuximide
- good prognosis: 90-95% become seizure free in adolescence
What is pheochromocytoma associated with?
Neurofibromatosis - 1
Bilateral median nerve dysfunction suggestive of…
Degenerative cervical myelopathy
Should be suspected in elderly patients presenting with limb neurology.
Sinusitis + focal neurology and fever →…
?brain abscess
complication of sinusitis
Cavernous sinus thrombosis
usually presents with:
- unilateral facial oedema,
- photophobia
- proptosis
- palsies of the cranial nerves which pass through it (III, IV, V, VI).
Brain abscess
CNS abscesses may result from a number of causes including, extension of sepsis from MIDDLE EAR or SINUSES, TRAUMA or surgery to the scalp, penetrating HEAD INJURIES and embolic events from endocarditis
- The presenting symptoms will depend upon the site of the abscess (those in critical areas e.g.motor cortex) will present earlier. Abscesses have a considerable mass effect in the brain and raised intra cranial pressure is common.
- Although FEVER, HEADACHE and FOCAL NEUROLOGY are highly suggestive of a brain abscess the absence of one or more of these does not exclude the diagnosis, fever may be absent and even if present, is usually not the swinging pyrexia seen with abscesses at other sites.
- Assessment of the patient includes imaging with CT scanning.
- Treatment is usually SURGICAL, a craniotomy is performed and the abscess cavity debrided. The abscess may reform because the head is closed following abscess drainage.
Upper limb neurological symptoms indicates….
Pathology either within the car viral spinal cord to brain.
if brain - more likely to cause unilateral problems
Patients with a GCS below 8 should be considered for …
i) review by an anaesthetist - as there is risk of an unsecured airway
ii) intubation and ventilation
GCS
Motor response:
- Obeys commands
- Localises to pain
- Withdraws from pain
- Abnormal flexion to pain (decorticate posture)
- Extending to pain
- None
Verbal response:
- Orientated
- Confused
- Words
- Sounds
- None
Eye opening:
- Spontaneous
- To speech
- To pain
- None
If a patient is NBM and has Parkinson’s… what we prescribe?
If a patient is nil by mouth and needs antiparkinsonian medication, the best option is a DOPAMINE AGONIST TRANSDERMAL PATCH , which will prevent a life-threatening dystonic (person’s muscles contract uncontrollably.) withdrawal.
Loss of corneal reflex … think?
Acoustic neuroma
Vestibular schwannoma (acoustic neuroma)
A combination of VERTIGO, HEARING LOSS, TINNITUS and an ABSENT CORNEAL REFLEX.
Features can be predicted by the affected cranial nerves:
- cranial nerve VIII: vertigo, unilateral sensorineural hearing loss, unilateral tinnitus
- cranial nerve V: absent corneal reflex
- cranial nerve VII: facial palsy
Bilateral vestibular schwannomas are seen in neurofibromatosis type 2.
Patients with a suspected vestibular schwannoma should be referred urgently to ENT. It should be noted though that the tumours are often slow growing, benign and often observed initially.
MRI of the cerebellopontine angle is the investigation of choice. Audiometry is also important as only 5% of patients will have a normal audiogram.
Management is with either surgery, radiotherapy or observation.
left homonymous hemianopia , where is lesion?
(means visual field defect to the left)
RIGHT optic tract
Cerebellar tonsillar herniation affects…
Usually affects the MEDULLA OBLONGATA and is often a terminal event in an unconscious patient resulting in asystolic cardio-respiratory arrest
Ulcal herniation can lead to…
Raised ICP can cause a third nerve palsy due to herniation
A dissociated sensory loss, that is numbness at different and unlinked sites, think…
MS
Transverse myelitis
Acute
Sensory level and upper motor neuron signs below the level affected
It can occur in patients with multiple sclerosis or Devics disease (neuromyelitis optica). These patients tend to also have features such as optic neuritis.
Common peroneal nerve lesion
The sciatic nerve divides into the tibial and common peroneal nerves. Injury often occurs at the neck of the fibula
The most characteristic feature of a common peroneal nerve lesion is FOOT DROP.
Other features include:
- WEAKNESS of foot DORSIFLEXION
- weakness of foot EVERSION
- weakness of extensor hallucis longus
- sensory loss over the dorsum of the foot and the lower lateral part of the leg
- wasting of the anterior tibial and peroneal muscles
Cavernous sinus syndrome
Most commonly caused by cavernous sinus TUMOUR
Cavernous sinus syndrome features
pain (on attempt to move eye?) ophthalmoplegia proptosis trigeminal nerve lesion (opthalmic branch) Horner's syndrome.
Contents of the cavernous sinus
Oculomotor nerve Trochlear nerve Ophthalmic nerve Maxillary nerbe Internal carotid artery (and sympathetic plexus) Abducens nerve
MRC grading
Grade 0 No muscle movement Grade 1 Trace of contraction Grade 2 Movement at the joint with gravity eliminated (e.g. raising knees when on his side) Grade 3 Movement against gravity, but not against added resistance Grade 4 Movement against an external resistance with reduced strength Grade 5 Normal strength
Neuroleptic malignant syndrome
Rare but dangerous condition seen in PATIENTS TAKING ANTIPSYCHOTIC MEDICATION.
Can also occur with atypical antipsychotics.
May also occur with dopaminergic drugs (such as levodopa) for Parkinson’s disease, usually when the drug is SUDDENLY STOPPED or DOSE REDUCED.
The pathophysiology is unknown but one theory is that the dopamine blockade induced by antipsychotics triggers massive glutamate release and subsequent neurotoxicity and muscle damage.
It occurs WITHIN HOURS TO DAYS OF STARTING AN ANTIPSYCHOTIC (antipsychotics are also known as neuroleptics, hence the name) and the typical features are:
- pyrexia
- muscle rigidity
- autonomic lability: typical features include hypertension, tachycardia and tachypnoea
- agitated delirium with confusion
A RAISED CK is present in most cases.
ACUTE KIDNEY INJURY (secondary to rhabdomyolysis) may develop in severe cases.
A LEUKOCYTOSIS may also be seen (above the average of WCC)
Management:
- stop antipsychotic
- patients should be transferred to a medical ward if they are on a psychiatric ward and often they are nursed in intensive care units
- IV fluids to prevent renal failure
- dantrolene* may be useful in selected cases
- bromocriptine, dopamine agonist, may also be used
*thought to work by decreasing excitation-contraction coupling in skeletal muscle by binding to the ryanodine receptor, and decreasing the release of calcium from the sarcoplasmic reticulum
Degenervative cervical myelopathy -leads to loss of…
FINE MOTOR function in BOTH UPPER arms
What is the Hoffman’s sign
UMN sign
REFLEX test to investigate CORTICOSPINAL TRACT LESIONS
Hoover’s sign?
Differentiates between organic and non-organic LOWER LEG weakness
Brown - Sequard syndrome
Overview:
caused by LATERAL HEMISECTION of the spinal cord
Features:
ipsilateral weakness below lesion (corticospinal tract)
ipsilateral loss of proprioception and vibration and touch sensation (dorsal column)
contralateral loss of pain and temperature sensation (spinothalamic tract)
Internuclear ophthalmoplegia
Overview:
- a cause of horizontal disconjugate eye movement
- due to a lesion in the medial longitudinal fasciculus (MLF), which connects the IIIrd, IVth and VIth cranial nuclei - a tract that allows conjugate eye movement.
Features:
- impaired ADduction of the eye on the same side as the lesion
- horizontal nystagmus of the abducting eye on the contralateral side
Causes:
- multiple sclerosis
- vascular disease
RAPD- damage to what?
RAPD is a defect in the direct response to light.
It is due to damage in OPTIC NERVE or severe retinal disease.
If an optic nerve lesion is present the affected pupil will not constrict to light when light is shone in the that pupil during the swinging flashlight test. However, it will constrict if light is shone in the other eye (consensual response).
The most likely cause for this is an OPTIC NEURITIS. Other causes include ischemic optic disease or retinal disease, severe glaucoma causing trauma to optic nerve and direct optic nerve damage (trauma, radiation, tumor).
Causes of Parkinsonism
- Parkinson’s disease
- drug-induced e.g. antipsychotics, metoclopramide
- progressive supranuclear palsy
- multiple system atrophy
- Wilson’s disease
- post-encephalitis
- dementia pugilistica (secondary to chronic head trauma e.g. boxing)
- toxins: carbon monoxide, MPTP
What is the most appropriate anti-emetic to prescribe for a patient with Parkinson’s disease?
DOMPERIDONE does not cross the blood-brain barrier and therefore does not cause extra-pyramidal side-effects.
(Cyclizine is an antihistamine which, like prochlorperazine, may exacerbate Parkinson’s disease.)
Features that are NOT in MND
- doesn’t affect external ocular muscles
- no cerebellar signs
- abdominal reflexes are usually preserved and sphincter dysfunction if present is a late feature
Xanthochromia in CSF…?
Subarachnoid haemorrhage
Sinister headache - the main 5:
- Vomiting more than once with no other cause.
- New neurological deficit (motor or sensory).
- Reduction in conscious level (as measured by the Glasgow coma score).
- Valsalva (associated with coughing or sneezing) or positional headaches.
- Progressive headache with a fever.
NICE suggest that if two or more of the ‘red-flag’ criteria are present then an urgent CT scan should be performed
Headache red flags - full list
- compromised immunity, caused, for example, by HIV or immunosuppressive drugs
- age under 20 years and a history of malignancy
- a history of malignancy known to metastasis to the brain
- vomiting without other obvious cause
- worsening headache with fever
- sudden-onset headache reaching maximum intensity within 5 minutes - ‘thunderclap’
- new-onset neurological deficit
- new-onset cognitive dysfunction
- change in personality
- impaired level of consciousness
- recent (typically within the past 3 months) head trauma
- headache triggered by cough, valsalva (trying to breathe out with nose and mouth blocked), sneeze or exercise
- orthostatic headache (headache that changes with posture)
- symptoms suggestive of giant cell arteritis or acute narrow-angle glaucoma
- a substantial change in the characteristics of their headache
What could happen if ulnar nerve is damaged?
Damage at wrist
- ‘claw hand’ - hyperextension of the metacarpophalangeal joints and flexion at the distal and proximal interphalangeal joints of the 4th and 5th digits
- wasting and paralysis of intrinsic hand muscles (except lateral two lumbricals)
- wasting and paralysis of hypothenar muscles
- sensory loss to the medial 1 1/2 fingers (palmar and dorsal aspects)
Damage at elbow
- as above (however, ulnar paradox - clawing is more severe in distal lesions)
- radial deviation of wrist
Treatment of generalised tonic- clonic seizures
sodium valproate
second line: lamotrigine, carbamazepine
Treatment for Absence seizures (Petit mal)
sodium valproate or ethosuximide
sodium valproate particularly effective if co-existent tonic-clonic seizures in primary generalised epilepsy
(NOTE: *carbamazepine may exacerbate absence seizures)
Treatment for Myoclonic seizures
sodium valproate
second line: clonazepam, lamotrigine
(NOTE: carbamazepine may exacerbate myoclonic seizures)
Treatment for focal seizures
first line: carbamazepine or lamotrigine
second line: levetiracetam, oxcarbazepine or sodium valproate
General treatment for seizures
Sodium valproate is considered the first line treatment for patients with generalised seizures with carbamazepine used for focal seizures.
MS management -acute relapse
HIGH DOSE STEROIDS (e.g. oral or IV methylprednisolone) may be given for 5 days to shorten the length of an acute relapse.
It should be noted that steroids shorten the duration of a relapse and do not alter the degree of recovery (i.e. whether a patient returns to baseline function)
MS management - DMTs
- BETA-INTERFERON has been shown to reduce the relapse rate. Certain criteria have to be met before it is used:
relapsing-remitting disease + 2 relapses in past 2 years + able to walk 100m unaided
secondary progressive disease + 2 relapses in past 2 years + able to walk 10m (aided or unaided)
reduces number of relapses and MRI changes, however doesn’t reduce overall disability
Other drugs used in the management of multiple sclerosis include:
- glatiramer acetate: immunomodulating drug - acts as an ‘immune decoy’
- natalizumab: a recombinant monoclonal antibody that antagonises Alpha-4 Beta-1-integrin found on the surface of leucocytes, thus inhibiting migration of leucocytes across the endothelium across the blood-brain barrier
- fingolimod: sphingosine 1-phosphate receptor modulator, prevents lymphocytes from leaving lymph nodes. An oral formulation is available
MS management - fatigue
once other problems (e.g. anaemia, thyroid or depression) have been excluded NICE recommend a trial of amantadine
other options include mindfulness training and CBT
MS management - spasticity
baclofen and gabapentin are first-line. Other options include diazepam, dantrolene and tizanidine
physiotherapy is important
cannabis and botox are undergoing evalulation
MS management - bladder dysfunction
- may take the form of urgency, incontinence, overflow etc
- guidelines stress the importance of getting an ultrasound first to assess bladder emptying - anticholinergics may worsen symptoms in some patients
- if significant residual volume → intermittent self-catheterisation
- if no significant residual volume → anticholinergics may improve urinary frequency
MS management - Oscillopsia (visual fields apper to oscillate)
gabapentin is first-line
Features of Arnold - Chiari malformation
- non-communicating hydrocephalus may develop as a result of obstruction of cerebrospinal fluid (CSF) outflow
- headache
- syringomyelia
Idiopathic intracranial hypertension - risk factors, features, mx
is a condition classically seen in young, overweight females.
Features: headache blurred vision papilloedema (usually present) enlarged blind spot sixth nerve palsy may be present
Risk factors: obesity female sex pregnancy drugs*: oral contraceptive pill, steroids, tetracycline antibodies, vitamin A, lithium, isotretinoin, levothyroxine, cimetidine
Management:
- weight loss
- diuretics e.g. acetazolamide
topiramate is also used, and has the added benefit of causing weight loss in most patients
- repeated lumbar puncture
- surgery: optic nerve sheath decompression and fenestration may be needed to prevent damage to the optic nerve. A lumboperitoneal or ventriculoperitoneal shunt may also be performed to reduce intracranial pressure
*if intracranial hypertension is thought to occur secondary to a known causes (e.g. Medication) then it is of course not idiopathic
Foot drop possible causes …
- L5 radiculopathy
- sciatic nerve lesion
- common peroneal nerve lesion
- superficial or deep peroneal nerve lesion
- other possible includes central nerve lesions (e.g. stroke) but other features are usually present
A common peroneal nerve lesion is the most common cause. This is often secondary to compression at the neck of the fibula. This may be caused by certain positions such as leg crossing, squatting or kneeling. Prolonged confinement, recent weight loss, Baker’s cysts and plaster casts to the lower leg are also known to be precipitating factors.
Risk factors for MS
- smoking
- previous infectious mononucleosis - glandular fever
- genetics
- hypovitaminosis D
Klumpke’s paralysis
Lesion at brachial trunks C8-T1
Classically there is weakness of the hand intrinsic muscles. Involvement of T1 may cause a Horner’s syndrome - as the nerves leave and join the sympathetic chain at T1
It occurs as a result of traction injuries or during delivery.
Erb’s palsy
Lesion at brachial trunks Brachial Trunks C5-6
Broca’s dysphasia - what would the speech be like?
speech non-fluent, COMPREHENSION NORMAL, repetition good
Does acoustic neuroma have vertigo?
Yes
Cerebral artery strokes cause aphasia… what is affected?
left middle cerebral artery
How to differentiate meningitis and encephalitis?
Cerebral function usually remains normal in a patient with meningitis while in encephalitis, however, abnormalities in brain function are a differentiating feature, including altered mental status.
What to start if patient is suspected to have encephalitis?
Aciclovir
Encephalitis
Features:
fever, headache, psychiatric symptoms, seizures, vomiting
focal features e.g. aphasia
peripheral lesions (e.g. cold sores) have no relation to presence of HSV encephalitis
Pathophysiology:
HSV-1 responsible for 95% of cases in adults
typically affects temporal and inferior frontal lobes
Investigation:
- CSF: lymphocytosis, elevated protein
- PCR for HSV
- CT: medial temporal and inferior frontal changes (e.g. petechial haemorrhages) - normal in one-third of patients
- MRI is better
- EEG pattern: lateralised periodic discharges at 2 Hz
bulbar sign of motor neuron disease?
Tongue fasciculations
triggers of migraines
CHOCOLATE
Chocolate Hangovers Orgasms Cheese Caffeine The oral contraceptive pill Lie-ins Alcohol Travel Exercise
Neuroleptic malignant syndrome often presents with… (blood results)
raised CK
Leukocytosis
Patients may have high potassium, not usually low, due to the muscle damage seen.
Where is the lesion in the brain that leads to Wernicke’s aphasia?
How would a patient present as?
superior temporal gyrus
patients being able to produce fluent speech, but comprehension and repetition is impaired.
Wernicke’s (recpetive) aphasia
Due to a lesion of the superior temporal gyrus. It is typically supplied by the inferior division of the left MCA
This area ‘forms’ the speech before ‘sending it’ to Broca’s area.
Lesions result in sentences that make NO SENSE, word substitution and neologisms but speech remains fluent
Comprehension is impaired
Broca’s (expressive) aphasia
Due to a lesion of the inferior frontal gyrus. It is 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 fasiculus - the connection between Wernicke’s and Broca’s area
Speech is fluent but repetition is poor. Aware of the errors they are making
Comprehension is normal
Global aphasia
Large lesion affecting all 3 of the above areas resulting in severe expressive and receptive aphasia
Prophylaxis for migraine
Topiramate
or
propanolol
First line treatment for neuropathic pain
Amitriptyline, Duloxetine, gabapentin or pregabalin
if the first line drug treatment doesn’t work try one of the other 3 drugs
What is used as ‘rescue therapy’ for exacerbations of neuropathic pain?
Tramadol
What may be used for LOCALISED neuropathic pain (e.g. post-herpetic neuralgia)?
Topical capsaicin
Cerebellar syndrome - symptoms, causes
Unilateral cerebellar lesions cause ipsilateral signs.
Useful and well-known mnemonic to remember symptoms of cerebellar disease is DANISH:
D - Dysdiadochokinesia, Dysmetria (past-pointing), patients may appear ‘Drunk’
A - Ataxia (limb, truncal)
N - Nystamus (horizontal = ipsilateral hemisphere)
I - Intention tremour
S - Slurred staccato speech, Scanning dysarthria
H - Hypotonia
Causes
- Friedreich’s ataxia, ataxic telangiectasia
- neoplastic: cerebellar haemangioma
- stroke
- alcohol
- multiple sclerosis
- hypothyroidism
- drugs: phenytoin, lead poisoning
- paraneoplastic e.g. secondary to lung cancer
Multiple sclerosis: features
Patient’s with multiple sclerosis (MS) may present with non-specific features, for example around 75% of patients have significant lethargy.
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 reasonable historical evidence of a previous relapse.
Visual
- optic neuritis: common presenting feature
- optic atrophy
- Uhthoff’s phenomenon: worsening of vision following rise in body temperature
- internuclear ophthalmoplegia
Sensory
- pins/needles
- numbness
- trigeminal neuralgia
- Lhermitte’s syndrome: paraesthesiae in limbs on neck flexion
Motor
- spastic weakness: most commonly seen in the legs
Cerebellar
- ataxia: more often seen during an acute relapse than as a presenting symptom
- tremor
Others
- urinary incontinence
- sexual dysfunction
- intellectual deterioration
In a Colle’s fracture, what is the nerve affected?
a Colle’s fracture, which is a fracture of the distal radius that sometimes involves the ulna. The median nerve is most commonly affected. As the median nerve supplies the motor supply for the radial half of the fingers in the hand, it explains why he has lost the ability to abduct his thumb.
Thrombolysis for acute ischaemic stroke - when given?
Thrombolysis with alteplase should only be given if:
- it is administered within 4.5 hours of onset of stroke symptoms (unless as part of a clinical trial)
- haemorrhage has been definitively excluded (i.e. Imaging has been performed)
Cerebellar syndrome - symptoms, causes
Unilateral cerebellar lesions cause ipsilateral signs.
Useful and well-known mnemonic to remember symptoms of cerebellar disease is DANISH:
D - Dysdiadochokinesia, Dysmetria (past-pointing), patients may appear ‘Drunk’
A - Ataxia (limb, truncal)
N - Nystamus (horizontal = ipsilateral hemisphere)
I - Intention tremour
S - Slurred staccato speech, Scanning dysarthria
H - Hypotonia
Causes
- Friedreich’s ataxia, ataxic telangiectasia
- neoplastic: cerebellar haemangioma
- stroke
- alcohol
- multiple sclerosis
- hypothyroidism
- drugs: phenytoin, lead poisoning
- paraneoplastic e.g. secondary to lung cancer
Multiple sclerosis: features
Patient’s with multiple sclerosis (MS) may present with non-specific features, for example around 75% of patients have significant lethargy.
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 reasonable historical evidence of a previous relapse.
Visual
- optic neuritis: common presenting feature
- optic atrophy
- Uhthoff’s phenomenon: worsening of vision following rise in body temperature
- internuclear ophthalmoplegia
Sensory
- pins/needles
- numbness
- trigeminal neuralgia
- Lhermitte’s syndrome: paraesthesiae in limbs on neck flexion
Motor
- spastic weakness: most commonly seen in the legs
Cerebellar
- ataxia: more often seen during an acute relapse than as a presenting symptom
- tremor
Others
- urinary incontinence
- sexual dysfunction
- intellectual deterioration
In a Colle’s fracture, what is the nerve affected?
a Colle’s fracture, which is a fracture of the distal radius that sometimes involves the ulna. The median nerve is most commonly affected. As the median nerve supplies the motor supply for the radial half of the fingers in the hand, it explains why he has lost the ability to abduct his thumb.
Thrombolysis for acute ischaemic stroke - when given?
Thrombolysis with alteplase should only be given if:
- it is administered within 4.5 hours of onset of stroke symptoms (unless as part of a clinical trial)
- haemorrhage has been definitively excluded (i.e. Imaging has been performed)
Progressive peripheral polyneuropathy with hyporeflexia suggests…
Guillain–Barré syndrome (GBS)
typical triad of Wernicke’s encephalopathy…
confusion, ataxia, ophthalmoplegia
This is thought to be due to a deficiency in thiamine and often seen in alcoholics.
What medication can be given for idiopathic inter cranial hypertension
Acetazolamide
Causes of postural hypotension ? with comepensatory tachycardia
The ‘4Ds’ can be useful in remembering causes of postural hypotension with compensatory tachycardia.
- Deconditioning.
- Dysfunctional heart: aortic stenosis.
- Dehydration: disease (acute illness, adrenal insufficiency), dialysis, drugs (diuretics, narcotics).
- Drugs: anti-anginals, anti-parkinsonian medications (levodopa), antidepressants, antipsychotics, anti–benign prostatic hyperplasia drugs (tamsulosin).
Parkinson’s can lead to postural hypotension due to autonomic failure, but no compensatory tachycardia on standing.
Tremor in Parksinsons
The tremor seen in Parkinson’s disease is often asymmetric , occurs with rest, and improves with voluntary activity
What medication is shown to have a survival benefit for MND?
Riluzole
- prevents stimulation of glutamate receptors
- used mainly in amyotrophic lateral sclerosis
- prolongs life by about 3 months
In Guillain - Barre syndrome - sensory features ?
sensory symptoms tend to be mild (e.g. distal paraesthesia) with very few sensory signs
(or none)
Motor neuron disease is associated - features on motor conduction and nerve conduction studies?
NORMAL motor conduction on nerve conduction studies
Post -ictal weakness is seen when?
In patients with focal seizures
A focal weakness, typically of the frontal lobe (motor strip), may occur following a focal-onset seizure - this is called Todd’s paresis.
What can provoke an absence seizure?
seizures may be provoked by hyperventilation or stress
Absence seizures - features , management
Absence seizures (petit mal) are a form of generalised epilepsy that is mostly seen in children. The typical age of onset of 3-10 years old and girls are affected twice as commonly as boys
Features
- absences last a few seconds and are associated with a quick recovery
- seizures may be provoked by hyperventilation or stress
- the child is usually unaware of the seizure
- they may occur many times a day
- EEG: bilateral, symmetrical 3Hz spike and wave pattern
Management
- sodium valproate and ethosuximide are first-line treatment
- good prognosis - 90-95% become seizure free in adolescence
Migraine and the combined oral contraceptive (COC) pill
if patients have migraine with aura then the COC is absolutely contraindicated due to an increased risk of stroke
Bell’s palsy is more common in whom?
Pregnant women
C7 dermatome
middle finger +palm of hand
What type of palsy is Bell’s palsy?
lower motor neurone facial nerve palsy
the movement of the forehead/ eyebrow-raising is therefore affected
Classic features of normal pressure hydrocephalus
A classical triad of features is seen
- urinary incontinence
- dementia and bradyphrenia
- gait abnormality (may be similar to Parkinson’s disease)
It is thought around 60% of patients will have all 3 features at the time of diagnosis. Symptoms typically develop over a few months.
Normal pressure hydrocephalus- overview, imaging, mx
Normal pressure hydrocephalus is a reversible cause of dementia seen in elderly patients. It is thought to be secondary to reduced CSF absorption at the arachnoid villi. These changes may be secondary to head injury, subarachnoid haemorrhage or meningitis.
Imaging
- hydrocephalus with an enlarged fourth ventricle
- in addition to the ventriculomegaly there is typically an absence of substantial sulcal atrophy
Management
- ventriculoperitoneal shunting
- around 10% of patients who have shunts experience significant complications such as seizures, infection and intracerebral haemorrhages
Lambert-Eaton syndrome - associated with what?
Association with small cell lung cancer and to a lesser extent breast and ovarian cancer.
Lambert - Eaton syndrome
Lambert-Eaton myasthenic syndrome is seen in association with small cell lung cancer and to a lesser extent breast and ovarian cancer. It may also occur independently as an autoimmune disorder. Lambert-Eaton myasthenic syndrome is caused by an antibody directed against presynaptic voltage-gated calcium channel in the peripheral nervous system.
Features:
- repeated muscle contractions lead to increased muscle strength (in contrast to myasthenia gravis)
- -in reality, this is seen in only 50% of patients and following prolonged muscle use muscle strength will eventually decrease
- limb-girdle weakness (affects lower limbs first)- ( can manifest as a waddling gait)
- hyporeflexia
- autonomic symptoms: dry mouth, impotence, difficulty micturating
- ophthalmoplegia and ptosis not commonly a feature (unlike in myasthenia gravis)
EMG
incremental response to repetitive electrical stimulation
Management
treatment of underlying cancer
immunosuppression, for example with prednisolone and/or azathioprine
3,4-diaminopyridine is currently being trialled
works by blocking potassium channel efflux in the nerve terminal so that the action potential duration is increased. Calcium channels can then be open for a longer time and allow greater acetylcholine release to the stimulate muscle at the end plate
intravenous immunoglobulin therapy and plasma exchange may be beneficial
What is the main treatment for Degenerative cervical myelopathy?
Decompressive surgery
should be by specialist spinal services (neurosurgery or orthopaedic spinal surgery).
Main features of neuroleptic malignant syndrome?
Seen in patients taking antipsychotic medication
hyperthermia
muscle rigidity
autonomic instability
altered mental status
Fourth nerve palsy- overview, features
Overview
- supplies superior oblique (depresses eye, moves inward)
Features
- vertical diplopia
- -classically noticed when reading a book or going downstairs
- subjective tilting of objects (torsional diplopia)
- the patient may develop a head tilt, which they may or may not be aware of
- when looking straight ahead, the affected eye appears to deviate upwards and is rotated outwards
What type of lesion causes gait ataxia?
Cerebellar VERMIS lesions cause gait ataxia
Cerebellar HEMISPHERE lesions cause peripheral (‘finger-nose ataxia’)
Lesion of what nerve causes weakness of foot dorsiflexion and foot eversion?
Common peroneal nerve lesion
Subarachnoid haemorrhage- fetaures
Sudden onset severe OCCIPITAL headache , like being ‘kicked in the back of the head’
The pain is worse when bends neck.
Gold standard test where cervical myelopathy is suspected
MRI of the cervical spine
What management to undertaken after one has a their first suspected epileptic seizure?
- Refer to epilepsy clinic only
Anti-epileptic drug treatment should only be started before specialist review in exceptional circumstances including:
- Seizure activity observed on EEG
- Presence of a neurological deficit
- Presence of a structural brain abnormality
- Patient, parent or carer considers the risk of a further seizure to be unacceptable
Recent diagnosis of Parkinsonism with associated autonomic disturbance (atonic bladder, postural hypotension) .. ??
More likely due to multisystem atrophy rather than idiopathic Parkinson’s.
Idiopathic Parkinsons disease can cause autonomic instability, but this is usually a very late development. If it rapidly follows a diagnosis of Parkinson’s disease (for example, two weeks, as in the question), it is more likely due to multisystem atrophy rather than idiopathic Parkinson’s. 5% of patients with idiopathic Parkinson’s disease have postural hypotension, compared to 75% of patients with multisystem atrophy, making the latter more likely.
What condition is associated with bilateral vestibular schwannomas?
Neurofibromatosis type 2
vestibular schwannomas (previously known as acoustic neuromas
How to diagnose a carotid artery stenosis? What would be found on examination?
duplex ultrasound
Would hear a carotid bruit
Meningiomas ?
typically benign tumours that develop from the dura mater of the meninges
They are extra-axial lesions, meaning they do not arise from the brain parenchyma. They do not invade the brain substance, but rather cause symptoms by compression.
Restless legs syndrome - clinical features, causes and associations , mx
Restless legs syndrome (RLS) is a syndrome of spontaneous, continuous lower limb movements that may be associated with paraesthesia. It is extremely common, affecting between 2-10% of the general population. Males and females are equally affected and a family history may be present
Clinical features
- uncontrollable urge to move legs (akathisia). Symptoms initially occur at night but as condition progresses may occur during the day. Symptoms are worse at rest
- paraesthesias e.g. ‘crawling’ or ‘throbbing’ sensations
- movements during sleep may be noted by the partner - periodic limb movements of sleeps (PLMS)
Causes and associations
- there is a positive family history in 50% of patients with idiopathic RLS
- iron deficiency anaemia
- uraemia
- diabetes mellitus
- pregnancy
The diagnosis is clinical although bloods such as ferritin to exclude iron deficiency anaemia may be appropriate
Management
- simple measures: walking, stretching, massaging affected limbs
- treat any iron deficiency
- dopamine agonists are first-line treatment (e.g. Pramipexole, ropinirole)
- benzodiazepines
- gabapentin
What can cause bitemporal hemianopia?
pituitary tumour- lower quadrant defect
craniopharyngioma- upper quadrant defect
What is Cataplexy?
Cataplexy describes the sudden and transient loss of muscular tone caused by strong emotion (e.g. laughter, being frightened). Around two-thirds of patients with narcolepsy have cataplexy.
Features range from buckling knees to collaps
Does weakness improve or get worse with exercise in Myasthenia Gravis?
worsens after exercise
Weakness in Lambert Eaton improves after exercise
What antibodies are accosted with Myasthenia Gravis?
ACh receptor antibodies
Nutrition - Refeeding syndrome- the metabolic consequences, high risk f, prescription
Refeeding syndrome describes the metabolic abnormalities which occur on feeding a person following a period of starvation. The metabolic consequences include: Hypophosphataemia Hypokalaemia Hypomagnesaemia Abnormal fluid balance
These abnormalities can lead to organ failure.
High risk for re-feeding problems
If one or more of the following:
- BMI < 16 kg/m2
- Unintentional weight loss >15% over 3-6 months
- Little nutritional intake > 10 days
- Hypokalaemia, Hypophosphataemia or hypomagnesaemia prior to feeding (unless high)
If two or more of the following:
BMI < 18.5 kg/m2
- Unintentional weight loss > 10% over 3-6 months
- Little nutritional intake > 5 days
- History of: alcohol abuse, drug therapy including insulin, chemotherapy, diuretics and antacids
Prescription
- Start at up to 10 kcal/kg/day increasing to full needs over 4-7 days
- Start immediately before and during feeding: oral thiamine 200-300mg/day, vitamin B co strong 1 tds and supplements
- Give K+ (2-4 mmol/kg/day), phosphate (0.3-0.6 mmol/kg/day), magnesium (0.2-0.4 mmol/kg/day)
What is used for long term prevention of cluster headaches?
Verapamil
Sumatriptan is used as an ACUTE rescue therapy (along with high-flow oxygen)
An isolated result of high protein in the CSF is indicative of …
Guillain Barre Syndrome
Pontine haemorrhage - when does it occur? How they present?
It often occurs as a complication secondary to chronic hypertension. Patients often present with reduces Glasgow coma score, quadriplegia, miosis, and absent horizontal eye movements.
What blood test can be used to differentiate between a true seizure and a pseudoseizure?
Prolactin - in psuedoseizures
Elevated serum prolactin 10 to 20 minutes after an episode can be used to differentiate a general tonic-clonic/partial seizure from a non-epileptic pseudo seizure.
What nerve is affected in a fracture of the shaft of the humerus?
radial nerve
What is the best assessment tool for differentiating between stroke and stroke mimics?
The Recognition of Stroke in the Emergency Room (ROSIER) scale is effective in the initial differentiation of acute stroke from stroke mimics.
The National Institutes of Health Stroke Scale (NIHSS) is a tool used to …
objectively measure the impairment caused by a stroke.
What are Jacksonian movement - what does it indicate?
Jacksonian movement (clonic movements travelling proximally)
Indicates frontal lobe epilepsy
Syringomyelia - causes what type of loss?
spinothalamic sensory loss (pain and temperature)
If one has painful third nerve palsy - important to exclude…?
posterior communicating artery aneurysm
What is the The Barthel index?
Measures disability or dependence in 10 different activities of daily living in stroke patients. This index can be used to assess the functional status and to monitor their improvement with ongoing rehabilitation.
A useful mnemonic to remember the features of Wernicke’s encephalopathy is..
CAN OPEN
Confusion Ataxia Nystagmus Ophthalmoplegia PEripheral Neuropathy
Management of myasthenic crisis
- plasmapheresis - filter blood
- intravenous immunoglobulins
A recognised adverse effect of lamotrigine therapy is
Stevens-Johnson syndrome
what seizures have tend to have a gradual onset
Pseudoseizures
Ptosis +constricted pupil =
Horner’s
Ptosis + dilated pupil =
third nerve palsy
Straight leg raise- what is this associated with?
Radicular pathology such as disc herniation. The patient feels pain in the back when the leg is raised between 30-60 degrees.
What are the main features of neuroleptic malignant syndrome?
4 features
- rigidity
- hyperthermia
- autonomic instability (hypotension, tachycardia)
- altered mental status (confusion)
Other than antipsychotics - what can cause neuroleptic malignant syndrome?
Acute withdrawal of LEVODOPA can precipitate neuroleptic malignant syndrome
As a result, levodopa is a critical medication, and must be given on time and not missed with acute admissions.
Giving METOCLOPAMIDE or HALOPERIDOL, rather than withholding them, can precipitate neuroleptic malignant syndrome due to their dopaminergic antagonism.
Post lumbar puncture headache?
Headache following lumbar puncture (LP) occurs in approximately one-third of patients. The pathophysiology of is unclear but may relate to a ‘leak’ of CSF following dural puncture. Post-LP headaches are more common in young females with a low body mass index
Typical features
- usually develops within 24-48 hours following LP but may occur up to one week later
- may last several days
- worsens with upright position
- improves with recumbent position
Factors which may contribute to headache
- Increased needle size
- Direction of bevel
- Not replacing the stylet
- Increased number of LP attempts
Factors which do not contribute to headache
- Increased volume of CSF removed
- Bed rest following procedure
- Increased fluid intake post procedure
- Opening pressure of CSF
- Position of patient
Management:
- supportive initially (analgesia, rest)
- if pain continues for more than 72 hours then specific
- treatment is indicated, to prevent subdural haematoma
treatment options include: blood patch, epidural saline and intravenous caffeine
Paediatric status epilepticus- management - stepwise ?
- Buccal midazolam/ IV lorazepam
- IV lorazepam
- IV phenytoin (phenobarbital if already on regular phenytoin)
- Rapid sequence induction of anaesthesia using thiopental sodium
What lesion can cause weakness of foot dorsiflexion and foot eversion?
Common peroneal nerve lesion
What is the Cushing’s reflex?
a physiological nervous system response to increased intracranial pressure (ICP) that results in hypertension and bradycardia
The mechanism of injury, loss of consciousness and ‘lucid interval’ indicates…
extradural haematoma
Unilateral spastic paresis and loss of proprioception/vibration sensation with loss of pain and temperature sensation on the opposite side. indicates?
Brown- Séquard Syndrome
Seizures: acute management- doses?
BNF recommend dose for rectal diazepam, repeated once after 10-15 minutes if necessary
BNF recommend dose for rectal diazepam, repeated once after 10-15 minutes if necessary
Neonate 1.25 - 2.5 mg Child 1 month - 1 year 5 mg Child 2 years - 11 years 5 - 10 mg Child 12 years - 17 years 10 mg Adult 10 - 20 mg (max. 30 mg) Elderly 10 mg (max. 15 mg)
