Neurology Flashcards
What is epilepsy?
(a) 2 unprovoked seizures occurring >24hrs within each other.
Or
(b) 1 unprovoked seizure where the recurrence probability within 10yrs is same as recurrence rate of (a).
Or
(c) diagnosed with epilepsy syndrome.
A seizure is a single event in time whereas epilepsy is the tendency to have multiple seizures.
What are the RF for developing epilepsy?
Mainly unknown Premature birth Dementia/neurodegenerative disorders Head trauma/infection FHx Cerebral malformation Co morbid conditions- common with older people (stroke, cerebrovascular disease) Vascular Infection Trauma Tumour
What are the causes/triggers of seizures?
Cerebral tumours Intracranial infections Head injury Illicit drugs Alcohol (acute intoxication/withdrawal) Hypoxia Stroke Low Na, Ca and Mg
What should be asked about in an epilepsy history?
Presence of triggers?
Before the attack- any aura?
Attack- short lived? Sudden muscle tone loss? Any generalised stiffening, rhythmic jerking of limbs, urinary incontinence, tongue biting? Any behavioural arrest? Any brief shock like jerks?
After attack- Any post ictal phenomena? (Have some remaining symptoms I.e. amnesia, headache, drowsiness).
How would a suspected seizure be investigated?
Physical examination-
Oral mucosa- Any signs of lateral tongue biting?
Any injuries sustained during the attack?
Cardiac, mental state, neuro and maybe developmental assessment.
Baseline tests including FBC, U+Es, LFTs, Ca and glucose.
12 lead ECG.
What are the different types of seizures?
Generalised tonic-clonic seizures
Focal
Myoclonic
Absence
What is a generalised tonic-clonic seizure?
Tonic:
First phase where there is a loss of consciousness and the Px may fall. Strong spasms of muscles forcing air out of the lungs, cry/moan.
Can have foam/saliva from the mouth, tongue biting and impaired breathing due to stiffness.
Clonic:
Jerking movement of face, arms, legs becoming rapid and intense.
After 1-2 mins slows down and body relaxes, including bladder and bowel.
Px lets out deep sigh and normal breathing is restored.
Post ictal phase:
Px can remain unconscious for a few minutes until the brain recovers.
Regains awareness, may be exhausted/confused/sore for few hrs.
May have post ictal amnesia.
What is a focal seizure?
Complex partial seizure. Lasting 30 seconds to 1 minute. Aura may occur as a warning (visual, auditory, olfactory, fright, unfamiliarity to a place etc) Lip smirking Hand at the chest Stop behaviour momentarily
What is a myoclonic seizure?
Sudden, brief involuntary muscle jerks (similar to when everyone foot jerks in bed).
May be mild, affecting one part of the body.
May be strong enough to throw a person on the floor.
More clear in extreme scenarios I.e. Px falling down or car accident.
What is an absence seizure?
Common in children, most grow out in teenage years.
Momentary loss of awareness.
Looks like a vacant/blank stare.
Lasting less than 30 seconds, occurring a few times a day.
Eyes turn upwards and eyelids flutter
Don’t realise they have had the seizure and carry on where they left off.
How is the first seizure in epilepsy managed?
Needs immediate specialist referral
Advise to stop driving until seen specialist
Advise Px and family of possible epilepsy diagnosis
Advise on triggers of seizures i.e. alcohol, sleep deprivation etc
Advise witness of seizure to attend with the Px to see the specialist.
Discharge with outpatient MRI and baseline EEG.
How is a generalised tonic-clonic seizure managed?
Same management for unclassifiable seizures
Px is woman of child bearing potential;
First line AED- Lamotrigine
Alternatives- Levatiracetum, Valporate
Px is not a woman of child bearing potential;
First line AED- Valporate
Alternatives- Lamotrigine, Levatiracetum
How is a focal seizure managed?
First line AED- Carbamazepine
Alternatives- Lamotrigine, Levatiracetum, Valporate, Phenytoin
What is status epilepticus?
This is a medical emergency.
Defined as having a seizure lasting >5 minutes or >1 seizure within 5 minutes.
Can lead to permanent brain damage or even death.
What are the causes of status epilepticus?
AED withdrawal Non compliance Alcohol use/withdrawal Illicit drug Current infection Progression of underlying disease (tumour, encephalitis etc)
How is status epilepticus managed?
ABCDE
Start timing seizure
>5mins give 4mg IV lorazepam. (In the community would give buccal midazolam or rectal diazepam if unavailable or preferred) If uncertain of duration of seizure still give.
Repeat again if after 5 mins still seizure
Prepare the phenytoin incase the seizure still persists.
If >25mins seizure give 20mg/kg over 20mins of phenytoin.
IV valproate
Notify ITU.
Refractory status >30mins
General anaesthesia-high dose Propofol
Continue for 12-24hrs
What is the differential for epilepsy?
Vasovagal syncope
More likely epilepsy if Px has cyanosis, lateral tongue bite, post ictal amnesia(not confusion), rhythmic tonic clinic jerk, duration >2mins.
Less likely epilepsy- tongue tip bite, pallor, post event fatigue, brief twitching and jerking, associated trigger- may encourage collapsing.
Both can have incontinence, confusion on arousing.
How would you address a neurological problem?
Take a detailed Hx.
Look at distribution of symptoms
Onset- if sudden usually vascular
Type of symptoms? Motor or sensory?
These can help localise the lesion to a location- left/right/cerebellum/brainstem etc.
What are the causes of neuromuscular weakness?
Motor neurone disease Myasthenia gravis Guillain Barre syndrome Muscular dystrophies Multiple sclerosis
What is myasthenia gravis?
Disease of the neuromuscular junction.
Autoantibodies bind to the Ach receptors.
Leading to muscle weakness with easy fatigability.
Increases with exercise relieves with rest.
Varies from mild weakness of a few muscle groups to more severe weakness of several muscle groups.
How is myasthenia gravis classified?
Based off :
Antibody specific- The antibody specificity: acetylcholine; muscle-specific receptor tyrosine kinase (MuSK), LRP4 or seronegative.
Thymus histology- Thymitis, atrophy or thymoma.
Age of onset- Bimodal distribution (females usually get early, males usually late)
Course- Ocular or generalised
What is seronegative myasthenia gravis?
Seronegative to usual test but may have MUsk.
Usually female, <40yrs, 1/3 don’t respond to acetylcholinesterase.
How does myasthenia gravis present?
The main and usually first presentation is ocular symptoms.
Most then progress to generalised MG.
Muscle fatigue post exercise:
-Ask Px to count to 50 then notice their voice is less audible as they fatigue.
-Can ask Px to look at a point over their forehead, can’t do this for more than a few seconds if ocular involvement.
Ptosis, diplopia.
Weakness of proximal muscles
Symmetrical weakness of muscles can lead to difficulty walking, sitting, holding head up.
Muscle tone, reflexes and sensation is normal, no muscle wasting.
May have seizure.
Bulbar involvement
How does myasthenia gravis progress?
Disease progression occurs in the first year, if not second year of diagnosis. If has not progressed after this, then less likely to progress.
If restricted to extrinsic ocular muscles and LPS then ocular myasthenia.
Remission is rare, although if they do occur most will occur in the first 3 yrs of treatment.
Respiratory compromise- Weakness of muscles of ventilation or pharyngeal muscles can lead to this. Need ventilation, monitor O2 sats and vital capacity.
How is myasthenia gravis investigated?
If serum AChE is +ve then no further testing required.
Clinical diagnosis + detection of specific antibodies (i.e. anti-AChR, anti-MuSK or anti-LRP4) + ice test for ptosis.
TFTs
Negative serology can warrant MRI brain
Thymus CT/MRI
EMG- repetitive nerve stimulation to look for fatigability
CT thorax
How is myasthenia gravis managed?
First line- AChE inhibitors (pyristagmine) along with immunosuppression.
If unresponsive then corticosteroids, azathioprine or thymectomy (beneficial with/out thymoma present) are used as first line.
[Alternatives to azathioprine include ciclosporin, methotrexate or cyclophosphamide.]
Rituximab is becoming increasingly used.
Swallowing difficulty- Dietary advice.
New born babies can have transient myasthenia from myasthenic mother, regardless of if she is well controlled- need neonatal high dependency support.
What is myasthenia crisis?
Refers to worsening muscle weakness leading to respiratory failure requiring intubation and mechanical ventilation.
Occurs in first yr, can be first indicator of MG.
Increased risk post surgery or RTI.
Manage with immunoglobulins, corticosteroids, and plasma exchange.
How would you distinguish between a cholinergic crisis and a myasthenic crisis?
Cholinergic crisis would occur after having too much anticholinergic medicine. Px presents with muscle fasciculation, pallor, sweating, hypersalivation and small pupils.
DifferitatingH
Brisk reflex- UMN (up going toe)
Missing reflex- LMN
Areas and symptoms
Brain- left/right- opposite side
Brain stem- stroke
Double vision differential
Cranial nerve? 3/6th
MG
Thyroid eye disease (asymmetric infiltration)
Apthophysiology
Thymidine tumour/hyperplasia
Associated with other Ai diseases I.e SLE, RA, thyroid etc
Precipitants of MG
Emotional stress
Pregnancy
Messes
Drugs- aminoglycosides, BB, CCB, chloroquine etc- can still give but be aware of precipitating symptoms
What is Guillain Barre syndrome (GBS)?
Affects the PNS- demyelination and axonal degeneration resulting in acute, ascending and progressive peripheral neuropathy.
Weakness, paraesthesia and hyporeflexia.
Usually triggered by an infection
Clinical diagnosis
Length dependent neuropathy- i.e. the nerves further away e.g. the feet are affected first.
What is the pathophysiology of GBS?
Usually following a GI or respiratory infection; Campylobacter jejuni, HIV, EBV, CMV.
Thought the antibodies to the infectious organisms also attack the peripheral nerves antigens.
What are the subtypes of GBS?
AIDP- 95% of GBS
AMAN
AMSAN
Dyautonomia- extremely disabling; vision, dry mouth, urination, can’t get up when extremely flat since low B
What are the RF for developing GBS?
What are the complications of GBS?
Respiratory/GI infection 1-3wks prior.
Zika virus.
Vaccinations: live and dead vaccines have been implicated.
Malignancies - eg, lymphomas, especially Hodgkin’s disease.
Pregnancy: incidence decreases during pregnancy but increases in the months after delivery.
Complications- Respiratory failure, aspiration, DVT autonomic
How does GBS present?
LMN signs Muscle weakness- Starts at lower extremities and ascends symmetrically. Max severity reached after 2wks Facial weakness, dysarthria, dysphagia. Severe- Respiratory failure
Neuropathic pain, especially in legs and back.
Reduced/absent reflexes
Sensory symptoms starting at lower extremities. Glove and stocking pattern of sensory loss.
Autonomic symptoms: reduced sweating, reduced heat tolerance, paralytic ileus and urinary hesitancy. Severe autonomic dysfunction may occur.
How would GBS present on examination?
Hypotonia.
Demonstrable altered sensation or numbness.
Reduced or absent reflexes.
Fasciculation may occasionally be noted.
Facial weakness - may be asymmetrical.
Autonomic dysfunction - fluctuations of heart rate and arrhythmias, labile blood pressure and variable temperature.
Respiratory muscle paralysis.
How is GBS investigated?
Diagnosis is clinical but following investigations may prove useful.
Electrolytes- Some get SIADH
Lumbar puncture- Most have increased CSF protein count
Antibody screen
Spirometry- FVC can indicate need for ICU
Nerve conduction studies
ECG- 2nd/3rd AV block, ST depression etc.
Stool culture/throat swab- looking for cause.
Otherwise prognosis if much different if not improved after 4 weeks- CIDP- treated then improve then treated. Multiphasic
How is GBS managed?
What is the prognosis of GBS?
Plasma exchange IV immunoglobulin if started within the first 2wks of onset can be as useful as PE. DVT prophylaxis ITU admission Pain relief
Most make a full recovery, 20% still have some neurological problems, where 50% of these are severely disabled.
What are muscular dystrophies?
Inherited disorders of muscle weakness.
Different depending on age of onset, severity of muscle weakness, muscles affected etc.
Inherited gene leads to lack or deficiency in a particular protein. This leads to damaged muscle fibres and muscle weakness. The resulting weakness will be dependent on the gene and protein involved.
How do muscular dystrophies present?
Muscle weakness Can occur at any age- Baby- floppiness Older babies/young children- Failure to reach motor milestones Muscle wasting Muscle hypertrophy Myopathy Contractures Some types of MD can affect the heart. In some cases, there may be symptoms of heart disease without much in the way of muscle weakness.
What are the different types of muscular dystrophies?
Duchenne MD- Most common and most severe. Affecting arms and legs, with early muscle weakness. Age 12- need wheelchair. Affects boys but girls carriers. Heart and breathing problems become serious- live till 20yrs old.
Becker’s MD- Similar to DMD but les severe and occurs aged 20 so at 40/50yrs old unable to walk with developing heart and breathing problems. Boys affected, women carry.
Limb-girdle MD- Affect top of arms and legs. Severity dependent on type, affects both genders.
Fascioscapulohumeral MD- Affecting males and females, muscles of the face/shoudlers/upper arm. Onset 40-50yrs.
Emery Driefuss MD- Child/Adolescence. Affecting muscles of shoulder/upper arms and lower limbs.
Oculopharyngeal MD- Onset 50-60yrs, affecting muscles of eyes/throat. Present droopy eyes/difficulty swallowing.
How are muscular dystrophies investigated?
Bloods- Elevated CK Muscle biopsy- protein analysis Genetic analysis Electromyogram- observes muscle activity. Muscle US
How are muscular dystrophies managed?
No cure Physiotherapy- For joint mobility Steroids- For muscle strength Practical aids Follow ups Specific treatment i.e. of contractures.
What is motor neurone disease (MND)?
What are the main RF?
Neurodegenerative condition affecting the brain and spinal cord leading to paralysis and eventually death.
Commonly due to ALS (amyotrophic lateral sclerosis)
Other forms do exist and may occasionally occur, although rare.
Male, increasing age (60-70yrs), genetics.
What is the pathophysiology of MND?
Cause is unknown although importance of mitochondrial abnormality and oxidative stress of motor neurones is a possibility.
Leads to a LMN and UMN picture of muscle paralysis with LMN signs predominating.
How does MND present?
Progressive muscular weakness, first presenting as isolated symptoms.
First presents with emotional lability, behavioural change, FT dementia.
Functional muscle weakness (falling, reduced dexterity)
Muscle wasting, twitching, cramps, stiffness
Speech/dysphagia problems
Dyspnoea/orthopnoea
Particularly ALS- Starts in a particular region: Limb (commonly) Bulbar (20%) Respiratory (less likely)
How is MND investigated?
No investigation to diagnose the condition, but can be used to exclude other causes.
EMG and nerve conduction studies show characteristic pattern requiring careful interpretation.
CT/MRI brain/SC can rule out similar presenting pathologies.
Blood test to exclude i.e. B12/folate deficiency, HIV etc.
Muscle biopsies for exclusion.
How is MND managed conservatively?
Incurable disease with a distressing disability preceding it.
If suspect refer to get diagnosis
Offer MDT support.
Encourage physiotherapy and speech therapy.
Dietician
Exercise
PEG tube when Px can’t feed
Encouraging other modes of communication.
NIV
How is MND managed medically?
Riluzole used in ALS since disease modifying efficacy. Muscle cramps- quinine Increased tone/stiffness- baclofen May need anti depressants May need pain relief
Discuss end of life care
Survival is 2-4yrs.
What is multiple sclerosis (MS)?
What are the types of MS?
Autoimmune condition leading to repeated episodes of inflammation of the CNS.
Relapsing remitting MS- Px has an episodes of good health/remission followed by sudden relapse. Don’t always get 100% remission. (Commonly teenage/adolescent females)
Secondary progressive- Progression from RRMS. More/worsening symptoms with fewer remissions.
Primary progressive- From beginning symptoms gradually develop and worsen over time. (Usually middle aged men)
What is the pathophysiology of MS?
Autoimmune; may be precipitated by either environment (early viral infections) or genetics.
Leads to multiple areas of sclerosis along neurones, this leads to slowed/blocked transmission to brain/SC and so reduced sensation and movement.
What are the RF for MS?
F:M is 2:1
FHx
Pregnancy does not change the risk, although lowered risk of relapse during pregnancy, higher post partum.
How does MS present initially?
The main first symptoms are as followed:
1) Optic neuritis- sight impairment/hemianopia. Optic neuritis.
2) Brainstem lesion- Double vision, facial pain, dysphagia, vertigo, facial weakness, diminished taste, hearing impairment a, weakness nystagmus.
3) Transverse myelitis- An acute episode of weakness or paralysis of both legs, with sensory loss and loss of control of bowels and bladder; requires urgent hospital admission.
What are the other presentations of MS?
Facial- Bells palsy, trigeminal neuralgia, paroxysmal dysarthria, ataxia.
Hearing/balance- Deafness, vertigo, vomiting
Cognitive; visual, auditory, higher mental function
Depression
Taste and smell alters
Symptoms persists for several wks-months then will either get better and resume the original gradual decline or will get worse.
Several different presentations.
How is MS investigated?
Check FBC, inflammatory markers, U&E, LFT, TFT, glucose, HIV serology, calcium and B12 levels to exclude differentials.
Electrophysiology to detect demyelination.
MRI- 95% of patients have periventricular lesions and over 90% show discrete white matter abnormalities. (May show lesions of inflammation within the spinal cord or within the hemispheres, less commonly medulla)
CSF- Rise in protein level.
Diagnose with Mc Donald criteria.
How is MS managed conservatively?
- Px to notify DVLA
- Exercise
- Eat healthy
- No smoking
- Vitamin D OTC everyday
- Referred to MS nurse
After diagnosis of MS, and having checked bloods for any latent TB or dormant infections, a Px is initiated on DMT.
If sudden onset of relapse (within 12-24hrs) then give either 500mg/day methylprednisolone for 5 days or admit for IV infusion. Give gastric protection. Rule out UTI first as cause of symptoms.
What is the role of DMT in MS?
DMT is recommended for RRMS to help prevent the recurring of a relapse, by working as an immunosuppressor. There are different levels of intensity and different formats. I.e. the more low level ones are tablet, whereas other higher forms are 6 monthly infusions.
Examples include Interferon beta and Teriflunomide (used in active MS- two relapses within 2yrs).
Recently, Alemtuzumab has found to be the only DMT useful in treating PPMS.
NB- Women should stop DMT 12 months prior to becoming pregnant.
Autonomic dysfunction and complications
Arrhythmia By Pseudo obstruction- lieu’s Repisroty failure- Most people make a full recovery- self limiting- takes weeks to months to achieve 25% need help with breathing- ITU
Other complications
Pain
Manage
Close obs etc
Severe- IV IG, plasmapheresis in first 2 weeks
Prognosis s
25% need ventilation
Testing visual field defect
Test by confrontation- check your vision against a Px.
Ask when the Px can see the finger/white pen.
To test macular function use red pen and ask when it appears red.
Need Px to maintain point of fixation I.e. on bridge of your nose.
Move the pen slowly
Use systematic approach
Repeat if you find a defect- need for find at least 2 points of defect to find the boundaries. Move the pen horizontally, moving down each time and move vertically moving across each time.
What is a bitemporsl hemianopia?
Normal visual acuity so unlikely cataract fr ipbilateral optic nerve disorder.
Not homologous since in two different VF of the eye; therefore not at optic tract, radiations or behind the chasm.
This is therefore from the chiasm.
What
Optic chiasm- bilateral hemianopia
Complete lesion of optic tract- no Ono iOS complete hemianopia
Incomplete- bilateral incomplete hemianopia
Geniculate- typically vascular injury- wedged shaped homonimous- lateral genicukjs
Lesions of optic radiations- quadrantinopias
Visual cortex lesions homonomous hemianopia with macular sparring
Affecting the higher orders of vision- a
Causes of bitmportal hemianopia
Affecting the optic chiasm
Neoplasm
Inflammatory
Vascsuly
Chronic open angle glaucoma
Find optic disc with fundocspy- if found easily ask has this pt got atrophy? Easy to find boundaries.
If difficult then does this Px have papillodedma?
Optic neuritis
Central Scotoma
Colour vision
Pupils
Equal diameter?
Reaction to light?
Round?
Abnormal one usually doesn’t react to light, unilateral ptosis. Common causes- 3rd nerve palsy Hornets syndrome Tonic pupil Pharmacological pupil
Binocular Diplopoda likely neurological.
Monocular persists after covering eye- functional or ophthalmic cause.
Posterior communicating artery aneurysm
Pupil involved initially.
Can compress on 3rd nerve- giving third never palsy
Painful
Short history
Diagnose using angiogram- can lead to subarachnoid haemorrhage.
Horners syndrome
Sympathetic palsy Partial ptosis, constricted pupil Congenital horners gives paler iris Test by turning lights off- pupils will dilate passively if horners syndrome as opposed to actively. May get anhydrosis No visual symptoms
Causes of horners
Sympathetic chain
No decussation therefore if ls lesion then LS hornrrs.
Causes me congenital , clusterbheadache, structural pathology
Pan coast tumour
Pancoust turner @ti
Pain @ medial forearm. Muscle wasting @ thenart intercede.
Tonic pupil
Pupil larger than another one t No ptosis o eye movement usually reacts to light but after prolonged illumination reluctant to dilate again Parasympathetic version of howlers Oval pupil No symptoms
4th nerve palsy
Notice when looking to down, reading
Tilt heads away from affected site- esp in congenital
Looking out and down- difficult to look down
Common congenital
6th nerve palsy
LR
Ocular myasthenia
Bilateral pto
Brainstem
Compact therefore small lesions can have large effects Feautures Cranial nerve palsies Complex eye movement disorder 2+ is BS territory.
UMN
Ok
LM
Mdd
Think of cutting a nerve
Inter nuclear ophthlmaplegia
Impairment of addiction Abducting eye develops nystagmus Related to MS esp in young Doesn’t look like anything else ask the Px to look between two points- look right then left then right- looking for slow abduction. I.e. eye moving towards nose is slower
