Neurology Flashcards
Seizures & epilepsy
- seizures = paroxysmal abnormality of motor, sensory, autonomic and/or cognitive function due to transient brain dysfunction
- epilepsy = excessive and hypersynchronous electrical activity, typically in neural networks in all or part of the cerebral cortex
Epilepsy causes
Genetic
Structural, metabolic - cerebral damage, cerebral tumour, neurodegenerative disorders, cerebral vascular occlusion,
Acute symptomatic seizures
Due to any cortical brain injury or insult, at the time of the trauma/illness
- stroke, traumatic brain injury, intracranial infection
- hypoglycaemia, hypocalcaemia, hypomagnesaemia, hyponatraemia/hypernatraemia
- poisons/toxins
Febrile seizures
Epileptic seizures accompanied by a fever in the absence of intracranial infection
Non-epileptic seizures
Convulsive syncope - cardiac syncope, neurally mediated syncope, expiratory apnoea syncope
Sudden rise in intracranial pressure
Sleep disorders
Functional/medically unexplained
Floppy infant
- can be used to describe:
- decreased muscle tone (hypotonia)
- decreased muscle power (weakness)
- ligamentous laxity and increased range of joint mobility
Hypotonia
- hypotonia - congenital hypotonia is defined as a subjective decrease of resistance to passive range of motion around the joint in a newborn
- causes:
- hypoxic ischaemic encephalopathy
- intracranial haemorrhage
- cerebral malformations
- congenital infections
- spinal muscular atrophy
- infant botulism
- causes:
Floppy infant ix
- bloods: FBC, U&Es, LFTs, bone profile, magnesium, blood gas, ammonia, glucose
- cranial USS
- consider a septic screen
- consider plasma amino acids and organic acids & urine organic acids → metabolic disorder
- CK
- consider screening to investigate for SMA
Floppy infant mx
- depends on the cause of hypotonia
- some babies that have severe illness will need respiratory support & feeding support
- MDT approach is required no matter the cause
- OT
- PT
- SALT
- dietician
- likely neurology involvement
Headache
Primary - four main groups (due to a primary malfunction of neurons and their networks)
- migraine
- tension-type headache
- cluster headache
- other primary headaches - eg. primary stabbing headache
Secondary - symptomatic of some underlying pathology eg. space-occupying lesions, raised ICP
Trigeminal & other cranial neuralgias & other headaches → root pain from herpes zoster
Only investigate if any red flag features
Headache red flag symptoms
Worse lying down/coughing/straining
Wakes up child
Associated confusion and/or morning or persistent N&V
Recent change in personality, behaviour or educational performance
Headache red flag signs
Growth failure
Visual field defects (craniopharyngioma)
Squint
Cranial nerve abnormality
Torticollis (neck spasms & twists to side)
Abnormal coordination
Gait
Papilloedema
Bradycardia
Cranial bruits
Generalised tonic-clonic seizures
- loss of consciousness
- tonic (muscle tensing) and clonic (muscle jerking) movements
- typically tonic before clonic
- may be associated tongue biting, incontinence, groaning & irregular breathing
- after → prolonged post-ictal period where person is confused, drowsy & feels irritable/low
- management:
- first line: sodium valproate (except girls > 10)
- second line: levetiracetam/lamotrigine (first line for girls > 10)
Focal seizures
- start in the temporal lobes
- affect hearing, speech, memory & emotions
- various ways that focal seizures can present:
- hallucinations
- memory flashbacks
- deja vu
- doing strange things on autopilot
- management:
- first line: lamotrigine or levetiracetam
- second line: carbamazepine or oxcarbozepine or zonisamide
Absence seizure
- typically happen in children
- patient becomes blank, stares into space & abruptly returns to normal
- during the episode, they are unaware of their surroundings & won’t respond
- 10-20 seconds
- management:
- first line: ethosuximide
- second line: sodium valproate
Atonic seizures (drop attacks)
- atonic seizures (drop attacks)
- characterised by brief lapses in muscle tone
- don’t usually last more than 3 minutes
- typically begin in childhood
- may be indicative of Lennox-Gastaut syndrome
- management:
- first line: sodium valproate
- second line: lamotrigine
Myoclonic seizures
- present as sudden brief muscle contractions
- usually remain awake
- management:
- first line: sodium valproate or levetiracetam
Infantile spasms
- characterised by clusters of full body spasms
- poor prognosis (1/3 die by age 25), 1/3 are seizure free
- management:
- first line: prednisolone & vigabatrin
Febrile convulsions
- seizures that occur in children whilst they have a fever
- only occur in children between the ages of 6 months and 5 years
- slightly increases risk of developing epilepsy in the future
Epilepsy ix
- EEG can show typical patterns in different forms of epilepsy & support the diagnosis
- perform after the second simple tonic-clonic seizure
- MRI brain
- first seizure < 2 years
- focal seizures
- no response to first line anti-epileptic medications
- additional investigations
- ECG
- blood electrolytes
- blood glucose
- blood cultures, urine cultures & LP
Epilepsy mx
- general advice
- take showers rather than baths
- be very cautious swimming
- be cautious with heights
- be cautious with traffic
- be cautious with any heavy, hot or electrical equipment
- avoid driving until meet criteria
- medication
- seizures
- put patient in a safe position
- recovery position, something soft under head
- remove obstacles that could lead to injury
- make a note of start & end time of seizure
- call an ambulance if lasting > 5 minutes or first seizure
Status epilepticus
- seizure lasting more than 5 minutes or 2 or more seizures without regaining consciousness
- management in hospital:
- secure airway
- high concentration oxygen
- assess cardiac & respiratory function
- check blood glucose levels
- gain IV access
- IV lorazepam, repeat after 10 minutes if seizure continues
- seizures persist after final step → IV phenobarbital/phenytoin
- medical options in the community → buccal midazolam or rectal diazepam
Extradural haemorrhage
- arterial/venous bleeding into the extradural space
- usually follows direct head trauma, often associated with skull fracture
- tearing of the middle meningeal artery as it passes through the foramen spinosum of the sphenoid bone
- diagnosis confirmed by CT scan
Extradural haemorrhage presentation
Lucid interval
Seizures secondary to increasing size of the haematoma
Focal neurological signs with dilatation of the ipsilateral pupil, paresis of the contralateral limbs & false localising unilateral/bilateral sixth nerve palsies
Young children - anaemia & shock
Extradural haemorrhage mx
Correct hypovolaemia
Urgent evacuation of the haematoma and arrest of the bleeding
Migraine without aura
Accounts for 90% of migraines
Presentation
- bilateral headache but may be unilateral
- characteristically pulsatile over the temporal or frontal area
- often accompanied by unpleasant GI disturbance - N&V, abdominal pain, photophobia & phonophobia
- aggravated by physical activity
- relieved by sleep
Migraine with aura
Accounts for 10% of migraine
Headache is preceded by an aura (visual, sensory or motor)
Presentation
- absence of problems between episodes
- frequent presence of premonitory episodes
- visual disturbance aura:
- negative phenomena → hemianopia (loss of half the visual field) or scotoma (small areas of visual loss)
- positive phenomena → fortification spectra (seeing zigzag lines)
- unilateral sensory/motor symptoms = hemiplegic migraines
Migraine mx
Advice & safety-netting
Rescue treatments
- analgesia - paracetamol and NSAIDs
- antiemetics - prochlorperazine or cyclizine
- triptans - nasal preparation of this is particularly useful in children early in a migraine attack
- physical treatments - cold compresses, warm pads, topical forehead balms
Prophylactic treatments (headaches are frequent and intrusive)
- sodium channel blockers
- beta-blockers eg. propranolol - contraindicated in asthma
- tricyclics eg. pizotifen - can cause weight gain & sleepiness, amitriptyline - can cause dangerous arrhythmias in overdose
- acupuncture
Psychological support
- relaxation & other self-regulating techniques
- addressing lifestyle issues
- ensuring adequate and regular rest, play, water & food
Muscular dystrophies
Genetic conditions that cause gradual weakening & wasting of muscles
Muscular dystrophies types
- Duchennes muscular dystrophy
- Beckers muscular dystrophy
- myotonic dystrophy
- facioscapulohumeral muscular dystrophy
- oculopharyngeal muscular dystrophy
- limb-girdle muscular dystrophy
- Emery-Dreifuss muscular dystrophy
Gower’s sign
- children with proximal muscle weakness use a specific technique to stand up from a lying position = Gower’s sign
- to stand up, they got onto their hands and knees, then push their hips up and backwards
- then, they shift their weight backwards & transfer their hands to their knees
- whilst keeping their legs mostly straight, they walk their hands up their legs to get body erect
- muscles around the pelvis are not strong enough to get their upper body erect without help of their arms
Muscular dystrophies mx
- no curative treatment
- aimed at allowing the person to have highest quality of life
- involves input from occupational therapy, physiotherapy & medical appliances
- surgical & medical management of complications eg. spinal scoliosis & HF
DMD
- caused by defective gene for dystrophin on the X-chromosome
- protein that helps hold muscles together at the cellular level
- X-linked recessive condition
- present around 3-5 years with weakness in the muscles around their pelvis
- tends to be progressive & eventually all muscles are affected
- wheelchair bound by the time they become a teenager
- life expectancy of around 25-35 years with good management of cardiac & respiratory complications
- oral steroids have shown to slow progression of muscle weakness, creatine supplementation can give a slight improvement in muscle strength
Raised IP
Brain & ventricles are enclosed by a rigid skull, they have a limited ability to accommodate additional volume
Additional volume will therefore lead to a rise in ICP
Raised IP causes
Idiopathic intracranial hypertension
Traumatic head injuries
Infection - meningitis
Tumours
Hydrocephalus
Raised IP clinical features
Headache
Vomiting
Reduced levels of consciousness
Papilloedema
Cushing’s triad - widening pulse pressure, bradycardia, irregular breathing
Raised IP ix & monitoring
Neuroimaging is key to investigate the underlying cause
Invasive ICP monitoring - catheter placed into the lateral ventricles of the brain to monitor the pressure
Raised IP mx
Investigate & treat underlying cause
Head elevation to 30 degrees
IV mannitol
Controlled hyperventilation - aim is to reduce pCO2
Removal of CSF - drain from intraventricular monitor, repeated LP, ventriculoperitoneal shunt
SMA
Rare, autosomal recessive condition that causes a progressive loss of motor neurones → progressive muscular weakness
Affects the lower motor neurones in the spinal cord
- fasciculations
- reduced muscle bulk
- reduced tone
- reduced power
- reduced/absent reflexes
SMA categories
- 1, 2, 3 & 4 (2 most common)
- SMA type 1 - onset in the first few months of life, usually progressing to death within 2 years
- SMA type 2 - onset within the first 18 months
- most never walk, but survive into adulthood
- SMA type 3 - onset after first year of life
- most walk without support, but subsequently lose that ability
- life expectancy close to normal
- SMA type 4 - onset in the 20s
- most retain ability to walk short distances but require a wheelchair for mobility
- everyday tasks can lead to significant fatigue
- respiratory muscles & life expectancy are not affected
SMA mx
- supportive & involves the MDT
- physiotherapy can be helpful maximising strength in the muscles & retaining respiratory function
- respiratory support with NIV → may be required to prevent hypoventilation & respiratory failure
- children with SMA type 1 may require a tracheostomy with mechanical ventilation → can dramatically extend life by supporting failing respiratory muscles
- PEG feeding may be required when a weak swallow makes swallowing unsafe
Subarachnoid haemorrhage presentation
Severe headache with rapid onset (’thunderclap headache’)
Vomiting
Confusion
Lowered level of consciousness
Seizures
Coma
Subarachnoid haemorrhage ix
CT head - identifies blood in the CSF
LP occasionally
MR angiography, CT or conventional angiography (cause is often an aneurysm or arteriovenous malformation)
Subarachnoid haemorrhage mx
Neurosurgery
Interventional radiology
Subdural haemorrhage
- results from tearing of the bridging veins as they cross the subdural space
- a characteristic lesion in nonaccidental injury caused by shaking or direct trauma & toddlers
- retinal haemorrhages are typical of shaking injury
- occasionally seen following a fall from considerable height
- rarely seen in association with brain shrinkage through atrophy or over drainage of hydrocephalus
Tension headache
Form of episodic primary headache
Chronic tension-type headache - defined as a tension headache occur on 15 or more days per month
Tension headache clinical features
‘tight band’ around the head/pressure sensation
Bilateral
Tends to be of a lower intensity than migraine
Not associated with aura, N&V or aggravated by routine physical activity
May be related to stress
Tension headache mx
Acute mx - aspirin, paracetamol or an NSAID
Prophylaxis - up to 10 sessions of acupuncture over 5-8 weeks
Low-dose amitriptyline
Homonymous hemianopia
Incongruous defects: lesion of optic tract
Congruous defects: lesion of optic radiation/occipital cortex
Macula sparing: lesion of occipital cortex
Homonymous quadrantanopias
Superior - lesions of the inferior optic radiations in the temporal lobe
Inferior - lesion of the superior optic radiations in the parietal lobe
PITS
Bitemporal hemianopia
Lesion of optic chiasm
Upper quadrant defect > lower quadrant defect = inferior chiasmal compression, commonly a pituitary tumour
Lower quadrant defect > upper quadrant defect = superior chiasmal compression, commonly a craniopharyngioma
