Neurology Flashcards
How does a medulloblastoma present?
Arise in midline of posterior fossa and may spread through CNS via CSF –> spinal metastases
–> truncal ataxia, coordination difficulties, abnormal eye movements and morning vomiting
Younger child
50% 5 year survival
How does a brainstem glioma present?
Commoner in young children
Cranial nerve defects, pyramidal tract signs, ataxia and normal ICP (refusing to walk, unable to climb stairs)
Very poor prognosis
How does a craniopharyngioma present?
Developmental tumour arising from remnants of Rathke’s pouch
–> bitemporal hemianopia, pituitary failure (growth failure, weight gain and diabetes insipidus)
Good survival
What are clinical features of brain tumours?
Headache - worse in morning Vomiting - worse in morning Behaviour/personality changes Visual disturbances Papilloedema Separating of fontanelles Increased head circumference Head tilt Developmental delay
Spinal tumours –> back pain, peripheral weakness of arms/legs or bladder/bowel dysfunction
How does an astrocytoma present?
Vary from benign to highly malignant
Occur in cerebral hemispheres, thalamus an hypothalamus
–> seizures, headaches, hemiplegia, focal neurological signs
Teenager
Poor prognosis
What causes a motor deficit?
Central motor deficit - cerebral palsy
Congenital myopathy
Spinal cord lesions - spina bifida
Global developmental delay
How do gross motor skills develop?
Newborn - flexed limbs, head lag pulling up 8 weeks - raises head to 45 degrees 6 months - sits unsupported 9 months - crawling 10 months - cruising 12 months - walks unsteadily 15 months - walks steadily
How do fine motor skills and vision develop?
6 weeks - follows moving objects 4 months - reaches for toys 6 months - grasps toys 7 months - passes hand to hand 10 months - pincer grips 18 months - makes marks with pen 5 years - draws triangle
What is cerebral palsy?
An abnormality of movement and posture
May be associated with disturbances of cognition, communication, seizure disorder
Lesion is non-progressive but manifests over time
Must occur before 2 years
What causes cerebral palsy?
Antenatal (80%) - vascular occlusion, cortical migration disorders, structural maldevelopment of brain
Perinatal (10%) - hypoxia-ischaemic injury, peri-ventricular leucomalacia
Postnatal (10%) - meningitis/encephalitis, encephalopathy, head trauma, hypoglycaemia, hyperbilirubinaemia
How does cerebral palsy present?
- Abnormal limb/trunk posture or tone with delayed motor milestones
- Feeding difficulties, slow feeding, gagging, vomiting
- Abnormal gait
- Asymmetric hand function before 12 months
- Persistence of primitive reflexes
What is spastic cerebral palsy?
Damage to upper motor neurone pathway (pyramidal or corticospinal tract)
Increased limb tone (spasticity) and reflexes
Presents early
Hemiplegia - unilateral involvement of arm and leg
- present at 4-12 months
- fisting of hand, flexed arm
- tiptoe (toe-heel) walk
Quadriplegia - all four limbs affected (severe)
- involvement of trunk, poor head control
- associated with seizures, microcephaly and intellectual impairment
Diplegia - all limbs, but legs worse than arms
- associated with pre-term birth due to peri-ventricular brain damage
What is dyskinesic cerebral palsy?
Involuntary movements more evident with active movement and stress
Muscle tone is variable and primitive reflexes continue
- chorea - irregular, sudden and brief non-repetitive movements
- athetosis - slow, writhing movements occurring distally
- dystonia - simultaneous contraction of agonist and antagonist muscles of the trunk and proximal muscles –> twisting appearance
Intellect may be unimpaired
Commonly caused by HIE –> damage to basal ganglia
What is ataxic (hypotonic) cerebral palsy?
Mostly genetic
Early trunk and limb hypotonia, poor balance
Intention tremor
Ataxic gait
How is cerebral palsy treated?
Physical therapy
Devices and equipment - crutches, casts (strengthen muscles in another part of the body), wheelchairs
Antispasmodics - baclofen, botox, diazepam
Antiepileptics - lamotrigine
Anticholinergics (help with uncontrollable movements and drooling)
Surgery - increase range of movement, prevent hip dislocation, scoliosis, selective dorsal rhizotomy (cut nerves to tight muscles in legs)
What are generalised seizures and which types are there?
Discharges arise from both hemispheres Includes: - absence - myoclonic - tonic - tonic-clonic - atonic
Describe an absence seizure.
Transient loss of consciousness with abrupt onset and termination
Can be precipitated by hyperventilation
Describe a myoclonic seizure.
Brief but repetitive jerking movements of limbs, neck and trunk
Describe a tonic seizure.
Increase in tone therefore very stiff
Describe a tonic-clonic seizure.
Rhythmic contraction of muscle groups following tonic phase
Fall to ground and become cyanosed
Tongue biting and incontinence
Followed by unconsciousness or deep sleep
Describe an atonic seizure.
Often combined with myoclonic jerk followed by loss of muscle tone causing drop to floor
What is a focal seizure?
Discharges arise from one hemisphere
How does a frontal seizure present?
Motor/premotor cortex
Clonic movement
Or assymmetrical tonic seizure
How does a temporal seizure present?
Most common type of all
Strange warning feelings with smell and taste anomalies
Lip-smacking
Deja-vu
How does an occipital seizure present?
Visual distortion
How does a parietal seizure present?
Altered sensation or distorted body image
What is West syndrome?
4-6 months EEG shows hypsarrhythmia Flexor spasms of head, trunk and limbs followed by extension of arms Spasms occur for 1-2 seconds Repear 20-30 times
What is Lennox-Gastaut syndrome?
1-3 years
Drop attacks, tonic seizures and atypical absences
What is childhood absence epilepsy?
4-12 years
EEG shows 3 sec spike and wave discharge
What is benign epilepsy?
Tonic-clonic seizures in sleep
What is early onset benign childhood occipital epilepsy?
Periods of unresponsiveness in young children
Hallucinations in older children
What is juvenile myoclonic epilepsy?
Myoclonic seizures/generalised tonic-clonic or absences after waking
What are the side effects of valproate?
Weight gain
Hair loss
Liver failure
What are the side effects of carbamazepine?
Rash
Neutropenia
Hyponatraemia
Ataxia
What are the side effects of lamotrigine?
Rash
What are the side effects of benzos?
Sedation
Tolerance
What are causes of funny turns?
Breath holding attacks Reflex anoxic seizures Syncope Migraine BPV Cardiac
What are common causes of ataxia?
Acute - medications, drugs, alcohol
Post viral - varicella
Posterior fossa lesions
Genetic and degenerative disorders - ataxic cerebral palsy, Friedreich’s ataxia, ataxia telangiectasia
What is Friedreich’s ataxia?
Worsening ataxia
Distal wasting in legs
Absent lower limb reflexes except Babinski sign
Death at 40 due to cardiorespiratory compromise
What is ataxia telangiectasia?
Disorder of DNA repair
Mild delay in motor development in infancy
Subsequent deterioration requiring wheelchair for mobility
What is the typical history of breath holding?
Cyanotic - occurs in response to anger or frustration, skin turns blue-purple
Pallid - occurs in response to fear, pain or injury esp after head injury
What are common causes of developmental regression?
Battens disease - 4-10 years, onset of visual problems and seizures
Retts syndrome
Leukodystrophies - dysfunction of white matter
Wilson’s disease - reduced synthesis of copper binding protein therefore accumulation in liver, brain, kidney and cornea
SSPE - chronic, progressive encephalitis caused by persistant infection of immune resistant measles
What are the types of hydrocephalus?
Obstructive - within ventricular system or aqueduct
Communicating - obstruction at arachnoid villi, site of absorption for CSF
External - immaturity of villi not absorbing fast enough
What are the common causes of macrocephaly?
Head circumference >98th centile
Tall stature Familial Raised ICP Hydrocephalus Chronic subdural haematoma Cerebral tumour
What are the common causes of microcephaly?
Head circumference
What is a tension headache?
Symmetrical headache with gradual onset
Usually no other symptoms but could have abdo pain
What is a migraine?
Without aura (90%), last 1-72hrs
Bilateral, pulsatile over temporal or frontal areas
GI disturbances - N+V, abdo pain, photo/phonophobia
Physical activity aggravates
With aura (10%) - visual disturbances Last a few hours and need to sleep in dark room
How do reflex anoxic seizures present?
In infants or toddlers
Triggers - pain, cold food, fright or fever
Become very pale and fall to floor
Due to cardiac asystole from vagal inhibition
What causes subdural haematoma?
Tearing of veins across subdural space
Characteristic in NAI
Retinal haemorrhage usually present
Can occur falling from height
How does craniosynostosis present?
Sutures of skull bone start to fuse during infancy
Premature fusion causes distortion of head shape, usually localised
May be part of Crouzon syndrome
How does myotonic dystrophy present?
Delayed relaxation after sustained muscle contraction can be seen on electromyography
Onset between 20-50 years
Poor feeding, failure to meet milestones and hypotonia
Progressive distal muscle weakness, ptosis, carp mouth, cataracts, frontal balding, cardiomyopathy
What is Guillain-Barre?
2-3 weeks post URTI, may take up to 4 years?!?
Ascending symmetrical weakness with loss of reflexes and autonomic involvement
Involvement of bulbar muscles leads to difficulty chewing and swallowing (may require ventilation)
Recovery make take up to 2 years
CILP is chronic version
What is Bells palsy?
Isolated lower motor neurone paresis of 7th cranial nerve –> facial weakness
?HSV
Corticosteroids may help in first week
What is Charcot Marie Tooth?
Distal muscle wasting and sensor loss with progression
Onset by 10 years:
Spinal deformities
No cure but most have normal life expectancy
What is spinal muscular atrophy?
Autosomal recessive degeneration of anterior horn cells –> progressive weakness and wasting of skeletal muscle
Type 1: very severe presenting in early infancy and die within 12 months
Type 2: can sit but not walk
Type 3: do walk and present later
What indications and contraindications for LP?
Indications
- suspected meningitis or encephalitis
- suspected subarachnoid if CT is normal
- septic screen in neonates
Contraindications
- cardiorespiratory instability
- focal neurological signs
- raised ICP
- coagulopathy
- local infection at site
What are the values of normal CSF?
Clear fluid
Few white cells
0.15-0.4g/l protein
Glucose >50% of blood
What are LP values in bacterial meningitis?
Turbid (cloudy) fluid
Very increased neutrophils
Increased protein
Decreased glucose
What are LP values in viral meningitis?
Clear fluid
Increased lymphocytes
Normal or increased protein
Normal or decreased glucose
What are LP values in TB meningitis?
Turbid/clear/viscous fluid
Increased lymphocytes
Very high protein
Very low glucose
What are the diagnostic criteria for paediatric migraine?
5 attacks lasting 1-72 hours
Unilateral, pulsing, severe pain, aggravated by physical exercise
With N+V or photo/phonophobia
Made better by sleep
How does tension headache present?
Symmetrical headache of gradual onset like a band
Onset in evening
What features suggest a space occupying lesion?
Headache worse lying down Morning vomiting Night time waking Change in mood/personality Visual field defect Cranial nerve abnormalities
How are headaches managed?
Rescue treatments
- NSAIDs
- anti-emetics (prochlorperazine, metochlopramide)
- serotonin agonists (sumatriptan)
Prophylactic
- pizotifen
- propanolol
- sodium channel blockers (valproate)
