Neuro Flashcards
causes of abnormal motor development
central (CP), myopathy, spinal cord lesion (spina bifida), global developmental delay
what is cerebral palsy
abnormality in posture and tone, brain injuries before 2 years.
CP are the lesions progressive
no, clinical manifestations emerge over time
causes of CP antenatal
placental insufficiency- occlusion, chromosomal, genetic, infection
causes of CP
antenatal 80%, hypoxic-ischaemic encephalopathy 10%, postnatal 10%
causes of CP postnatal
meningitis, encephalitis, encephalopathy, hypoglycaemia, kernicterus, hydrocephalus
how does CP present
abnormal posture and tone, delayed motor milestones, feeding difficulties, abnormal gait, hand asymmetry before 1y
what happens to primitive reflexes in CP
may persist and become obligatory
what are the 3 types of CP
spastic, dyskinetic and ataxic
what signs are seen in spastic CP
UMN lesion so increased tone, brisk reflexes, extensor plantar responses. tone is velocity dependent so clasp knife can be seen. initial hypotonia at birth
3 main types spastic CP
hemiplegia, diplegia, quadriplegia
how does hemiplegic spastic CP present
unilateral involvement arm and leg; fisting affecting hand, flexed arm, pronated forearm, asymmetric hand function; tip toe walking. birth history may be normal
how does quadriplegic spastic CP present
all 4 limbs involved, severe, trunk involved- opisothonus, poor head control, low central tone.
what is quadriplegic assoc with and what can happen in birth to lead to it
seizures, microcephaly, intellectual impairment. hypoxic-ischaemic encephalopathy
how does diplegic spastic CP present
all 4 limbs involved but legs more than arms so hand function may appear normal. abnormal walking.
what can happen to cause diplegic
periventricular brain damage
what is asymmetrical hand function before 12m likely to be due to
hemiplegic spastic CP
what tracts are affected in spastic CP
pyramidal and corticospinal tracts
what is damaged in dyskinetic CP
basal ganglia, extra pyramidal
how does dyskinetic CP present
abnormal involuntary movements more obvious with active movement and stress. tone is variable. chorea, athetosis, dystonia. intellect can be unimpaired
what is ataxic CP
early trunk and limb hypotonia, poor balance, delayed motor development
what are the causes of ataxic CP
most genetically determined. if brain injury- signs on same side as lesion. cerebellum
causes of headache
tension- tight band like headache, common in adolescents usually with abdominal pain; migraine; raised ICP; sinusitis; benign intracranial hypertension
symptoms raised ICP
headache worse on lying down and when waking up, vomiting especially in the morning, visual field defects, CN 6 palsy, gait abnormalities, papilloedema (late sign)
causes of hydrocephalus
congenital, arnold-chiari malformation, subarachnoid haemorrhage, meningitis
features of hydrocephalus
large head circumference, sutures separated, bulging anterior fontanelle, if left untreated- setting sun sign and signs of increased ICP
what signs can be seen from anterior fontanelle
closes around 1 and a half. bulging- raised ICP, sunken- dehydrated
what is microcephaly
head circumference below 2nd centile
causes of microcephaly
familial (take mean of parents), congenital infection, brain injury- meningitis, hypoxia, hypoglycaemia, accompanise CP and seizures; autosomal recessive- developmental delay
what is macrocephaly
head circumference >98th centile
causes of macrocephaly
tall stature, familial, hydrocephalus, raised ICP, tumour, chronic subdural haematoma
what is a febrile seizure
seizure accompanied by fever in absence of intracranial infection due to meningitis/encephalitis
what happens in febrile seizure
usually brief generalised tonic clonic, usually early in infection when temperature is rising rapidly
what age is febrile seizure likely
6m-5y
how many patients will have further febrile seizures and what will make further seizures more likely
30-40%. more likely if younger child, started earlier on in the illness, family history, lower temperature when the convulsion occured
what is the chance of developing epilepsy with febrile convulsions
1-2% in simple seizures. 4-12% if it is complicated by having focal signs, prolonged seizures, repeated in the same illness
in febrile convulsion what must you always consider
bacterial cause eg meningitis as classical features may not be present if patient is
if history of prolonged seizures what can be given
rectal diazepam or buccal midazolam.
what is the normal length of a febrile convulsion and above which you would get worried
5 mins
causes of paroxysmal events in children
breath holding attacks, reflex anoxic seizures (head trauma, cold food, fright, fever), syncope, BPPV, pseudoseizures, epilepsy, induced illness (NAI), cardiac- prolonged QT
what are examples of generalised seizures
arise from both hemispheres. generalised tonic-clonic, myoclonic, atonic, absence
what is the most common focal seizure and what does it present with
temporal- aura, lip smacking and other automatisms, deja vu
what does frontal present with
motor/pre motor. clonic movements, asymmetrical tonic can be seen
what does parietal present with
altered sensation- dysaesthesia, distorted body image
what investigations should be done in child with seizures
EEG, 24h ambulatory EEG, video telemetry, MRI/CT to exclude brain lesions (tumour, infarct, malformation), PET to see hypometabolism
what is West syndrome
infantile spasms. occurs 4-6m. triad- spasms, learning difficulties and hypsarrhythmia on EEG. multiple bursts 20-30 spasms lasting 1-2s each
what can you use to treat West syndrome
vigabatrin and corticosteroids. poor prognosis
what is Lennox-Gastaut syndrome
slightly later onset seizures- 1-3years. drop attacks- astatic seizures, tonic, atypical absences. neurodevelopmental arrest. poor prognosis
what is childhood absence epilepsy and when does it come on
4-12 year olds. absence- for seconds not longer than a minute, then may twitch eyelids or hand. developmentally normal, females 2/3.
how could childhood absence be induced in the clinic
hyperventilation
what is the prognosis of childhood absence
good, 5% develop tonic clonic in adults
when does juvenile-myoclonic epilepsy set in and what happens in it
adolescence- adult. myoclonic but can have clonic and absences. learning unimpaired. remission unlikely
what is the most common syndrome and is it generalised or focal
rolandic- benign epilepsy with centro-temporal spikes. focal
what is benign epilepsy with centro temporal spikes (rolandic) and does it remit by adolescence
4-10 years. facial movements and strange movements of the lips. remits by adolescence
what AED can make absence and myoclonic seizures worse
carbamazepine
first line in tonic clonic
valproate, carbamazepine
first line in absence and myoclonic
valproate
first line in focal
carbamazepine, valproate, lamotrigine
second line tonic clonic
lamotrigine, topiramate
second line absence and myoclonic
lamotrigine
second line focal
topiramate, levetiracetem, gabapentin
other options other than AED for seizures
ketogenic diet, VNS, surgery
what is status epilepticus
> 30 mins of seizure. lorazepam IV if access, rectal diazepam/buccal midazolam if not. if no response- phenytoin
side effect valproate
weight gain, hair loss
side effect carbamazepine
rash, neutropenia, hyponatraemia, ataxia
side effect lamotrigine
rash. steven johnson
side effect benzos
sedation
side effect topiramate
weight loss, drowsy, withdrawal
how does an ataxic child present
abnormal gait, tremor
how would you describe the ataxic/cerebellar gait
broad based, staggering/lurching, fall towards side of cerebellar lesion
what is ataxia
inabillity to coordinate muscle activity- jerky and incoordination. inability to perform precise movements and loss of balance
what is true ataxia and what are the types
sign of cerebellar dysfunction. sensory and cerebellar
what is sensory ataxia
peripheral nerve or posterior columns damaged. wide based gait. can look normal whilst sitting, loss of position and vibration sense. positive romberg.
what is cerebellar ataxia
problem in the vermis of the cerebellum. lurching, staggering gait. unable to sit balanced
what viral infection is most implicated in ataxia
varicella
acute causes of ataxia
drugs, trauma, post infectious immune eg GBS, tumour, labyrinthitis
insidious ataxia
tumours, BPPV, hereditary- ataxia telangectasia, Friedrichs, congenital malformations- Dandy Walker, chiari malformation
how does hemiplegic gait look
flexed arm, straight leg, foot makes circle round0 circumduction, upper limb flexed, lower limb extended, distal more affected than proximal so get weak fingers and foot drop
what does diplegic gait look like
both arms flexed, both legs extended. tip toe walking. adduction prominent feature. can get scissoring gait
what is the gait in patient with myopathy
waddling gait- lean trunk away from side of lesion, compensate for the weak pelvic muscles which cant lift hip when lift leg to take a step
central causes of floppy baby
causes of developmental delay eg Downs, hypothyroid, hypocalcaemia, HIE, evolving CP
peripheral causes of floppy baby
spinal muscular atrophy, MG, myopathy
what is hydrocephalus
obstruction to the flow of CSF leading to dilatation of the ventricular system proximal to the site of obstruction.
where is the obstruction in non communicating hydrocephlus
within ventricular system or aqueduct
where is the obstruction in communicating hydrocephalus
arachnoid villi
causes of non communicating
aqueduct stenosis, dandy walker, chiari
causes of communicating
SAH, meningitis
signs hydrocephalus
bulging ant fontanelle, scalp veins distended, downward gaze or sun setting sign
what is needed for diagnosis neurofibramotosis type 1
2 or more of : 6 or more café au lait, more than one neurofibroam, axillary freckles, optic glioma, lisch nodule, bony lesions, first degree relative with NFM1
dominant feature of NFM2
acoustic neuroma
what are the lipid storage disorders causing neurodegeneration
tay sachs, gaucher, niemann pick
what enzyme is deficient in tay sachs
hexosaminidase A. auto somal recessive. Ashkenazi Jews. developmental regression. death by 2-5 years. cherry red spot macula
what enzyme is deficient in gaucher
beta glucosidase. Ashkenazi jews. splenomegaly, bone marrow suppression.
what enzyme is deficient in niemann pick
sphingomyelinase. death by 4 years. feeding difficulties, failure to thrive, cherry red spot macula
