Paed:Neuro Flashcards
(104 cards)
What is a seizure?
A sudden disturbance of neurological function caused by an abnormal or excessive. neuronal discharge. Can be epileptic or non-epileptic.
What can cause epilepsy?
idiopathic secondary to cerebral dysgeneis, cerebral vascular occlusion, cerebral damage cerebral tumour neurodegenerative disorder neurocutaneous syndromes
What can cause a non-epileptic seizure?
Febrile seizures Metabolic: hypoglycaemia, hypocalcaemia, hypomagnesia, hypo/ernatraemia Head trauma Meningitis/encephalitis Poisons/toxins
What is a febrile seizure?
Seizure + fever, without intracranial infection due to bacterial meningitis or viral encephalitis.
How does a febrile seizure present?
Brief, generalised tonic-clonic seizures
Occurs in early viral infection when temperature is rising rapidly
Does NOT cause brain damage
*treat underlying infection
Explain paroxysmal disorders/funny turns
Breath-holding episodes: toddler precipitated by anger, holds breath, goes blue then limp and rapid recovery
Reflex anoxic seizures: toddler precipitated by pain, tops breathing, goes pale, brief seizure then rapid recovery
What is epilepsy?
Chronic neurological disorder characterised by recurrent unprovoked seizures consisting of transient signs associated with abnormal, excessive or synchronous neuronal activity in the brain.
What is a generalised seizure?
Discharge from both hemispheres (absence, myoclonic, tonic, tonic-clonic or atonic)
Focal
Seizures arise from one (or part of one) hemisphere
Clinical presentation of frontal focal seizure?
Motor cortex
Clonic movements including Jacksonian march
Asymmetrical tonic seizures
Atonic seizures from messiah frontal discharge
Clinical presentation of temporal focal seizure?
Most common
Auditory or sensory phenomena
Lip smakcing
De ja vu
Clinical presentation of occipital focal seizure?
Positive/negative visual phenomena
Clinical presentation of parietal focal seizure?
Contralateral altered sensation sensation (dysaesthesia)
Describe a generalised seizure
always LOC
no warning
symmetrical seizure
bilaterally synchronous seizure discharge on leg or varying asymmetry
Describe an absence seizure
Transient LOC with abrupt onset and termination, unaccompanied by motor phenomena except for some flickering of the eyelids and minor alteration in muscle tone.
Absences may be typical (petit Mal) or atypical
Often precipitated by hyperventilation
Describe a myoclonic seizure
Brief, often repetitive, jerking movements of the limbs, neck or trunk
Non-epileptic myoclonic movements are also seen physiologically in hiccoughs (myoclonus of the diaphragm( or on passing through stage II sleep (sleep myoclonus)
Describe a tonic seizure
Generalised increase in tone
Describe a tonic-clonic seziure
Rhythmical contraction of muscle groups following the tonic phase
Rigid tonic phase: children may fall to ground, stop breathing and become cyanose.
Followed by the clonic phase, with jerking of the limbs.
Irregular breathing, cyanosis persists + saliva may accumulate in the mouth.
May be biting of tongue and incontience of urine
Lasts seconds to minutes followed by unconsciouness or deep sleep for several hours
Describe an atonic seizure
Often combined with a myoclonic jerk, followed by a transient loss of muscle tone causing a sudden fall to the floor or drop of the head.
How is epilepsy diagnosed?
- Detailed history including eyewitness account
- EEG: 3Hz spike
- MRI + CT structural brain scan (identify tumour, vascular lesion and sclerosis)
- Functional scans: PET, SPECT to find areas of hyper metabolism in epileptogenic lesions.
- Metabolic Ix: na+ and glucose
How is epilepsy managed?
Buccal benzos?
Generalised seizures: valproate + lamotrigene
Focal seizures: carbamazepine, lamotrigene
Last resort: phenytoin
What is West syndrome?
4-6months Violent flexor spasms of head, trunk and limbs followed by extension of arms Often occurs on walking many times a day EEG: hypsarrhtmia Tx: vigabatrin or corticosteroids Often develop LD or epilepsy
What is Lennox-gastaut syndrome?
1-3 years
multiple seizure types but mostly drop attacks (Astatic seizures), tonic seizures and atypical absences
- complex neurological problems
Explain childhood absence epilepsy?
4-12 years
Stare momentarily and stop moving only for a few seconds
Child has no recall, can interfere with schooling.
Induced by hyperventilation (child asked to blow on windmill for 2-3mins in OP clinic)
EEG: 3Hz spike, bilaterally synchronous