Epilepsy: Focal Flashcards
Definition
The recurrent tendency to spontaneous intermittent, abnormal electrical activity in part of the brain, manifesting in seizures
Seizure definition
Paroxysmal alteration of neurological function as a result of excessive, hypersynchronous discharge of neurons within the brain.
Reversible causes of seizures and features (VITAMIN DE)
Vascular
Infection
Trauma
Autoimmune - SLE
Metabolic
- hypoglycaemia,
- hyponatraemia,
- hypoxia
-alcohol withdrawal,
Idiopathic - EPILEPSY
Neoplasms
Dementia + Drugs (cocaine)
Eclampsia + everything else
- typically longer with closed eyes and mouth
- don’t occur during sleep and don’t involve incontinence or tongue biting
- pre-ictal anxiety symptoms in non-epileptic = they know what is about to happen
Epidemiology
< 20 or > 60
Inherited Risk factors
Premature birth
Brain development malformation
Genetic condition:
- Cerebral palsy: up to 30% have epilepsy
- Tuberous sclerosis
- Neurofibromatosis
- Metabolic disorders: e.g. lysosomal storage disorders
- Mitochondrial diseases: e.g. MELAS
Family history
Arterio-venous malformation
Acquired Risk Factors - think bad things that can happen to brain
Febrile convulsions as a child: particularly if complex
Traumatic brain injury
Neurodegenerative disease
Ischaemic stroke
Brain tumour
Intracerebral infection: meningitis, encephalitis, abscess
Illicit drug use: cocaine
Mixed Risk Factors
Dementia
Aetiology (STATIC)
Strokes
Tumour/space-occupying lesions
Alzheimer’s
Tremors from Alcohol withdrawal (Delirium tremors)
Idiopathic (MC)
Cortical scarring e.g. trauma, cerebrovascular disease, infection
Pathophysiology
The disrupted neurological function causing a seizure is the result of an imbalance between excitation and inhibition within the neurons of the brain.
Normal balance between GABA - and glutamate + shifts towards glutamate = more excitatory
Components of a seizure
PRODROME
- Precedes the seizures usually by hours/days
- Weird feeling e.g. mood/behaviour changes
AURA:
- Part of the seizure where the patient is aware + often precedes other manifestations
ICTAL:
- Length of seizure
- Appearance: jerking suggests tonic-clonic, behavioural arrest suggests absence
- Progression: e.g. jacksonian march - a phenomenon in which a seizure spreads from the distal part of the limb towards the face
- Consciousness
- Injury: tongue biting, head injury
- Urinary incontinence
POST-ICTAL:
- The period after a seizure
- Headache, confusion, myalgia, sore tongue (often bitten)
- Temporary weakness after focal seizure in motor cortex = post-ictal Todd’s palsy
Temporal lobe Signs
Oral automatism: lip smacking, chewing, swallowing
Manual automatisms: picking, fumbling
Automatic behaviour: running, walking
Auras (80%) : déjà vu, feeling of fear, unpleasant smells,
Auditory: buzzing, ringing, vertigo
Frontal lobe signs
Predominantly motor symptoms: pelvic thrusting, bicycling, tonic posturing
Jacksonian march = march up/down motor homunculus
Post-Ictal Todd’s palsy = starts distally in a limb and works its way upwards to the face
Sexual automatisms
Bizarre behaviour
Vocalisations
Parietal lobe signs
Parasthesias
Visual hallucinations
Visual illusions
More subjective and difficult to diagnose than other areas
Occipital lobe signs
Visual hallucinations
Transient blindness
Rapid and forced blinking
Movement of head or eyes to the opposite side
Epilepsy sensitive signs
Tongue biting
Head turning
Muscle pain
LOC- Post ictal symptoms
Cyanosis
