Seizure ?? Epilepsy??
A seizure is a paroxysmal event characterized by abnormal,
excessive, hypersynchronous discharge of cortical neuron
activity.
Epilepsy can be defined as a chronic seizure disorder or group
of disorders characterized by seizures that usually recur
unpredictably in the absence of a consistent provoking factor.
Epilepsy is not contagious
it is not a mental illness
or a cognitive disability.
The neurological dysfunction seen in epilepsy can :
begin at birth
childhood
adolescence or
even in adulthood
CLASSIFICATION
I. Partial seizures
A. Simple seizures - happens when unusual electrical activity
affects a small area of the brain
(without impairment of consciousness)
1. With motor symptoms
2. With special sensory or somatosensory symptoms
3. With psychic symptoms
B. Complex seizures -
(with impairment of consciousness)
1. Simple partial onset followed by impairment of
consciousness
2. Impaired consciousness at onset
C. Secondarily generalized
(partial onset evolving to generalized tonic-clonic seizures)
II. Generalized seizures
A. Absence - Causes you to blank out or stare into space for a few
seconds
B. Myoclonic - uncontrollable, lightning-fast muscle movements
C. Tonic - Muscles in the body become stiff
D. Tonic-clonic - involve both tonic (stiffening) and clonic (twitching or
jerking) phases of muscle activity
E.Atonic - Muscles in the body relax
F. Infantile spasms -
III.Status epilepticus - A seizure that lasts longer than 5
minutes, or having more than 1 seizure within a 5 minutes
period, without returning to a normal level of consciousness
between episodes
PARTIAL SEIZURES:
Common, 80% patients
simple partial seizures:
do not cause loss of consciousness
Signs &symptoms:
motor – convulsive jerking, chewing
motions, lip smacking
Sensory &somatosensory –
paresthesias(numbness on or just
underneath your skin)
Automatic – sweating, flushing, pupil
dilation
Behavioural – hallucinations, dysphasia,
impaired consciousness (rare).
complex partial seizures:
impairment of consciousness
purposeless behaviour is common
affected person may wander about aimlessly
aggressive behaviour (violence)
automatism
visual, auditory, or olfactory hallucinations
GENERALIZED SEIZURES:
Affecting both hemispheres
Diffuse
3 types:
1) Idiopathic epilepsies
• Age related
• Genetic origin
2) Symptomatic epilepsies
• A consequence of a known/suspected underlying
disorder of CNS
3) Cryptogenic epilepsies
• Disorder of a hidden course
• Age related
ABSENCE SEIZURES (petit mal)
Alterations of conciousness (absence) lasting 10-30sec
Staring (with occ. eye blinking) &loss in postural tone
10 or more daily
Onset occurs from 3-16yrs, disappear by 40yrs.
MYOCLONIC:
sudden, Involuntary jerking of facial, limb or trunk
muscles, in rhythmic manner
CLONIC:
Sustained muscle contractions alternating with relaxations
TONIC:
Sustained muscle stiffening
TONIC-CLONIC (grand mal) :
Sudden loss of consciousness
Tonic phase:
Patient become rigid &falls to the ground
Respiration is interrupted
Back arches
Lasts about 1min
Clonic phase:
Rapid muscle jerking Muscle flaccidity
Tongue biting,
tachy cardia, heavy salvation
During postictal phase:
Head ache, confusion, nausea, drowsiness, disorientation
May last for hours
ATONIC (drop attacks):
Sudden loss of postural tone, pt falls to the ground
Occur primarily in children
STATUS EPILEPTICUS:
Seizure occur repeatedly with no recovery
of consciousness b/w attacks
CAUSES
High fever, especially in infants
Drug use, alcohol withdrawal
Near-drowning or lack of oxygen from another cause
Metabolic disturbances
Head trauma
Brain tumor, infection, stroke
Complication of diabetes or pregnancy
Causes of epilepsy
Stroke Metabolic problems
Brain tumor Other neurological conditions
Brain infection
High fever, especially in infants
Past head injury
Drug use, alcohol Genetic factors
withdrawal
Epilepsy may occur
Developmental disabilities epilepsy do not have
Autism other impairments
Cognitive impairments and live very normal
lives.
PATHOPHYSIOLOGY
Paroxysmal discharges in cortical neurons
Aseizure orignates from grey matter of any cortical or subcorticalarea
Abnormal firing of neurons
Breakdown of normal membrane conductance &inhibitory synaptic
currents
Locally widely
Partial seizure Generalized seizure
•Abnormality of Potassium conductance
•Defect in voltage sensitive ion channels
•Deficiency in membrane ATPase
Neurone membrane instability
seizures
Deficiency of inhibitory neurotransmitters
Increase in excitatory neurotransmitters
promotes
Abnormal neuronal acitvity
Seizure
DIAGNOSIS
• Electroencephalogram (EEG)
•Neurological imaging studies
*Magnetic Resonance Imaging
(MRI)
*Functional MRI (fMRI)
*Computed Tomography (CT)
*Positron emission tomography
(PET)
*Single-photon emission
computerized tomography
(SPECT)
