2. • It is a chronic neurologic disorder manifesting by repeated
epileptic seizures (attacks or fits) which result from paroxysmal
uncontrolled discharges of neurons within the central nervous
system (grey matter disease).
• Seizure (Convulsion)
• Clinical manifestation of
synchronized electrical
discharges of neurons
• Epilepsy
• Present when 2 or more
unprovoked seizures occur at
an interval greater than 24 hours apart
3. Pathophysiology:
• Still unknown
• Some proposals:
– Excitatory glutamatergic synapses
– Excitatory amino acid neurotransmitter (glutamate, aspartate)
– Abnormal tissues — tumour, AVM, dead area (These regions of the brain
may promote development of novel hyper excitable synapses that can cause
seizures)
– Genetic factors (At least 20 %)
– Role of substantia nigra (Studies with 2-deoxyglucose indicate that a marked
increase in metabolic activity in SN is a common feature of several types of
generalized seizures; it is possible that some of this increased activity is
associated with GABAergic nerve terminals that become activated in an
attempt to suppress seizure spread. Because GABA has been shown to
inhibit nigral efferents, it is likely that GABA terminals inhibit nigral
projections that are permissive or facilitative to seizure propagation ) and
GABA
4. I. Generalised seizures
1. Generalised tonic-clonic
seizures (GTCS, major
epilepsy, grand mal):
It is most commonest
one , lasts 1–2 min.
The usual sequence is
aura cry
unconsciousness tonic
spasm of all body
muscles clonic jerking
followed by prolonged
sleep and depression
of all CNS functions.
Classification of seizures
5. 2. Absence seizures (minor epilepsy, petit mal):
• It Prévalent in children, lasts about 1/2 min.
• Momentary loss of consciousness, patient apparently freezes
and stares in one direction, no muscular component or little
bilateral jerking. EEG shows characteristic 3 cycles per
second spike and wave pattern.
3. Atonic seizures (Akinetic epilepsy):
• Unconsciousness with relaxation of all muscles due to
excessive inhibitory discharges. Patient may fall.
.
6. 4. Myoclonic seizures:
Shock-like momentary contraction of muscles of a limb or the whole body.
5. Infantile spasms (Hypsarrhythmia):
• It is mostly Seen in infants.
• Probably not a form of epilepsy.
• Intermittent muscle spasm and progressive mental eterioration.
• Diffuse changes in the inter seizure EEG are noted
II. Partial seizures
1. Simple partial seizures (SPS, cortical focal epilepsy):
• lasts 1/2–1 min. Often secondary.
• Convulsions are confined to a group of muscles or localized sensory
disturbance depending on the area of cortex involved in the seizure, without
loss of consciousness.
7. 2. Complex partial seizures (CPS, temporal lobe epilepsy,
psychomotor):
• attacks of confused behaviour and purposeless movements, emotional
changes lasting 1–2 min along with impairment of consciousness.
• The seizure focus is located in the temporal lobe.
III. Status Epilepticus:
It is continuous or recurrent seizures of an variety without recovery
of consciousness between the attacks
8. Signs & Symptoms:
• Whole body: fainting or fatigue
• Muscular: rhythmic muscle contractions or muscle spasms
• Cognitive: amnesia or mental confusion
• Psychological: depression or fear
• Also common: anxiety, blank stare, headache, sleepiness, staring spells, or
temporary paralysis after a seizure
9. Causes:
Epilepsy has no identifiable cause in about half of those with the condition. In the
other, condition may be traced to various factors.
Genetic influence. Some types of epilepsy, which are categorized by the type of seizure
you experience or the part of the brain that is affected, run in families. In these cases,
it's likely that there's a genetic influence. Researchers have linked some types of
epilepsy to specific genes, though it's estimated that up to 500 genes could be tied to
the condition. For most people, genes are only part of the cause of epilepsy. Certain
genes may make a person more sensitive to environmental conditions that trigger
seizures.
Head trauma.
Head trauma as a result of a car accident or other traumatic injury can cause epilepsy.
Brain conditions. Brain conditions that cause damage to the brain, such as brain
tumours or strokes, can cause epilepsy. Stroke is a leading cause of epilepsy in adults
older than age 35.
Infectious diseases. Infectious diseases, such as meningitis, AIDS and viral
encephalitis, can cause epilepsy.
Prenatal injury. Before birth, babies are sensitive to brain damage that could be caused
by several factors, such as an infection in the mother, poor nutrition or oxygen
deficiencies. This brain damage can result in epilepsy or cerebral palsy.
Developmental disorders. Epilepsy can sometimes be associated with developmental
10. Risk factors
Certain factors may increase your risk of epilepsy.
Age. The onset of epilepsy is most common during early childhood and after age
60, but the condition can occur at any age.
Family history. If you have a family history of epilepsy, you may be at an
increased risk of developing a seizure disorder.
Head injuries. Head injuries are responsible for some cases of epilepsy. You can
reduce your risk by wearing a seat belt while riding in a car and by wearing a
helmet while bicycling, skiing, riding a motorcycle or engaging in other
activities with a high risk of head injury.
Stroke and other vascular diseases. Stroke and other blood vessel (vascular)
diseases can lead to brain damage that may trigger epilepsy. You can take a
number of steps to reduce your risk of these diseases, including limiting your
intake of alcohol and avoiding cigarettes, eating a healthy diet, and exercising
regularly.
Dementia. Dementia can increase the risk of epilepsy in older adults.
Brain infections. Infections such as meningitis, which causes inflammation in
your brain or spinal cord, can increase your risk.
Seizures in childhood. High fevers in childhood can sometimes be associated
with seizures. Children who have seizures due to high fevers generally won't
develop epilepsy, although the risk is higher if they have a long seizure, other
nervous system conditions or a family history of epilepsy.
11. Differential Diagnosis
• History (from patient and witness)
• Physical examination
• Routine investigation: Haematology, biochemistry (electrolytes, urea
and calcium), chest X-ray, electroencephalogram (EEG).
Neuroimaging (CT/MRI) should be performed in all persons aged 25 or
more presenting with first seizure and in those pts. with focal epilepsy
irrespective of age.
• Specialised neurophysiological investigations: Sleep deprived EEG,
video-EEG monitoring.
• Advanced investigations (in pts. with intractable focal epilepsy where
surgery is considered): Neuropsychology, Semiinvasive or invasive EEG
recordings, MR Spectroscopy, Positron emission tomography (PET) and
ictal Single photon emission computed tomography (SPECT)