Epilepsy: Types, Partial epilepsy, Generalized epilepsy, Diagnosis, and Treatment

 What is a Seizure?

A seizure is abnormal electrical activity in the brain or central nervous system result in abnormal motor, sensory, or psychomotor experiences. 

👉Every seizure is not epilepsy.

Seizure

Abnormal Motor Experiences

1. Tonic: Agonist and antagonist fire simultaneously. All the body stiffens.
2. Clonic: Agonist and antagonist fire alternatively. Jerky movement.
3. Tonic-Clonic:-First agonist and antagonist tonically fire than alternatively.
4. Atonic: Sudden electrical activity in motor area goes pathologically down and result in loose of tone.
5. Myotonic: Sudden single jerk recurrently happen.

Abnormal sensory Experiences

1. Somatic- abnormal electrical activity in sensory cortex.
2. Special- abnormal electrical activity in visual, auditory cortex.
3. Visceral- abnormal electrical activity in Insula.

Function of temporal lobe

1. Taste
2. Olfaction
3. Emotion
4. Sexual behaviour
5. Differentiate between fantasy and reality.

Function of Limbic System 

1. Memory
2. Primitive function (olfaction, taste)
3. Sexual behaviour
4. Emotional behaviour

👉👉The limbic system in Association with the temporal lobe is concerned with species survival and perpetuation.

Abnormal psychomotor experiences/Temporal lobe epilepsy

🤙Depends on which area of the temporal lobe is irritated.

• Gustatory hallucination 
• Over familiarity/jamais Vu 
• Olfactory hallucination 
• Sense of unreality/Déjà Vu 
• Sexual behaviour

What is Epilepsy?

Epilepsy is a tendency for spontaneous, recurrent seizures due to abnormal electrical activity in CNS.

Types of epilepsy-

1. Partial epilepsy

2. Generalized epilepsy

Partial Epilepsy

• Epilepsy in which the onset of a seizure is referable to one hemisphere (right or left hemisphere).
• Types of partial epilepsy

1. Simple partial epilepsy- no loss of consciousness.

1. Motor simple partial epilepsy

1. Tonic

2. Atonic

3. Clonic

4. Tonic-clonic

2. Sensory simple partial epilepsy

3. Psychomotor simple partial epilepsy

2. Complex partial epilepsy- with loss of  consciousness

1. Motor complex partial epilepsy

1. Tonic

2. Atonic

3. Clonic

4. Tonic-clonic

2. Sensory complex partial epilepsy

3. Psychomotor complex partial epilepsy

Generalized Epilepsy

Seizure attacks arise from one focal point and involve both hemispheres.

💸💸Always consciousness is impaired.

Types of Generalised Epilepsy-

1. Absences 

2. Myoclonic seizures

3. Clonic seizures

4. Tonic-Clonic seizures

5. Atonic seizures

Absences (Petit mal epilepsy)

1. Onset is childhood (between 4 to 12 years of age).
2. A brief episode of seizure in which a person is mentally absent.
3. Patients develop 100 attacks per day for 5 to 15 seconds.

4. 30% of children grow up (adolescence) may develop Tonic-clonic seizures (Grand mal epilepsy).

Myoclonic Seizures

1. Sudden, brief, generalized muscle contractions with loss of consciousness.
2. The commonest disorder is benign juvenile myoclonic epilepsy (JME).
3. Also occurs in degenerative and metabolic disease.

Tonic Seizures

1. Sudden sustained muscular contraction with immediate loss of consciousness.
2. In adults, tonic attacks are rare.

Tonic-Clonic Seizures (Grand Mal Epilepsy)

Phases of grand mal epilepsy:

1. Prodrome

1. Occurs before seizures.

2. Prodrome is not part of seizures.

3. During prodrome, Patients can develop mood abnormality and motor abnormality which is perceived by self but others can observe.

2. Aura

1. This is part of seizures and the earliest phase of seizures.

2. The only Patient can perceive a strong gut feeling, smell, taste.

3. Tonic phase:

1. Increase body tone with rapid loss of consciousness.

2. The patient may develop cyanosis and epileptic cry.

3. An epileptic cry is a result due to spasticity of respiratory muscles with partial closure of vocal cords.

4. Clonic phase:

1. The clonic phase begins as abnormal neural activity is slows.

2. Agonist and antagonist muscle fire alternatively result in jerking.

3. There may be a risk of tongue biting and urinary incontinence.

Atonic Seizures

A seizure is characterized by loss of muscle tone and sudden fall with the loss of consciousness.

Pseudo Seizures Pseudo Seizures are seizures like conditions by psychological which are not due to electrical discharge in CNS. Symptomatic Epilepsy Epilepsy which is occurs as symptoms of an underlying disease. Example: Meningitis, Brain tumors, Cerebral abscess. Jacksonian Epilepsy When involuntary movement 'march' from one muscle group to the next. This is because the electrical discharge in the cerebral cortex is 'marching'. It can be sensory or motor. Todd's Paralysis After the motor seizure, the affected limb may remain weak for some duration before the return of function.

🚵🚵Status Epilepticus

• When the consciousness does not return between the attacks of seizures, the condition is called status epilepticus.
• This state may be life-threatening with permanent damage, coma, development of pyrexia, and circulatory collapse.

Causes of Generalised Epilepsy

1. Genetics
2. Cerebral birth injury
3. Hydrocephalus
4. Prolonged anoxia
5. Drugs which irritate CNS:
1. Penicillin
2. Antimalarial drugs
3. Cardiac arrhythmic drugs
4. Cytotoxic drugs
6. Withdrawal of alcohol
7. Hypocalcemia
8. Renal failure
9. Meningitis
10. Syphilis
11. Degenerative diseases

Investigation

1. Hematology
2. Biochemical analysis (electrolytes, urea, and calcium)
3. Chest X-ray
4. Electroencephalogram (EEG)
5. CT scan
6. MRI
7. Positron emission tomography (PET) 
8. Single-photon emission computed tomography (SPECT)

Medical Management

• If the patient goes 3 years without an attack, withdrawal of therapy should be recommended.
  
• The commonest drugs used:
• Carbamazepine
• Sodium Valproate/valproic acid
• Phenytoin (chronically produce facial features and hirsutism (looks like man face)
• Phenobarbitone
• Lamotrigine
• Gabapentin
• Topiramate
• Tiagabine
• Zonisamide
• Oxcarbazepine
• Levetiracetam
• Lorazepam
• Diazepam
• Ethosuximide
• Clonazepam

👉The broadest anti-epileptic drug is Sodium Valproate.

Drugs for partial epilepsy

1st – Carbamazepine

2nd – sodium Valproate

Drugs for Tonic-clonic Generalised Epilepsy

1st – Sodium valproate

2nd – Lamotrigine

Drugs for Generalised Absence Epilepsy

1st – Ethosuximide

2nd – Sodium valproate

Drugs for Myoclonic Epilepsy

1st – Sodium valproate

2nd – Clonazepam

Drugs for Status Epilepticus

1st – Diazepam or Lorazepam

2nd – phenytoin or Fosphenytoin