Focal seizures

# Temporal lobe epilepsy

Epidemiology: most common form of epilepsy
- ∼ 40% of all epilepsy cases
- ∼ 70% of focal epilepsy cases
Etiology
- Hippocampal sclerosis: found in approx. 70% of patients suffering from temporal lobe epilepsy that is resistant to pharmacotherapy
  - Histopathology: atrophy of the hippocampal neurons with marked reactive gliosis (astrocyte proliferation in response to injury).
- Encephalitis (e.g., herpes simplex encephalitis)
- Developmental disorders
- Neurodegenerative disorders
- Tumors
Clinical features: Seizures commonly occur in clusters, last approx. 30 seconds to 2 minutes, and follow a specific sequence.
1. Aura
  - Visceral, olfactory, or auditory
  - Feelings of familiarity or unfamiliarity and “dreamy states”
2. Focal seizure with impaired awareness (complex partial seizure)
  - Motor symptoms
    - Typically oral alimentary automatisms (e.g., lip-smacking)
  - Autonomic symptoms
  - Altered mental status
    - Children appear absent-minded (e.g., staring ahead, unresponsive when spoken to)
    - No loss of consciousness
3. Postictal phase
  - Confusion and tiredness (common)
Diagnosis: EEG shows temporal lobe spikes