Classification of epileptic seizures

Epileptic seizure is a symptom of epilepsy; and can also occur in number of diseases.

The type os seizure is determined by: patient history (anamnéza), observation, EEG
Determining the type of seizure can help in localising the epilepsy in the central nervous system, to search for ethology of the seizure imaging methods are used.
Primary epilepsy – It has a strong genetic predisposition, with no underlying structural, metabolic or pathological abnormality. There are no deviations from the norm in the period between seizures.
Secondary (symptomatic) epilepsy – This type is accompanied by other CNS diseases, prognosis for secondary epilepsy is worse than primary epilepsy^[1]

Partial epileptic seizure (focal, non focal)[edit | edit source]

It is localization of the epileptic discharge, which can spread to the surroundings or can secondarily generalise; partial seizures are a manifestation of a localised (focal) brain lesion
always secondary (tumor, inflammation)^[1]

Partial simplex seizure[edit | edit source]

consciousness is preserved, but patient has symptoms:
- motor (tonic / clonic) – 1 limb segment, Jacksonian motor epilepsy, aversive seizures (from gyrus precentralis)
- sensory – pseudo-hallucinations, illusions, paresthesia, pain, Jackson's sensitive epilepsy (from the post-central gyrus and sensory cortex)
- autonomic – TF, DF, nausea, redness, pain
- psychological – dreamy state, deja vu, depersonalization (from the limbic system and cortex)^[1]

Partial seizure with complex symptomatology[edit | edit source]

consciousness impaired: (temporal epilepsy) – aura (uniform crisis, depersonalization, hallucinations / delusions, abdominal aura), seizure (absent gaze, stereotypic movements)
- loss of consciousness follows a partial simplex seizure
- loss of consciousness from the beginning^[1]

Partial seizure secondarily generalised[edit | edit source]

sensations → to brain → loss of consciousness → thalamocortical circuit → to both the hemispheres
prodrome → aura → ictus → postparoxysmal period
- partial simplex seizure with secondary generalisation
- complex partial seizure with secondary generalisation
- partial simplex to complex seizure with secondary generalisation^[1]

Generalised epileptic seizure[edit | edit source]

bilateral localised seizure, symmetrical without focal onset
the beginnings of epileptic discharges are localised in the meso-diencephalic reticular formation and radiate diffusely throughout the brain
with convulsions (convulsive) / without convulsions (non-convulsive)
disorder of conciousness seizure states without aura, primary and secondary
The typical course has 3 phases: Pre seizure period – aura (maybe absent); seizure itself, which can last for several minutes; then the patient falls asleep
- absence (petit mal): „shock“ (squinting, twitching eyelids), paleness / flushing, EEG: spike / slow waves
  - typical absence
  - atypical absence
- myoclonic seizures – fast twitch muscles. convulsions without loss of consciousness, EEG: spike discharge
- tonic seizure (West Syndrome) – tonic spasms of trunk and flexion of upper limb muscles and extension of lower limb muscles, in children, mental retardation and falls.
- clonic seizures (childhood and Janz's juvenile myoclonic epilepsy) – less frequency of twitches than myoclonus, loss of conciousness, children
- atonic seizure (astatic seizure, Lenox-Gastaut syndrome) – loss of postural muscle tone → sudden fall to the ground, may not be a disturbance of consciousness
- tonic-clonic seizure (grand mal) – loss of consciousness, fall cyanosis, salivation, pupillary areflexia, (1) tonic phase (EEG: high symmetrical spikes) → (2) tonic-clonic phase (↑BP, TF, tonic contractions and short relaxations, EEG: high slow waves / spikes and wave complexes) → (3) relaxation phase (muscle flaccidity and incontinence, EEG: isoelectric line) → awakening and confusion / sleep^[1]

Unclassified seizures[edit | edit source]

Status epilepticus[edit | edit source]

90 % of uncomplicated generalized seizures that last less than 2 minutes and rarely upto 5 minutes, i.e. it is necessary to treat each seizure lasting 5 or maximum 10 minutes as status epilepticus (SE).

Mortality of generalised tonic-clonic SE is 10–20 %.

consciousness is impaired between seizures → brain damage may occur
State of emergency! (exhaustion, ↑BP)^[1]
accompanied by fever, leukocytosis, acidosis and there is a risk of exhaustion and collapse of organism, cerebral hypoxia from respiratory hypoventilation and cerebral edema