Seizures

Question 1

Seizures - def

Answer 1

Seizure = clinical expression of abnormal, excessive, synchronous discharges of neurons residing primarily in the cerebral cortex

Question 2

Seizures - types (two main categories)

Answer 2

A. Generalised
1. Myoclonic = with shock-like movement of one/several parts of the whole body
2. Tonic = with sustained contraction and stiffness
3. Clonic = with rhythmic jerking of one limb, one side, or all of the body
4. Tonic-clonic = combination of the above forms
5. Absence = episodes of abrupt psychomotor arrest lasting 5-15s in younger children, but can be longer in the older child. Can be associated with retropulsion of the head, upward deviation of the eyes and eyelid, or perioral myoclonia (note - facial myoclonia can be asymmetrical and give the impression of a focal seizure)
(Also atonic seizures = often have a myoclonic jerk, followed by transient loss of muscle tone causing a sudden fall to the floor or drop of the head)

B. Focal (4)

• Generally start in one area of the brain and then may spread, and ultimately generalise.
  1. Occipital = multicoloured bright lights spreading from one area of homonymous visual fields
  2. Centroparietal (parietal lobe = sensory) = sensorimotor phenomena spreading from one limb and marching up one side of the body
  3. Temporal (temporal lobe = visual memories, language comprehension and emotion association) = gastric discomfort, anxiety, memory disturbances (e.g. deja vu - familiarity), autonomia (e.g. automatisms such as nose rubbing), contralateral clonic or dystonic movements (dystonia = abnormal muscle tone leading to involuntary spasm and abnormal posture)
  4. Frontal = dystonic posturing and strange guttural noises

Question 3

Seizures - mx (first unprovoked seizure)

Answer 3

Note: about 50% of patients experiencing their first seizure will never have another and therefore do not require treatment

1. First aid
   - Tonic clonic (5) = time the seizure, remove hard objects from area, place something soft under head, roll person to side, call ambulance
   - Focal seizures (3) = guide person past obstacles and away from danger, calmly talk with the person and reassure them as they regain awareness, call ambulance
2. History = full account of phx, shx and fhx
3. Examination = thorough ex looking for markers of neurological disease, esp. skin and dysmorphism (difference of body structure)
4. EEG = looking for epileptiform abnormalities
5. Imaging = MRI not indicated after single seizure alone, but if an abnormality is found on physical examination, MRI is very important to exclude a SOL

Question 4

Seizure vs. syncope

Answer 4

1. Incontinence
   - Seizure = common
   - Syncope = possible but rare
2. Post-ictal
   - Seizure = occurs in tonic-clonic or complex partial
   - Syncope = no
3. Motor activity
   - Seizure = common
   - Syncope = occasional brief jerks
4. Injury
   - Seizure = common, tongue biting
   - Syncope = rare unless from fall
5. Aura
   - Seizure = possible specific aura
   - Syncope = light-headed sensation