A good description of the event is the most important part of evaluation because in a case of seizure, physical findings are rare and diagnostic tests may not be conclusive. Following should be specifically enquired into:

(a) Whether a known case of seizure disorder. If yes, then

- whether on treatment (drug, dose and compliance).

- Type of seizures in the past

- Frequency of seizures

(b) Whether seizure was witnessed by anyone (or the patient was just found unconscious)

(c) Time of the day: seizures in early morning hours and during early phase of sleep are common in childhood epilepsy.

(d) Mode of onset

(e) History of fall

(f) Details of aura, if any: Most common is epigastric discomfort and a feeling of fear

(g) Details of involuntary movement: part involved (generalized/ focal), progression, type of movement (tonic/ clonic /tonic-clonic/ myoclonic).

Often, parents/witness can enact or re-create the event. The physical portrayal by the patent/witness is surprisingly similar to actual convulsion and is more accurate than verbal description.

Description of seizures along with family history may give clue to the possibility of genetic epileptic syndrome, e.g., autosomal dominant nocturnal frontal lobe epilepsy, partial seizures with auditory symptoms, etc.

(h) Any tongue bite/ frothing/ loss of sphincter control

(i) Any inciting event: trauma/ fever/ missed dose of anti-convulsant in a known case.

(j) Duration of convulsion

(k) Associated automatism/ behavioral abnormalities

(l) Associated symptoms: fever, ear discharge, headache, vertigo, etc.

In retrospect, irritability, mood swings, headache and subtle personality changes may precede a seizure by several days. Some parents can accurately predict timing of next seizure on the basis of change in disposition. However, a prolonged personality change or intellectual deterioration may suggest degenerative disease of CNS.

Associated constitutional symptoms like vomiting, failure to thrive, etc. suggest primary metabolic disorder or a structural lesion.

(m) Details of post-ictal phase

Past history of similar episode: Two unprovoked seizures more than 24 hours apart suggest seizure disorder and carry high risk of recurrences, if untreated.

History suggestive of prior neurological disease should be sought.

This is important for clues to etiology of seizures.

Family history of seizure disorder/ other neurological disease should be enquired into.

Of particular importance is:

Adequacy of airway, ventilation and circulation

Vital signs

Any evidence of head trauma: May be cause/ effect of seizure

Any evidence of ingestion of drug of abuse or other toxin

Any neurodeficit: Even subtle signs like hyperreflexia, subtle hemiparesis, equivocal Babinski’s sign should be looked for. If present, whether it resolves or persists beyond 24-48 hours. If it persists, it may suggest a contra-lateral hemispheric structural lesion such as a slow-growing temporal lobe glioma, as the cause of seizure disorder. Unilateral growth arrest of a thumbnail, hand or extremity in a child with a focal seizure suggests a chronic condition such as a porencephalic cyst, arteriovenous malformation or cortical atrophy of the opposite hemisphere.

Any sign of meningeal irritation: Specially look for these in case of seizures with fever.

Any evidence of raised intracranial tension

Any evidence of underlying degenerative/ metabolic/ congenital disorder

Any sign of neurocutaneous syndrome: Café-au-lait spots, ash-leaf macule, sebaceous adenoma, shagreen patch, neurofibroma, etc.

Ophthalmologic exam: Especially to look for any evidence of papilledema, chorioretinitis, retinal hemorrhages, coloboma and macular changes.

Conditions mimicking sezures : Based on the information gained by history and clinical examination, a few conditions closely mimicking seizures may be diagnosed and no further investigations may be required:

          1. Dystonic reaction/ extra-pyramidal syndrome

CT scan is a better modality to demonstrate intracranial calcification.

Scenario-5 A 7-year old known case of seizure disorder on anti-convulsants

A careful history is most important to search for the reason for break-through seizure. Serum anti-convulsant level should be or

 

Scenario-6 7-year old child presenting with status epilepticus

Following investigations should be done urgent basis, as soon as practically feasible:

Scenario-7 (rare) 7-year old child with seizures refractory to anti-convulsants

Such patients almost always have underlying anatomical defect in brain (epileptogenic focus). All the investigations as done for status epilepticus (Scenario-6 above) are indicated. In cases where epilepsy surgery is being contemplated, following investigations have their role to play:

It is a sensitive and inexpensive technique to study regional blood flow. In cases of seizure disorder, it is used to identify perfusion in ictal and interictal states. Increased perfusion in the ictal phase is suggestive of epileptiform focus. It has become an important pre-surgical investigation of intractable epilepsies.

-Dr. Puneet Kumar