• an episodic disturbance

• that may or may not be preceded by a warning (aura)

• brief in duration

• unpredictable, with

1. Confirm that the patient has suffered a seizure.

2. Characterise the type(s) of seizure(s).

3. Assess the frequency of seizures.

4. Identify any precipitating causes.

5. Establish the aetiology.

6. Decide whether to treat or not.

7. Choose the appropriate drug and dose and monitor the response to therapy.

8. Advise regarding lifestyle.

9. Consider surgery in patients who fail to respond to drug therapy.

10. Decide whether and when to withdraw therapy in ‘seizure-free’ patients.

Useful questions to ask the patient

Useful questions to ask an eyewitness or relative

Some patients can suffer unrecognised seizures for many years [9], particularly children and teenagers who are often thought to be daydreaming. Relatives may have witnessed a number of episodes and not recognised them as seizures.A useful sequence of questions includes:

Keep asking this question until the whole episode has been described in detail. More specific questions include:

It is often useful to question more than one eyewitness or relative as one individual may not have observed all the details. When seeing a patient with suspected epilepsy or a seizure, more is to be gained by picking up the telephone and ringing a family member or an eyewitness than undertaking investigations.

Epilepsy in the elderly

It is a common misconception that epilepsy is a disease of childhood. While this is largely true of absence (petit-mal) seizures, which are very rare in adults and often present when they do occur with absence status epilepsy, seizures do occur in the elderly and the incidence increases with increasing age, as shown in Figure 8.1. Elderly patients with epilepsy most often present with tonic–clonic or complex–partial seizures that have a higher recurrence rate than in the younger population. The complex–partial seizures are often difficult to diagnose since they present with atypical symptoms, particularly prolonged post-ictal symptoms including memory lapses, confusion, altered mental status and inattention [10].

Although there is a continuing incidence of seizures throughout life, they are more common in the first 5 years. There is also a higher incidence in the 70- to 80-year-old age group [11].

• tonic–clonic

• absence

• complex–partial.

• simple–partial

• myoclonic

• clonic

• tonic

• atonic

• benign rolandic seizures.

1. seizures that cause the patient to fall with or without loss of consciousness (see Figure 8.2)

2. seizures that are not associated with a fall with or without loss of consciousness (awareness; see Figure 8.3).

Tonic–clonic seizures

Tonic seizures

Although these can occur at any age they are most commonly seen in childhood. When an adult has what seems like a tonic seizure it is often secondary to a hypotensive episode, e.g. vasovagal or neurocardiogenic syncope. Tonic contractions affect the face and limbs, resulting in flexion of the upper limbs and trunk and either flexion or extension of the lower limbs. Although consciousness is impaired, these seizures are very brief often lasting only seconds. It is rare for these to occur in isolation and usually patients have other types of seizures.

Atonic seizures

Atonic seizures, also referred to as drop attacks, are rare and consist of a sudden loss of postural tone: if brief only the head may drop, but if more severe the person will fall to the floor, often sustaining injury. There may be a brief period (seconds) of impaired consciousness but no post-ictal confusion. Patients usually have other seizure types, including a few brief myoclonic jerks, prior to the atonic seizure but most often tonic–clonic epilepsy.

Drop attacks due to epilepsy mainly occur in childhood; drop attacks that occur in elderly adults are thought not to be epileptic in origin and are discussed in Chapter 7, ‘Episodic disturbances of function’. The Lennox–Gastaut syndrome is seen in childhood and consists of multiple seizure types including atypical absence seizures, myoclonic, tonic–clonic and atonic seizures with often a degree of intellectual disability [5].

Myoclonic seizures

Myoclonus is a shock-like contraction of a muscle or a group of muscles. Myoclonus occurs in people without epilepsy, often when they are just falling asleep but also occasionally any time of the day. The frequency would usually be less than once a month. There is also an entity called segmental myoclonus that is not a seizure disorder, where a particular muscle or group of muscles supplied by a particular nerve or nerve root will have myoclonic jerks.

In patients with myoclonic epilepsy, these myoclonic jerks are more frequent, often occur during sleep but characteristically occur first thing in the morning on awakening. They affect the whole body or a single limb and may be single or repetitive jerks. In myoclonic seizures the patient is fully aware of what is happening. There is no aura, loss of awareness or post-ictal confusion, i.e. the patient is normal immediately before and after the event. Myoclonus induced by movement is a feature of post-hypoxic myoclonus [15].

Complex–partial seizures

Complex–partial seizures most commonly arise from the temporal lobe in association with mesial temporal sclerosis. Complex–partial epilepsy (CPE) was originally referred to as temporal lobe epilepsy. However, the recognition that minor seizures that impair consciousness without causing the patient to fall may arise from the occipital, frontal or parietal lobes has led to the use of the term CPE.

Absence (petit-mal) seizures

Absence epilepsy generally occurs in childhood and is very rare as a primary presentation in adults. In retrospect, however, when one takes a careful history from a patient with their first tonic–clonic seizure, many patients have had unrecognised absence seizures [9] in childhood and have simply been regarded as either dull or a daydreamer.

It is surprising how many absence seizures patients can experience without people actually noticing them because they are so brief. Absence seizures can readily be induced by hyperventilation (HV). In one study of 47 children with childhood absence seizures, HV induced seizures in 83% (39/47) of children. Of the eight children who did not have seizures induced by HV, four were too young to perform HV. In the other four children, HV was performed but may not have been performed well [19].

The important clue that helps differentiate absence seizures from daydreaming is that with absence seizures the patient will interrupt their behaviour. For example, they will momentarily pause unexpectedly during a conversation or a game they have been playing, and then appear to resume it as if nothing has happened. Many children daydream or are concentrating on television or some other activity and, although it can be difficult to attract their attention, they are not unresponsive. One common presentation of absence epilepsy is the child who has previously done well at school and who begins to fail. Unfortunately, many children in the past were assumed to be daydreamers who were not working hard enough when in fact they were missing large parts of the lesson because of minor absence seizures. In the author’s experience, many teachers fail to detect children with minor epilepsy. It is when these children who fail have further teaching that the seizures are actually discovered by the tutor who spends more time with them on a one-to-one basis.

The EEG in absence seizures shows a characteristic 3 per second spike and wave (see Figure 8.4).

Simple partial seizures

The essential characteristic of simple partial seizures is that they can occur at any age in either sex and consist of a brief stereotyped sensation without loss of awareness, i.e. the patient is fully conscious of what is happening and is able to describe the whole episode from start to finish. There is no warning or aura, nor is there any post-ictal drowsiness or confusion. Examples of this type of epilepsy are patients who experience a tingling sensation that may commence in their feet and rise up to the top of the head and sometimes go back down again to their feet, over a matter of seconds.

Focal motor seizures

These episodes are very brief, usually lasting less than a minute or two, although they can go on repetitively in patients, in which case the term focal motor status epilepsy is used. The patient is fully aware of what is going on around them, there is usually no warning and certainly there is no post-ictal drowsiness or confusion. The seizures consist of repetitive contractions down one side of the body.