Diagnosing epilepsy Dr Matthew Walker Dr Trisha Macnair Epilepsy may be diagnosed if a patient has had two or more 'unprovoked' seizures in one year - that is, not the immediate result of recreational drug use, alcohol or head injury.

Most people with seizures will be referred to a hospital specialist. To make a diagnosis, the doctor will try to work out:

• Has the patient definitely had a seizure?
• If so, are they likely to have more? (After two seizures, the chance of having more is 80 to 90 per cent)
• What is the underlying cause of the seizures?

Tests

When you arrive, the nurse running the clinic will ask you some simple questions and may do some basic tests, such as weighing you and measuring your height. They may also want to test a sample of urine, to check for things such as infections or abnormal levels of sugar.

You may then have to wait a little while to see the neurologist, who'll ask you many questions to try to find out more.

This will include questions about:

• Your symptoms
• Past illnesses like meningitis
• Any medication you're taking
• General health, such as sleep or diet
• The health of others in your family
• Lifestyle, such as smoking or drinking

Some questions may seem odd or irrelevant, but these can be helpful in ruling out other conditions or causes of seizure.

The neurologist will then want to examine you to check your heart and lungs, and particularly to examine your nervous system.

They may also order some painless tests. These include:

• EEG (electroencephalogram) - measures the electrical activity of the brain using about 20 pads placed on your head
• Brain scans - CT (computerised tomography) and MRI (magnetic resonance imaging) scans produce very clear pictures of your brain and are especially important to rule out a brain tumour, which is the cause of epilepsy in a few cases (but very rarely in absent seizures)
• Blood tests - may be needed to rule out certain causes of seizure
• Magnetic resonance imaging (MRI) - another imaging method, this time using a strong magnetic field and radio waves. It is gradually replacing CT as the investigation of choice, as it's much better at showing brain abnormalities.

These tests should give the neurologist a good idea of your condition. You may have to return to the clinic a week or two later for the results.

If the neurologist diagnoses epilepsy, it may be recommended you start taking anti-epileptic medication. You may also be given advice about possible changes you may need to make to your lifestyle.

Don't hesitate to ask about anything you don't understand or want to know more about. The more you know about your condition, the better you will be able to control it.

This article was last medically reviewed by Dr Trisha Macnair in January 2008.
First published in May 2002.