Mark says: ‘I have had an ECG, EGG, MRI, CT, Tilt Table, 24 water sample, blood test, a scan on my heart. All these have come back clear... so the Neurologist came back and said I have NEAD and that I will have to see a Psychotherapist.’
How are non-epileptic attacks diagnosed?
- Electrocardiogram (ECG or EKG): This is a test which measures the electrical activity produced by the heart. The test is useful if your doctor thinks that your blackouts could be caused by an abnormal heart rhythm. Having an ECG involves wires being attached to the chest, arms and legs. A brief ECG can be recorded in less than 15 minutes. However, the ECG can also be recorded for longer periods of time with portable ECG devices. There are even small ECG recorders which can be implanted under the skin and which can record the ECG for many months.
- Electroencephalogram (EEG): This is a test which measures the electrical activity produced by the brain. It can show abnormal patterns of electrical activity or epileptic activity. Epileptic activity is seen during epileptic seizures but can sometimes also be seen in between seizures (without causing any symptoms). The EEG is recorded using small metal plates which are stuck to the head. A typical EEG recording involves recording the electrical activity of the brain at rest but also when the brain is stimulated, for instance by deliberate over breathing or with flashing lights. A brief recording can be completed in about 30 minutes. However, EEG recordings with portable machines over one or two days are also possible. It is important to realise that subtle EEG abnormalities without symptoms are common in healthy individuals and do not prove a diagnosis of epilepsy.
- Computed Tomography (CT) of the head: This is a test which produces a series of two dimensional pictures of the brain using X-rays. It can show up abnormalities of the shape or structure of the brain which could give rise to epileptic seizures. Having a CT involves lying down on a bench and putting your head into a large, open ring. It takes less than 15 minutes to take the pictures. It is important to realise that an abnormality on a CT scan does not prove a diagnosis of epilepsy.
- Magnetic Resonance Imaging (MRI) of the head: This is a test which produces very detailed pictures of the brain using radio waves. An MRI scan may be carried out to look for changes in the brain which can cause epilepsy. To obtain an MRI scan, the whole body has to go into a big machine (which looks and sounds a bit like an oversized washing machine). It takes about 40 minutes to acquire the pictures. Some people who get anxious in confined spaces struggle with MRI scans. Looking at the scanner first, listening to music over headphones, or taking tablets to help with anxiety just before the test can help. An abnormal MRI scan does not prove the diagnosis of epilepsy.
- Blood tests (Prolactin, Creatine Kinase): If blood can be taken soon after a seizure some constituents of the blood can give doctors a better idea whether a blackout was cause by an epileptic seizure or a nonepileptic attack.
- Tilt table test: This test can be useful if your doctor suspects that your attacks could be due to a sudden drop of blood pressure. The test involves people lying on a couch whilst their heart rate and blood pressure are constantly monitored. People who are prone to fainting may experience a drop in their blood pressure when the couch is tilted up 45 degrees. Unfortunately, a normal tilt table test does not rule out a diagnosis of fainting.
- Video-EEG monitoring: The most reliable test is video-EEG monitoring. It usually involves an admission to hospital. During this test people are constantly monitored with a video camera whilst their EEG is recorded. The aim of this test is to record a typical attack and the electrical brain activity during the attack. This test shows your doctor what exactly your attacks look like and whether the attacks are caused by epileptic activity in the brain. If you have NEAD, your attacks will not be associated by epileptic activity. Using this test, your doctor can make a diagnosis of NEA with almost complete certainty. However, sometimes NEAs cannot be proven by video-EEG because seizures are too infrequent or fail to occur in hospital. Also, even if a NEA has been recorded by video-EEG, this does not prove that all previous seizures were also NEAs. Having said that, studies using prolonged video-EEG monitoring have found that only one in twenty people with NEAD has additional epileptic seizures.