Epilepsy
Diagnosing epilepsy
Many people experience a single isolated seizure at some point in their lives, and a seizure may occur from causes unrelated to epilepsy.
If a person has more than one epileptic seizure, or if tests show that a person is at risk of further seizures occurring, then a diagnosis of epilepsy is usually considered.
A person is diagnosed as having epilepsy if they are at risk of experiencing or have a tendency to experience repeated spontaneous or unprovoked seizures that start in the brain.
Going to the doctor after a first seizure
A person who has had a seizure might not remember what actually happened, so it helps to have information or a description of what happened from someone who witnessed the seizure.
When visiting the doctor, details of what happened before, during, and after the seizure can be very important in making a diagnosis. If the GP feels that epilepsy is a possibility, the person will be referred to a specialist, usually a neurologist.
A neurologist will usually arrange medical investigations (which may not be conclusive) and will consider other possible causes for the seizure(s).
Describes what happens during and after a seizure.
Describes what happens during and after a seizure.
Well sometimes it's just my speech that gets distorted, a bit like when I was in the neurologist's office. Because thinking back, before I had the first episode that made me go to the GP, I had had a couple of times when I was talking on the telephone to people and the wrong words came out. And at one point the person on the other end of the phone - he knew me quite well - said 'You're talking gobbledygook' basically. And I think if he hadn't known me he might have thought I was drunk or something, it was that sort of, sort of slurred speech and not quite the right words. And so sometimes my speech gets distorted. Sometimes I get a bit tongue-tied, and I'm aware of that; sometimes I just start to feel like I'm gonna faint or pass out. And sometimes I can stop it there, but after that I don't really know what happens but I think I just fall on the floor or fall, if I was sitting in the chair I might flop back. And then I wake up.
And can you hear what's going on around you?
No, I can't remember anything about it
And are your eyes open or closed?
I think they are closed from what people have said.
And when you come round you've got a thumping headache?
Awful, awful headache and I usually feel sick and I'm frightened. Because I know what's happened.
Tests for diagnosing epilepsy
A number of tests can be carried out which may or may not support a diagnosis of epilepsy, although not everyone needs to have every test, and tests on their own cannot confirm or rule out a diagnosis of epilepsy.
These tests may help to find out if a cause for the seizures can be identified. Tests can include electroencephalograms (EEGs), blood tests, and neuroimaging or brain scans (MRI and CT scans).
A diagnosis of epilepsy is primarily made on clinical grounds. Tests, the medical history of a person, information about what happened before, during, and after the seizure(s), as well as videos of their seizures, if available, are very important for making a diagnosis.
Experiences with epilepsy diagnosis
Some of the people we interviewed recalled having a medical history taken and what was involved in the process.
Many people we spoke with discussed other tests that were done to reach a diagnosis.
Although some people noted that they did not remember tests very clearly, others described them in detail. One man explained that a brain tumour discovered during the tests was causing his seizures.
Recalls the medical history she had as part of her diagnosis.
Recalls the medical history she had as part of her diagnosis.
And its actually, thinking back on it, its not that bad a system because what the registrar did was take a really, really comprehensive medical history and they did all that leg work that the, you know that the overseeing doctor would have ordinarily had to spend his time doing. And you know she was, she was really good, she was really thorough. I just didn't realise how much I didn't know about.
What kind of questions did she ask?
She went through the history you know, 'When did it start?' 'How did you feel?' 'Did you have this kind of symptom, did you have that kind of symptom?' I've kept all my doctors' letters and things like that so I gave her all of those so she could read through the history and see what drugs I'd been taking and that sort of thing. But basically we took it step by step as we went through. I tried to remember dates and things like that as best I could but a lot of it you just, you don't remember. And it is significant when you change your medication and you probably should pay attention to when you did things and what you did, when you did them. So she actually just took a really thorough history and then she did the standard neurological tests' look at my finger here, look at my finger there, and scratch the bottom of your feet with a little sharp pointy thing (laughs). She did all of that and then left me to, she said 'Hang out here,' and she went and had ten minutes with the overseeing doctor, the overseeing specialist, and gave him the history that she'd just taken, which took her forty-five or so minutes with me. She gave that to him in ten minutes.
Explains that a tumour was causing his seizures and was discovered during the tests.
Explains that a tumour was causing his seizures and was discovered during the tests.
Well anyway I'll go through these, this treatment, but I also found out that the tumours were, where they were laying on my brain, it was causing me to have my fits, my seizures. And basically they wanted to get rid of the tumour to eventually cure me.
It's been some years now since I've been on the treatment and I still have my fits but I don't have as many as I used to.
EEGs and brain scan testing
People described what they remembered from having EEGs and brain scans.
While some people explained that the MRI scan was painless, a few people felt claustrophobic while having the test.
One woman recalled that testing went on for over 2 years and she described her feelings when she watched her seizures on video.
Several people noted that they would have liked more information about the diagnostic tests, why they were being done, and what they proved (see 'Finding Information on epilepsy').
Recalls her experience of having an EEG.
Recalls her experience of having an EEG.
Recalls that having an MRI was painless and all part of the process.
Recalls that having an MRI was painless and all part of the process.
Recalls the tests he had and feeling claustrophobic during the MRI scan.
Recalls the tests he had and feeling claustrophobic during the MRI scan.
Yes, I've undergone a CAT scan, an MRI scan, the EEG, the electroencephalograph, I think that's the way they say it, where they stick this thing like a crown on your head and you're wired into a machine.
Can you tell me what the CT scan involves?
Yes you lie on a, like a stretcher on this machine, its got a hoop and they just put your head inside the hoop, the rest of you is outside and its not at all unpleasant. You just see this little red light whizzing round and round in a circle and back again as they're taking the scan. And I have been on the other end of the scan, I've been, in the Red Cross we took a patient in to have a CT scan and I've seen how it forms in the control room there. Masses and masses of photographs that slice, effectively slice your head and its x-rays really, or a kind of x-ray.
And the MRI?
That's a different kettle of fish. I am not claustrophobic at all but I'm afraid I was in that machine, its very, very noisy, it rumbles and you're in a very, very confined space, I couldn't get out of it quick enough. But again I think it produces much the same sort of result as a CT scan, in other words it slices the body.
Waiting for a diagnosis
For many people, waiting for a diagnosis can be worrying.
One man discussed some of the difficulties with diagnosing epilepsy. Some people recalled what they went through before a diagnosis was made.
One man said that the various tests he had proved that his seizures were actually non-epileptic (see 'Non-epileptic attacks').
Discusses some of the difficulties with diagnosing epilepsy.
Discusses some of the difficulties with diagnosing epilepsy.
So really in the future, in the next five or ten years, there has got to be a push of not only more neurologists available but also help from people like nursing staff.
Explains that the tests he had showed that his seizures were non-epileptic.
Explains that the tests he had showed that his seizures were non-epileptic.
...It was really assuring that somebody was going through the right tests. So then he said "Look I don't know whether you have temporal lobe epilepsy or not but I'll tell you what I will do." He said "I will, I will er check your EEG again and I will check your telemetry again and I'll check your MRI again." He said "I want to look at these three things again, particularly the telemetry because," he said "there's something in the telemetry report that I'm not very happy with about certain peaks and troughs that I'm not very happy with and," he said "I want to look at that again and discuss it with somebody [hospital]. So he then said "I will refer you to a clinical psychologist at a very good hospital in London and," he said "I'll come back to you about whether I think you're temporal lobe epilepsy or not." So when I went the second time, after a proper interview and everything he said "I don't think that you are temporal lobe epilepsy."
'So he said "I don't think that you are temporal lobe epilepsy but it's on a balance of probabilities that I say this, as with many things." He said "I think that you're having seizures that are called non-epileptic seizures." And he said "I think you could benefit from going to see a clinical psychologist."
For more information see our resources page.
See also 'Impact of epilepsy diagnosis' and 'Signs and symptoms of epilepsy'.
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