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BRITISH BROADCASTING CORPORATION
RADIO SCIENCE UNIT
CASE NOTES
Programme 12. - Epilepsy
RADIO 4
TUESDAY 28/03/06 2100-2130
PRESENTER:
MARK PORTER
REPORTER: TRISHA MACNAIR
CONTRIBUTORS:
HENRY SMITHSON
HELEN CROSS
SALLY GOMERSALL
JIM MORROW
JOHN DUNCAN
JANE BIDDEPH
PRODUCER:
ERIKA WRIGHT
NOT CHECKED AS BROADCAST
LLOYD
It all started in 1986 when I had a car crash. Sadly I bumped my head. Shortly after that I started to get these dizzy faint spells, I would get slight blackouts. To be quite honest I do regret not seeing a doctor. And it all carried on until one night I was asleep and I just had a major seizure in my sleep. I could feel where I'd bitten into my tongue, rushed to the hospital. They said it could be epilepsy but they needed to be absolutely sure, for me to have another seizure then they would confirm it. About a week later, yes, I did have another attack. Now I'm a person, I have a lot of friends, I have a big family and as soon as people started to see me having seizures, because it was sometimes occurring in front of people, I noticed that big scale of friends started to sort of get smaller. And that's when you really know who your true friends and family are.
If I get far too hot it's very likely to bring on a seizure and then I'll come round within a few seconds. I take three tablets on a daily basis. Life did go on - it's not the end of the world. People just need to understand clearly what epilepsy is all about.
PORTER
And that's exactly what we intend to help you do over the next half hour.
Lloyd is one of nearly half a million people in the UK who have some form of epilepsy, but despite being that common, it remains stigmatised and poorly understood.
As well as discovering what actually happens to the brain during a seizure - and why - I'll be visiting Great Ormond Street to find out about the challenge of treating epilepsy in children.
We'll be hearing the latest thinking on epilepsy and pregnancy - what effect does medication have on a developing baby, and what effect does being pregnant have on the mother's epilepsy.
And I'll be talking to a woman whose epilepsy was cured by surgery to remove the part of the brain responsible for her seizures. While Tricia Macnair reports on an exciting new scanning technique designed to help the surgeon pinpoint the problem area, and minimise collateral damage to nearby structures that control vital functions like memory and speech.
My guest today is Dr Henry Smithson who is a GP, a senior lecturer at Hull York Medical School and Chair of the Epilepsies Guidelines Group at the National Institute of Health and Clinical Excellence - NICE.
Henry, the term epilepsy encompasses a wide range of different problems, with very different symptoms, what is the common factor that unifies them?
SMITHSON
Epilepsy really means that people's brains are a bit more sensitive than normal, that our brains are controlled by accelerators and brakes within the brain, they're chemicals. But people with epilepsy have an over-sensitive brain where the accelerators, the excitatory neurotransmitters, as we call them, are overactive and so they can cause an excess of electrical activity within the brain.
PORTER
And what are the most common forms of epilepsy, how did that chemical balance actually present?
SMITHSON
It depends on which bit of the brain's involved. The commonest form is when a part of the brain is involved to start with, the commonest bit of the brain affected is the temporal lobe, so people can feel as though they've got indigestion or abdominal bloating, they can become unaware, their memory can be affected, they can even smell things in a funny sort of way ...
PORTER
And remain fully conscious throughout?
SMITHSON
Some remain fully conscious, sometimes as the seizure passes to the other side of the brain they lose awareness and of course that's the other sort of epilepsy, which is the generalised epilepsy affecting both sides of the brain from the start of which the commonest one is what we call tonic clonic epilepsy, that's when people fall to the ground and they twitch and convulse.
PORTER
Which will be the image I think is familiar to most people with epilepsy and might have seen it themselves with sort of throes occurring the high street. But that only accounts for in fact a minority of cases.
SMITHSON
Yes only about 35 or 40% and of course not everybody who convulses has epilepsy.
PORTER
And who gets epilepsy and why?
SMITHSON
Some sorts of epilepsy run in the family. Some people get epilepsy, as Lloyd did, after an injury to the brain. But it's commonest in the very young and the very old.
PORTER
And do we actually know why?
SMITHSON
In the young, generally, there is some form of brain damage, brain abnormality, perhaps it's because of brain injury at birth, sometimes it's because of some sort of developmental problem as the baby's brain is growing in the mum's womb. In older people it's usually related to damage of the brain caused by hardening of the arteries.
PORTER
Furring up - something that happens to us all to some degree.
SMITHSON
Indeed so.
PORTER
How's it diagnosed?
SMITHSON
We diagnose epilepsy simply by listening to the story told by the person with the condition and anybody who's witnessed any of the episodes. It is simply based on the history, there is no gold standard investigation to confirm epilepsy. We can scan the brain and that can help define if there's any abnormality of the brain causing this and there's the brainwave test - the EEG - which can sometimes show us a pattern of irregular brain activity. But people with epilepsy often have normal brainwave tests and sometimes people without epilepsy can have some unusual brainwave traces on the EEG.
PORTER
And we often get it wrong.
SMITHSON
Somewhere between 15 and 25% of cases are misdiagnosed, yes.
PORTER
And the implications presumably - there are people there who have the stigma of being told that they have epilepsy, they're on medication they don't need and probably more to the point the actual underlying cause of their "seizures" - in inverted commas - is not being investigated.
SMITHSON
Absolutely. I think we've got to be very careful when we donate the label of epilepsy to anybody, we've got to be pretty sure of the diagnosis. And certainly, Mark, in my practice I would never diagnose it on my own and the guidelines from NICE do say that the diagnosis should be confirmed by a specialist with not only an interest in the condition but an expertise as well.
PORTER
Well as Henry mentioned, seizures can start at any age, including childhood. Helen Cross is Consultant Paediatric Neurologist at Great Ormond St Hospital in London.
CROSS
We estimate the prevalence of epilepsy to be 1 in 200 children in the UK, which means there's probably around 75,000 children and young people with epilepsy.
PORTER
And do you see a different presentation in children than we might expect in adulthood, are there some sort of typical stories?
CROSS
Two - relatively the commoner types of epilepsy that perhaps may present to the district general paediatrician are a form called Benign Rolandic Epilepsy, where children present perhaps between 5 and 10 years of age with seizures from sleep, maybe involving the face or one arm, they may or may not be conscious throughout that. And they may be relatively frequent or infrequent. And if relatively frequent then they respond very promptly to medication but we do know they grow out of it in teenage years.
Another type is where children present, similar type of age, with blank spells, they can be quite frequent, not necessarily interrupting with their learning and again they respond very promptly to medication and there's about a 70-80% chance they'll grow out of it.
PORTER
But presumably the spectrum of the sort of conditions that you see are just the same as we see in adults with epilepsy - they vary from the quite benign to potentially quite serious.
CROSS
Certainly we see a wide - different variety of epilepsies, that are relatively easy to treat and a high chance of growing out, to those where the seizures are very frequent, they don't respond very well to medication and there's a high association with learning behaviour difficulty.
PORTER
Are the treatment options that you have the same as somebody dealing with epilepsy in adulthood?
CROSS
The drugs we have available are the same as those we have in adults and in fact 75% of children that we put on medication will respond and/or go into spontaneous remission. Of course then in children where it's more difficult to control with medication we may be thinking of other options such as surgery where seizures are coming from one area of the brain and we may think about whether we can take that out without causing consequence to the child or indeed diet - ketogenic diet is one option, the high fat diet - which has been shown to be useful in children with difficult types of epilepsy.
PORTER
What effect can seizures and/or their treatments have on a child's development?
CROSS
Very much early onset epilepsy but sometimes epilepsy coming on later in childhood can be associated with increased learning difficulties, developmental issues and also behaviour difficulties. The exact mechanisms involved in that are uncertain, although it's likely frequent seizures, particularly in the first two years of life, are likely to interfere with the developmental process in the brain, the learning processes in the brain and we find that seizure control is the most optimal way of dealing with that, although we may not reverse it completely. Of course we have to think about medication but more often or not it is the frequent seizures that are causing the learning issues, rather than medication itself. It's all too easy to blame medication because it's an external source.
PORTER
What about restrictions on activity - what advice do you give to the parents of a child who's having seizures about what they can't do?
CROSS
The only thing that I say is forbidden really, which doesn't make me very popular with boys, is climbing trees, it's not going to be very safe if you have a seizure at the top of a tree. However, riding a bike can be possible, albeit with a helmet and not on a busy street, so thinking if you fall off it's not a consequence to oncoming traffic. Swimming is possible, if you have somebody keeping an eye on you on a one-to-one basis, whether it be the side of a pool where someone can jump in straightaway or perhaps a buddy system, when going into teenage life. The other thing that can offer major consternation in teenagers is having a bath - you can drown in very little water - so having a shower is by far safer. And there is always the ongoing issue of locking the bathroom door and that has to be negotiated as to what's safe and not safe.
PORTER
Helen Cross talking to me at Great Ormond Street.
You are listening to Case Notes, I'm Dr Mark Porter and I am discussing epilepsy with my guest Dr Henry Smithson.
Henry, what about febrile convulsions - around 1 in 30 children under 5 will have at least one seizure associated with a high temperature, does that predispose to epilepsy later in life?
SMITHSON
It depends really how many febrile convulsions the children have. Generally children who have one febrile convulsion which settles pretty quickly they may not be at an increased risk of epilepsy. But there are some children where perhaps the febrile convulsion may last for a longer time than we'd expect, who may be at risk and certainly if children have more than one convulsion they may be at risk as well.
PORTER
Right, let's move on to treatment. How do we decide when to start medication?
SMITHSON
The medication is only started after the diagnosis is confirmed and in the UK the diagnosis is often only confirmed when there is a second seizure. Epilepsy in this country is defined as recurrent seizures, so it's got to be more than one. Sometimes, however, in some patients who have their first seizure, if we find that they've got some area of damage to their brain and that would mean a brain scan or if we find that there's a characteristic and serious pattern to the brainwave test, then sometimes specialists would start medication after the first seizure.
PORTER
What are the medicines actually doing?
SMITHSON
Balancing those chemicals in the brain. They work in different ways but it's all to do with trying to reduce the electrical sensitisation within the brain.
PORTER
Reduce the excitability of the brain I suppose.
SMITHSON
Absolutely.
PORTER
And presumably that's going to have side effects because the brain does a lot of important things other than have seizures?
SMITHSON
All epilepsy medications can give some side effects. Sometimes people feel a bit sleepy, sometimes they feel a bit unsteady, sometimes they have trouble speaking clearly. Some medications have particular side effects - some have rashes, some unfortunately can even make people behave a bit differently. But generally if the dose is started at a low dose and slowly increased side effects are generally mild or not noticed.
PORTER
Well one area of common concern is the effects that anticonvulsant medication can have on a developing baby. Sally Gomersall found out she had temporal lobe epilepsy when she was 29 and neither received, nor sought, advice before she fell pregnant with her first child 14 years ago.
GOMERSALL
When I realised I was pregnant I went to my local general practitioner, asked him what the effects may be of my anti-epileptic drugs on the baby. But he was quite negative and he said the damage will already have been done by now. I really was just keeping my fingers crossed. The drug I was taking does in fact have quite a low risk - less than 3% - and I certainly felt that it was riskier to take it away and have seizures during the pregnancy rather than continuing to take it. And I was really, really well, in fact I had less seizures than I would have done normally.
PORTER
Dr Jim Morrow is consultant neurologist at the Royal Victoria Hospital in Belfast and the man behind the UK Epilepsy and Pregnancy Register. So what are the dangers facing pregnant women?
MORROW
I think we're still learning. And that's a terrible thing to say when many of the drugs that we are commonly using have been around for 20 or 30 years. It's generally recognised that a woman with epilepsy, on anti-epileptic drugs, has a two to three times increased risk of having a child with some form of abnormality or malformation.
PORTER
And does that vary from one class of drugs to another or is it a group effect across the board?
MORROW
Up until recently we didn't know, it was thought to be perhaps a group effect. But there are some epilepsy in pregnancy registers starting to report now, ours among them, in which we're seeing differences between the drugs, with some drugs having a slightly higher risk than other drugs. But I think our study, from Belfast, has added some reassurance to mothers, in that while yes we do think there is an increased risk we have to look at the size of that risk. And what we have generally found is that it's about 4-5% overall risk of a child with a malformation if you're a woman with epilepsy on an anti-epileptic drug, compared to about a 2% risk in the population in general. But if you turn that round - if you're a woman with epilepsy taking drugs you've still got a 95-96% chance of having a perfectly normal child.
PORTER
So what should a woman do if she's taking anticonvulsant medication for her epilepsy and she's planning on getting pregnant, presumably the key word there is planning - to seek help and advice early?
MORROW
Absolutely, I mean I think what we would advocate is pre-conceptual counselling. If you're going to make changes you want to make changes to the drugs before you become pregnant because if the drugs are going to in any way affect the foetus then they will do so in the very early weeks, almost before you know you're pregnant. So this is a really good time to look at your epilepsy and look at the drugs.
PORTER
Are there any other steps that a woman can take to minimise the risk to her child, other than ensuring that she's on appropriate medication in the lowest possible dose?
MORROW
We would generally recommend taking folic acid, and taking folic acid at the higher dose - i.e. 5 milligrams. Again when you're thinking about becoming pregnant.
PORTER
So that's more than 10 times the standard dose that a normal woman would take?
MORROW
Yes, basically because one of the risks that we realised is for neural tube defects - spina bifida - and folic acid has been shown in the general population to reduce the risk of spina bifida if taken preconceptually.
PORTER
Let's look at it from the other angle then. How does being pregnant affect the woman's epilepsy?
MORROW
Overall it's a rule of thirds probably in that about a third of women with epilepsy will remain exactly the same, in a third it may actually improve but in a third it may get worse. There is an increased risk of maternal death in women with epilepsy. Now it's impossible to delineate why there is this increased risk but one of the big worries is that it may be because of increased seizure frequency, it is recognised that seizures themselves can be very dangerous and people can die in seizures. Happily it is very rare. But one of the things that may provoke it is abrupt stopping of the anti-epileptic drugs.
PORTER
And what about the effects on baby?
MORROW
We really don't know. Babies are pretty well protected in the womb and we haven't found any increased risk of major malformations associated with seizures but some studies have suggested that there may be and again increased seizures during pregnancy may result in some developmental delay of the babies but again this is still in the very early stages and it's really not proven as yet.
PORTER
When baby is born does he or she then have withdrawal effects from the medication that the mother's been on for the nine months?
MORROW
You do occasionally hear of babies being a bit jittery after birth and sometimes that may be down to some withdrawal from the drug. But the level that baby's exposed to is usually quite small and it's an unusual occurrence.
GOMERSALL
Things have really improved for women with epilepsy in the last 10 years. But what I want to say is it's really important that you don't just stop taking your anti-epileptic drugs because that is actually a risk of sudden unexpected death due to epilepsy. So it's really crucial that women plan their pregnancy, get counselling beforehand, make their decision, certainly don't ever just stop taking their medicine.
PORTER
Sally Gomersall.
Henry, we heard Jim there talking about conception planning but what about contraception planning?
SMITHSON
The important things are to make sure that if people with epilepsy are on medication that those medications don't reduce the efficiency of either the pill or the contraceptive injection.
PORTER
Which some can?
SMITHSON
Some can and if your doctor tells you that you're on a medication that can reduce the effectiveness of the pill then it's best to take two of the contraceptive pills rather than one each day or to have the contraceptive injection every 10 weeks instead of every 12 weeks.
PORTER
And that's not universally known though is it, either amongst women themselves or dare I say GPs?
SMITHSON
No I don't think it is. If people are on things like Carbamazepine or Phenytoin, for instance, two commonly used drugs, they should discuss this with their doctor if it's something that's been passed over.
PORTER
What about other options for treatment? What do you do with somebody who you're having difficulty controlling their seizures with all the available medicines that we've got now?
SMITHSON
The first thing that we do, I feel very strongly, is to have a conversation with that person and see how they feel about the medications, to see if indeed they are taking them the way that we expect them to take because we know that probably half the people on medication, on medical advice, are not following the advice that we would expect. But assuming they're taking the medicines and they still are having troublesome seizures then we should refer them back to the specialist who could then scan the brain or check if the brain has been scanned to see if there's a particular area of the brain that's causing the epilepsy because there are some parts of the brain that all things being equal can be removed by neurosurgery to try and cure the epilepsy.
PORTER
But presumably identifying that focus, we've already said that a lot of these people don't have any demonstrable abnormality on scans, so it's presumably only going to apply to a minority of people?
SMITHSON
Epilepsy surgery is only used for a very small number of patients, perhaps only 1 or 2% of people with epilepsy are even considered for surgery and not all of them are found to benefit from it. So it isn't something that is very often used but occasionally can be very effective.
PORTER
Well Sally Gomersall was offered surgery for her temporal lobe epilepsy and it was a success, but there were side effects.
GOMERSALL
My children were both under five when I had my operation in 1996, so coming up for 10 years now, which literally took away the focus of my seizures, so where all my seizures originated from. And I've been seizure free since and of course that's absolutely changed my life from being quite dependent on my family to look after my children and hugely independent and able to drive a car. But my right temporal lobe operated my facial awareness, which really is your visual sensor. Visualising anything really in my memory - recognising people's faces, retracing my route in a building. In my work environment when I'm doing training courses I make everybody wear a sticky label on their chest so that if they walk out the room and come back in I know they were here earlier, so I can manage on a day-to-day basis without that part of my brain.
PORTER
Although the temporal lobe is a common focus for seizures identifying the part of the brain responsible is often difficult, and sometimes impossible. And as well as targeting the right spot, it's vital that surgeons do as little damage as possible to surrounding structures, particularly as it's not always clear what effects such damage will have. As Tricia Macnair discovered when she visited The National Society for Epilepsy to see a new type of brain scanner that could help target surgery more effectively.
ACTUALITY
Okay Malcolm, so you're okay in there? We're just ready to begin the first scan now. You're going to hear the scanner start tuning, just for a few seconds, and then we'll go straight into the scan. So we're just going to start tuning now.
MACNAIR
Well I've come along to the National Society for Epilepsy at Chalfont St Peter and joining me here to tell me a little bit about the work is the medical director Professor John Duncan. And we're in the MRI unit where a patient is going through the MRI scanner undergoing one of the studies. John, tell me a little bit about the work of the centre here.
DUNCAN
Well the society as a whole provides care for many people with epilepsy, the emphasis of where we are at the moment, in the MRI unit, is to use the latest MRI brain scanning technology, Functional MRI or FMRI for short to understand the causes of epilepsy and also the consequences. And in addition to apply this as soon as we can to clinical practice. Now these techniques are a way of identifying in the brain where different functions are carried on, so normal functions like language and memory and also where abnormal activities are occurring, such as epileptic discharges.
ACTUALITY
Okay, so the table is just going to move now and it's just a short sequence, just to find out exactly where you are in the scan.
BIDDEPH
I'm Jane Biddeph I'm a senior radiographer at the MRI Unit and I'm just taking part in an FMRI study with a patient and we're undertaking language and memory skills. We'll be doing three six minute scans, followed by a long 15 minute scan. And in a moment they're going to see words and letters on the screen and they just have to react and repeat either the word or think of verbs beginning with that letter.
MACNAIR
John, explain why they're doing this, why are thinking of words, what are you looking for with the scan?
DUNCAN
We're particularly interested to know which side of the brain people use to speak with, which side they use for language. In general people who are right handed in particular use the left hand side of the brain for language. Once the results are processed what we get is an image of the blood flow to different parts of the brain. The principle here is that a part of the brain that is active and doing some tasks has an increase in blood flow, whereas parts that are not active have a decrease in blood flow. So by comparing the scans done when the person is thinking of words against the times when they're not thinking of words and subtracting one from the other, in effect, you identify the area of the brain that is involved and has an increase in blood flow in carrying out that task.
MACNAIR
Well what is the point of all this, what's it going to do to help you treat people with epilepsy?
DUNCAN
Well for individual patients it's important for planning surgical treatment because if we're going to plan the surgical removal of the part of the brain that is causing the epilepsy it's very important not to cause the person some new problem, such as, for example, taking away their ability to speak would be a disaster.
ACTUALITY
Okay, so nice and still now, just for one and a half minutes. [BEEPING]
MACNAIR
John, tell me about the work you're doing with memory too, you're looking at how that's affected in epilepsy.
DUNCAN
Again using the functional MRI technique people can be in the scanner and they can be asked to remember words, pictures and faces. Now these important memory functions are carried on in different parts of the brain, so this is very important again in understanding the effects that epilepsy has on memory, particularly for people with epilepsy arising at the temporal lobes, difficulties with memory is one of the biggest things they complain of, in addition, of course, to the occurrence of seizures. So we're hoping to understand how epilepsy affects memory functions and again for individual people when surgery is in contention we hope to be able to map where their different memory functions are occurring so we can firstly advise them what particular risks they run to their memory, should they have surgery. And we hope leading on from that to be able to plan surgery to minimise the risk of affecting those functions.
PORTER
John Duncan talking to Tricia Macnair.
Henry, what's the long term outlook for people with epilepsy?
SMITHSON
Sixty or seventy percent of people with epilepsy can expect seizure control with medication. So generally it's pretty good. And indeed some people if they're free of seizures for a period of time can even discuss with their specialist to see whether they still need the medication. In children we suggest that if they've been seizure free for two years they should perhaps discuss whether they need medication but in adults we usually suggest five years before they may want to discuss this. But of course some people are content to continue medication to try and maintain seizure freedom, so they don't lose their driving licence, they're not affected by the epilepsy.
PORTER
Talking about driving licences, what happens if you are seizure free on medication, can you drive on medication?
SMITHSON
It depends on the country. In the UK, if you're seizure free for a year on or off medication, then you can reapply for your driving licence. That's the ordinary driving licence for a car. If you're driving a bus or a goods vehicle then you've got to be seizure free for 10 years.
PORTER
What should someone do if they're with someone who has a seizure?
SMITHSON
Keep them safe. Don't stick anything in their mouths. Make sure that they can breathe and let the seizure go away on its own. If the seizure lasts for more than 5 or 10 minutes then perhaps call an ambulance, although really a lot of people who have seizures get better on their own, as long as they're kept comfortable and dignified and really don't need to be whisked into hospital every time they have a seizure.
PORTER
And if someone's known to have a form of epilepsy and the seizure doesn't last more than 5 or 10 minutes, they get fed up - I mean some of my patients come to me and say they get fed up with waking up in ambulances or in A&E departments by well meaning people.
SMITHSON
Yes it's something that I guess in the television age everybody sees a blue light and says gosh we've got to take people to hospital. But if you leave them somewhere safe, so they can sleep off the seizure, then they generally wake up fit and well and a little bit sort of muddied or bloodied but otherwise able to go home and carry on.
PORTER
Dr Henry Smithson we have to leave it there, thank you very much.
This is the last programme in this series, but we'll be back at the beginning of May for another run. Until then, goodbye.
Ends
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