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BRITISH BROADCASTING CORPORATION
RADIO SCIENCE UNIT
CASE NOTES 5. - Light
RADIO 4
TUESDAY 11/01/05 2100-2130
PRESENTER:
MARK PORTER
REPORTER: CAROLINE SWINBURNE
CONTRIBUTORS:
TONY CHU
HUGH BARR
ANN FARMER
GORDON DOUGAL
PRODUCER:
GERALDINE FITZGERALD
NOT CHECKED AS BROADCAST
PORTER
Hello. Today's programme explores the healing properties of light.
I'll be discovering how lasers are being used by surgeons to prevent cancer of the oesophagus and by skin specialists as an alternative to long term antibiotics in the treatment of acne.
CLIP
Patients really are quite ecstatic about it, we've got patients who have tried literally everything and they've still got acne. A number of patients after the first treatment improves, after the second treatment we've virtually got them clear and then we continue on treatment to keep them under control. And so yeah they're incredibly happy.
PORTER
And I'll be finding out how a simple device that emits infrared rays could take up to 10 years off your appearance.
CLIP
Well initially I noticed that I was getting bags under the eyes and my sort of face was saggy and I thought I wonder if this technology will work.
PORTER
One in five of the British population has heartburn due to reflux - backflow of their stomach contents into the lower part of their oesophagus or gullet. While the stomach is well protected against its acidic contents, the oesophagus is not, and repeated reflux can result in burning of the gullet lining causing precancerous change - a condition known as Barrett's dysplasia.
One in ten patients with reflux will develop Barrett's dysplasia, and 10% of them will go on to develop oesophageal cancer - typically 10-20 years later.
Cranfield University's Professor Hugh Barr, a consultant surgeon specialising in oesophageal disorders, has been at the forefront of work to prevent oesophageal cancers by identifying those most at risk and treating their precancerous changes using a laser. I caught up with him during one of his busy operating sessions at Gloucester Royal Hospital.
ACTUALITY
BARR
It usually occurs in people who've had long term reflux disease, acid reflux, and they're diagnosed as a condition called Barrett's Oesophagus, that is a change of the lining to protect against reflux but it sets up cycles that can lead to cancer.
PORTER
So - because stomach acid, I mean it's about as strong as battery acid isn't it, I mean the stomach is protected of course against its own juices but the lower part of the gullet isn't, so when this acid's coming back up it's damaging the gullet and that's the precancerous change.
BARR
That is the precancerous change. And it's diagnosed at a telescopic test - we pass a little telescope down your mouth with you awake or with very light sedation and have a look at the area and if there are any areas that look suspect we take a little biopsy and look at those and then if those biopsies show that it may degenerate to cancer we treat it here.
PORTER
So up until you were offering this sort of treatment what would have been the option for someone who had these precancerous changes? Would surgery be the only option?
BARR
Usually if they have what we call high grade displays of very advanced precancerous changes then they would have to have their oesophagus out, which is a very major procedure. Otherwise if it was less so and they weren't fit for surgery then they'd just be watched and intervention would occur at cancer. So it was not a very satisfactory solution, in fact it was very difficult for the patient because they either had to wait for the cancer to develop and then have radical surgery or have radical surgery to preempt cancer developing, which may not of course develop in their lifetime, something else may happen to them.
PORTER
So what are you actually doing with the laser?
BARR
What we do is we pass the telescope under a little light sedation and then we burn off the surface where these changes are because the changes lie in the first millimetre of the oesophagus and we just burn it off with the laser or we use photodynamic therapy, that is we give them a drug that localises to the surface and then put down a laser fibre to activate the drug in the lining of the oesophagus, the lining separates a few days later and then they resurface when we put them on some powerful drugs to heal up the oesophagus and it prevents the cancer developing. The chemical activation's very similar to what happens in nature with photosynthesis - these are natural reactions that occur in nature being exploited in the body.
PORTER
The sort of reaction that might be familiar to some gardeners because there are some types of plants, aren't there, that you can pick up when you actually get weeds on the skin and you get a rash that develops over the next three or four days - that's photo sensitisation.
BARR
Absolutely.
Mr Lawton is one of our special patients who has come from Devon. He's a very fit gentleman who has been noticed to have precancerous changes in the lining of his gullet. It was discussed with him the options of losing his gullet and also of just watching it develop. But we now have the middle way where we can destroy the lining and he came a few weeks ago, had the injection of the sensitiser and we've activated the drug in the gullet about six to seven weeks ago and we're just now, this morning, going to look down and see what effect we've had on the area of his oesophagus.
PORTER
How soon before the treatment do you need to give these chemicals?
BARR
Two days.
PORTER
Two days.
BARR
Forty eight hours before and they're kept in a darkened room here. It's really quite restrictive because as you see Mr Lawton's a very fit, healthy man he wanted to be out and he had things to do.
PORTER
You had the treatment what seven weeks ago?
LAWTON
Yes, 15th of November.
PORTER
And what did it feel like afterwards when you got home?
LAWTON
I didn't feel any different to begin with but gradually my face became very swollen and my skin started to peel off round my chin particularly and my lip and one ear and that one ear it took a long time for that to reappear. But I think that was because I couldn't avoid being in the light - I wore a wide brimmed hat and glasses and gloves ...
PORTER
What even in Devon at Christmas time?
LAWTON
Even in Devon at Christmas time, yes.
BARR
We did have a bright - it was a bright Christmas. I did notice you were a little bit reddened today.
LAWTON
Right, right.
BARR
Did you have any pain in the gullet?
LAWTON
Not at all.
BARR
None at all excellent.
PORTER
So it was only just - that those are the skin side effects from the sensitising chemical.
BARR
...exactly, he describes them very well that he's had skin photosensitivity and the bright sunlight of our South coast was a little too much for him and he's a very fair skinned man.
PORTER
And how soon after the procedure's done will the photosensitivity wear off?
BARR
We do like gradual exposure to light because it does use up the photo sensitisers in the skin, usually about a month to two months, he can start taking less precautions now, we don't have any dark glasses for him, we've not taken any specific precautions today and his photosensitivity won't trouble him anymore.
Okay Mr Lawton I want you just to rest nicely there and just follow this down. We're just going over the back of his throat. And we're just going to drop down into his gullet.
Close. But this is a very, very good result Mr Lawton. It's been well worthwhile.
PORTER
You're happy with that to look at, so you're taking the biopsies now, what's making you choose the areas that you're ...
BARR
This is entirely random. This is why we're developing the laser technique to touch the tissue, so that we can actually look at it and say this looks unhealthy optically but you're quite right you can't tell. Open.
PORTER
It all looks perfectly normal to me.
BARR
It all looks perfectly normal, you're quite right, it all looks perfectly normal but we need to tell - close - at the time of endoscopy, so if we had a slightly false colour image saying look worrying area here, worrying area there and these are the techniques we're developing because taking the specimen, going to the lab, it's all a long time.
We've just finished now and as you see Mr Lawton's fine, we're coming out now and this looks absolutely a perfect result. He will need just a little bit more therapy at the bottom, just to be absolutely certain but I have to say brilliant. Okay, we'll just take out the mouth guard now, are you alright sir?
LAWTON
Fine thank you.
BARR
Well done.
PORTER
Did you feel any of that Mr Lawton - the biopsies or anything being done?
LAWTON
Yes.
PORTER
It's not very nice having to swallow the endoscope but it's not the end of the world is it really.
LAWTON
No.
PORTER
Very quick.
LAWTON
Getting used to it now.
BARR
The sequence to getting cancer from reflux usually start refluxing 30-40, you get your Barrett's metaplasia and that seems to protect you somewhat from the pain, maybe 50 and the cancer develops about 60-70. So it's quite a long time sequence, so we've got a very long opportunity to intervene and prevent it occurring.
PORTER
I'm just thinking with my GP hat on here, I've got an awful lot of patients who've got fairly classic heartburn which you can diagnose on the history, it sounds like they're getting this reflux, presumably the only way we're going to know if they've got precancerous changes is if they all have endoscopies and all have biopsies.
BARR
This is an issue that is exercising our professional societies and the NHS a lot. Should we endoscope everybody with reflux? Now I take a fairly strong position on that, that is controversial, I would. I think if you're in a risk group and you've got persistent reflux after a certain age you should have an endoscopy to identify whether you have the Barrett's change.
PORTER
We've talked about you using this treatment to deal with people who've got Barrett's oesophagus, precancerous changes, to prevent them going on to develop disease proper. What about people who've got cancer of the oesophagus?
BARR
Well only 20% of the patients who get cancer of the oesophagus come to surgery and radical therapy. We can give them chemotherapy, radiotherapy and surgical excision and that does work for some patients.
PORTER
What's happening to the other 80%?
BARR
The other 80% are just too unfit to withstand it and they often have to have palliative treatment - palliative radiotherapy - and they often don't survive the disease, that is why it's crucial we get the precancerous changes and prevent them getting it. We do use photodynamic therapy and laser therapy to palliate because the big problem when you've got a cancerous oesophagus is it blocks your oesophagus and you just can't eat.
PORTER
Can you use the laser to debulk those tumours, to give these people, even if they can't be cured, to give them a better quality of life?
BARR
That is also very effective - we can core out a new hole through and use photodynamic therapy to destroy the cancerous tissue so at least they can swallow and socialise because eating's so important and their quality of life does in fact improve. And that is a very effective means of what we call palliation - relieving the symptoms so we can look after them in other ways.
PORTER
Professor Hugh Barr speaking to me at Gloucester Royal Hospital - one of only six NHS centres currently offering laser treatment for Barrett's dysplasia.
I'm Dr Mark Porter and you're listening to a Case Notes special on the healing power of light.
Most people who have acne will have noticed that their skin improves after a spell in the sunshine, and light has been used to treat unsightly spots for years - with differing degrees of success.
The first attempts used ultra-violet light - in particular UV-B, the portion of sunlight responsible for sunburn - and herein lay a fundamental flaw - to get a half decent response patients had to undergo intense courses of treatment that left them sore and peeling, and at higher risk of skin cancer later in life. To cap it all, response rates were poor.
Then, 20 years ago, prompted by an ever increasing demand from his patients for alternative treatments that didn't involve long term antibiotics, Dr Tony Chu, a consultant dermatologist at the Hammersmith, started experimenting with blue light.
The bacteria responsible for acne are killed by blue light - add in red light which promotes healing - and you have the perfect do-it-yourself treatment that can be used at home to control acne without the need for antibiotic creams or tablets.
But Tony Chu felt he could go one better.
CHU
The story behind the laser is a curious one. I was approached by a company that had a laser and a number of their operators had reported that when they were treating acne scarring that acne seemed to improve. Now at that stage I had nothing to do with lasers, I was a complete sceptic, and when they came almost laughed at them I said - Well there's absolutely no way it's going to work but I like new toys and so give me a laser and I will try it. Within two weeks of trying the laser I was completely converted and we then put together a clinical trial, looking at 40 patients, which was a controlled trial. These patients were either treated or they were sham treated. So because of wearing blackout goggles they weren't sure what was happening but we treated the skin without the laser being put on. And we demonstrated really quite remarkable improvement in acne.
Now the extraordinary thing with the N-light is that with one treatment you can get a sustained improvement for up to three months. So you can have one treatment with the N-light laser, which would take 10 minutes to treat a face, and you can then be clearing and improving over the next three months without any other treatment. But that's quite remarkable.
ACTUALITY
PORTER
The treatment involves drawing a probe across the area to be treated, typically the face or back, in seven millimetre wide strips, a bit like mowing the lawn. Dr E Katarina Harakida is one of the dermatologists on Dr Chu's team.
HARAKIDA
It's not invasive, so it doesn't cause any bruising to the face at the level that we are using it. You use the probe and there is a light, so we cover an area of 7 millimetres during the treatment. And what we try to do is to cover the whole area that we treat, the whole face or the whole back, by putting each probe next to the other, so we cover the whole area with the laser treatment, it's just going through the whole area very, very slowly.
PATIENT
It is certainly, broadly speaking, painless, it just feels like a very hot pen being run all over your skin really. So it's momentarily uncomfortable just when the heat's on your skin but only for a very brief second, I certainly wouldn't describe it as painful, it's just like something hot being pressed on your skin for a moment.
CHU
When we first started using the laser we thought that part of the way it worked would be to kill the bacteria. The fact that it lasted so long showed that it was obviously not the way because if you kill the bacteria they'd repopulate very quickly and therefore you'd have to give treatments at least several times during the week. So that got my scientific brain working and trying to fathom out exactly how it does work. And we've now identified the mechanism that we think it does work. Now when you treat the skin with the N-light laser the laser energy is taken up by red, and it's the red of the red blood cells within the blood vessels. That warms the blood and that causes a sub-lethal, i.e. it doesn't damage the cells but damage to the cell's lining in the blood vessels. Now when that happens chemicals are produced and one specific chemical we've identified is a chemical called transforming growth factor beta. TGF-beta is a fascinating chemical. One action is that it will reduce inflammatory chemicals within any part of the body and that is almost certainly how it works in reducing the inflamed spots in acne, really quite dramatically. The most interesting thing I think is that it will stimulate a particularly form of white blood cell called a regulatory T-cell that could eventually turn off the whole inflammatory mechanism that is causing the acne to occur. And so it could eventuate in a cure.
PORTER
Which explains why many patients don't seem to need any further treatment after they have had four or five sessions under the laser.
PATIENT
I've been coming once every three months, it's definitely been beneficial, my skin's vastly improved as a result of it and I think that particularly contrasts with antibiotics - I've been on antibiotics for a couple of years without noticing much improvement. So it's nice not to be putting antibiotics down your neck but just turning up for this and I'd say my skin's probably 70-80% improved at the moment and I'm still sort of halfway through the course.
PORTER
This type of laser treatment for acne is not currently generally available on the NHS and is expensive at some 拢4-500 for a typical course.
Light sources don't have to be as complicated, or as powerful, as lasers to produce therapeutic benefit - a fluorescent tube is all that's required to help many of the five million or so people thought to suffer from some degree of seasonal affective disorder - SAD - at this time of year. And there's much more to SAD than simple "winter blues", as Professor Ann Farmer from the Maudsley Hospital in London explains:
FARMER
Seasonal affective disorder or SAD is a depressive illness that occurs most winters, not necessarily every winter. It generally starts in September or October, classically when the clocks go back, and remits in the spring time. The features are fairly typical of depression, in other words there's low mood, lack of energy, wanting to stay away from other people, poor concentration, that sort of thing. On the other hand it's also associated with considerable sleepiness and generally an increased appetite, so people typically want to sleep a lot and eat a lot of high carbohydrate foods. I think many people feel slowed up and sleepy during the winter months, especially after Christmas and New Year bank holidays, it's hard to get going again in January. But for many people who have seasonal affective disorder this is a real significant clinical problem, which really does interfere with their lives and their functioning quite substantially during the winter months.
PORTER
Who's most at risk?
FARMER
The people who get it are very much the people who get depression anyway. So there is an excess of women, we find for depression in general there are about two women to every one man who will get the disorder. People who have a family history of this kind of problem during the winter months are also more likely to suffer from it as well.
PORTER
Professor Ann Farmer. If SAD is due to falling light levels, then it's only fair to assume that artificially boosting ambient light may help. We sent Caroline Swinburne to Cambridge to investigate.
ACTUALITY
Well we have several different light boxes that may suit your needs ...
HAYES
My name is Steve Hayes, I'm the managing director of Outside In in Cambridge and we specialise in the lights that people use for treating seasonal affective disorder and other things to do with the body clock, like shift work and jet lag and some sleep problems. And they are light boxes in various shapes and sizes, typically it's something the size of small suitcase with a window on one side and when you turn it on there's gallons of light coming out of it. The one I've got in my hands here, quite small, this one's quite popular - I'm turning it on now.
SWINBURNE
It is quite bright isn't it.
HAYES
Well we're in a darkish room and that's what makes it look quite bright.
JACKSON
My name's Anne Jackson and for the last four years I've been using a light box. I live just outside Aberdeen in the North East of Scotland. Aberdeen is pretty dark in winter and sometimes in summer it's not much better. When I was on holiday people said to me, when I was on holiday abroad, people said to me I was just a different person in the sun and I was. It was like I'd been completely recharged and I could be myself - fully myself. But in Britain and specifically in the North East of Scotland, especially since the birth of my son 15 years ago, I have found it very, very difficult to counter any feelings of depression.
HAYES
Lots of light improves serotonin levels - that's true of everybody, whether or not they suffer from seasonal affective disorder. The likely explanation is that if you're vulnerable the levels are affected too profoundly and you just - you've not got enough to function properly in the wintertime when it's dull, so you're not getting that bright light that you need.
JACKSON
One day about four years ago I read an article in our local paper here written by a SAD sufferer and after I read it or during the time I was reading it I was thinking oh my god this is me, it's me, this is me, I can tick every box, why didn't I realise this? And the article recommended a light box.
HAYES
We're coming through now to the warehouse manufacturing area. This is where we assemble the light boxes and as we get closer I think you can see that - well you recognise the source of light bulbs we've got inside them, they're fluorescent lights of a reasonably standard sort, they're correct for the job, but they're producing light which is really not a great deal different to the light that you're getting out of the fluorescent light you've got in your kitchen, the point being that they're arranged so that you can get nice and close to them and of course that means that the light you're receiving from them is up, if you have a light meter then the needle's at the high end of the scale. And they're arranged to be visually comfortable for you without being too dazzling.
JACKSON
The light box is about 18 inches tall and about 6 inches - 6-8 inches - wide maybe. I can lie on its side and have it on top of my computer and it is an incredibly bright light. You don't have to look directly at it all the time, I just have mine on as soon as I go to my office in the morning it's on until I feel sufficiently recharged.
HAYES
Over on the other side there you can see we've got these - they're rather like a little bedside light with an alarm clock built in. And the other technique that's used is what's called dawn simulation and typically let's say you wake up at 7 in the morning the light would be set up so that it would just creep on at half past six, very slowly getting brighter over the next half hour, in other words it's copying the sunrise. It's a nice way to wake up and it's a civilised way to wake up, but beyond that there is a substantial body of formal peer review journal research which shows that it's an extremely effective intervention for seasonal affective disorder.
JACKSON
I cannot be without my light box now. The difference is like being barely together, barely alive, to being fully alive, alert, motivated and it's like somebody has plugged me in to recharge me. I would not ever want to be without my light box. It literally is the light of my life.
PORTER
Ann Jackson talking to Caroline Swinburne. Light boxes cost around 拢100 each but light therapy on its own won't be enough for everyone with SAD - some sufferers, typically those with more severe symptoms, may require antidepressants too.
So far we've dealt with the healing properties of visible light, but light doesn't have to be visible to exert a therapeutic effect. Two doctors from the North East of England - a GP and an eye surgeon - were researching the effects of infrared light on cold sores when they noticed an interesting side effect. A discovery that led to the development of a device they claim can reduce bags and wrinkles and take up to 10 years off your appearance. Too good to be true? We invited Dr Gordon Dougal to our Newcastle studio to find out.
DOUGAL
Well initially we were looking at the effect of infrared light on the treatment of cold sores. Now we did a clinical trial which demonstrated efficacy in the treatment compared to acyclovir.
PORTER
So that's that leading antiviral, so the light was actually killing the virus.
DOUGAL
No it wasn't. What we found is that it was actually having an effect on natural host cells, was making the immune system more responsive to fight the virus, rather than it actually killing the virus itself. So then what we did was we set a research student and we looked a cell cultures and we looked at how we could assault the cells to demonstrate a protective effect of the light. Now one of the assaults we chose was UV light and we found that the infrared light protected against the UV assault. So from that point on we thought well that's very interesting, in view of the fact that UV is a known photo ager we wondered whether it would have an effect on the ageing process. So we actually recruited 40 volunteers into our before and after clinical trial - it wasn't blind or anything else like that, it was a purely - get some decent photographs before and some decent photographs after. And we were surprised at how positive the effect was, I mean bags under the eyes had been reduced markedly.
PORTER
And what's actually happening?
DOUGAL
The effect takes about two weeks and just as any other tissue, connective tissue, in the body's turned over as a matter of normal physiology it looks like we're improving the quality - the elastin - produced by the cells.
PORTER
So this is one of the structural proteins in the skin - that pulls our skin up basically.
DOUGAL
That's right, we're not increasing the quantity of collagen, we're not increasing the quantity of anything, what we're actually doing is improving the quality of the elastin. So therefore the effect is - almost reverses the ageing process.
PORTER
Describe what the device looks like.
DOUGAL
It's about the size of a sort of - about one and half times the size of a mobile phone. It's sort of eye shaped and you place it over the area to be treated, usually around the eyes or sort of around the mouth or wherever you want really. And you apply it to the area where you want to treat the wrinkles for three minutes and then you move along about a centimetre, treat another three minutes and as - depending on the area you want to treat you just move it along by a centimetre each time and give the area a treatment for three minutes. It's very low power light, because obviously between the eye area you can't use high powers. But even with this low power the effect is quite marked.
PORTER
You say you had the - the volunteers have been using it at the moment and the response from that was pretty good, are you planning on taking this on to a proper clinical trial where people will perhaps be using dummy machines, like a proper blinded trial?
DOUGAL
Absolutely yes. We've got that in the pipeline to put before an ethics committee, proper double blind placebo controlled trial.
PORTER
So assuming somebody just wanted to treat fine wrinkles and bags around the eye how long would they have to use it for and how often?
DOUGAL
Ideally they'd use it at least once a day, if they really wanted a rapid response they'd use it twice a day. You need about 9 or 10 minutes per eye, so you'd need about 20 minutes a day at least, possibly 20 minutes in the morning, 20 minutes in the evening. And if you were to only treat one side of the face or one eye you'd notice a difference in about two weeks, if you compared the sides before and after.
PORTER
How long have you followed volunteers for - I mean is there a maximal time after which there's no more benefit?
DOUGAL
Oh I'm sure there must be, I mean we're talking about the ageing process - we're getting older everyday. You'd probably plateau off about four months.
PORTER
And then is there a maintenance - what happens if you stop treatment, do you go back to where you were before?
DOUGAL
It takes about a month for the effect to - not wear off completely but to begin to wear off, where you see the lines and everything are beginning to come back. A maintenance treatment would be about three times a week.
PORTER
And what about safety - people have their eyes closed when they're using these devices?
DOUGAL
They have to have their - well they don't have to have their eyes closed but in order - because the light obviously you're saying to people put the device by your eyes, because of that fact we're using very, very low power light, if you were to compare the light emissions of the product compared to a 60 watt globe ...
PORTER
A standard bulb.
DOUGAL
Yeah, the standard bulb, at one metre there's more light coming out of a 60 watt globe at one metre than there is coming out of this device. So as regards safety it's safe.
PORTER
So Gordon how long have you been using it?
DOUGAL
Initially I noticed that I was getting bags under the eyes and my face was saggy - you know these things happen as you get older - and I thought I wonder if this technology will work and I tried it on myself about five years ago. So I've been using it about five years, so certainly I've not noticed any long term effects - negative long term effects.
PORTER
And how much does it cost?
DOUGAL
A hundred and ten pounds, plus ten pounds postage and packaging.
PORTER
Dr Gordon Dougal talking to me from our studio in Newcastle. And if you want more information on that device or any of the other items mentioned in today's programme you can call the Radio 4 Action Line, that's 0800 044 044 or visit our website at bbc.co.uk/radio4.
Next week I'm off to prison. Join me for a medical perspective on life behind bars.
ENDS
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