Laser Surgery - The Fantasy and the Facts
Refractive Surgery (RS) - surgical techniques of modifying the cornea to correct refractive errors - is at present fashionable and widely discussed. Many Vision Educators find themselves challenged by sufferers from short sight especially on the lines of Why should I go to the trouble of trying to help myself when this operation will do it all for me?
Possible questions to discuss, therefore, would include all the aspects of cost effectiveness and risk assessment i.e.: What are the risks and level of risk involved as between VE and RS? What is the true relation between cash cost, personal time and trouble, and a given end result? What is the likely end result in each case? This article considers these questions, not so much from the Vision Educator's viewpoint, but mainly through the information and research made available by the people who practice and have experienced it, with just a few liberties taken in rendering jargon and medibabble into plain English.
Radial Keratotomy (RK)
One of the major developments in the medical treatment of poor sight over the last twenty years has been surgical modification of the cornea - radial keratotomy. Originally developed in the USSR, this has been hailed as a miracle operation, enabling the normalisation of sight in a few minutes of surgery.
The technique involves making small incisions in the cornea, in a radial pattern, which cause it to flatten slightly under the influence of normal intra-ocular pressure: hence it has application mainly to myopia and, to a lesser degree, to astigmatism.
Photo-refractive Keratectomy (PRK)
This more recent development uses computer guided surgical lasers to actually reshape the cornea, in a process akin to sandblasting (photoablation). Although more limited in scope (less good with astigmatism and suitable for a smaller range of myopic errors) this has held out the promise of quicker and more accurate treatment and with fewer complications. It has also gained greatly in catching the public imagination from the sex appeal value of the word laser (have your eyes fixed by James Bond). At the present time there are a number of clinics offering one, or both or these techniques.
RS seems to appeal to people who dislike wearing glasses &co but lack the motivation to do personal work on their vision. The reasons given for preferring RS to, say a course of Bates lessons are generally:
- Bates lessons are expensive
- Bates teachers do not guarantee results
- Bates work demands a certain personal commitment, practice and so on.
On the other hand:
- RS, although quite expensive, is a 'one off investment'
- RS is considered to promise a more reliable outcome
- RS is 'done for you' and does not require the same personal effort.
Let us examine these questions through the publications of the people who use and advocate P.R.K.The essential requirements of any surgical intervention are: safety, effectiveness and predictability. 1
Quite so. Opticians in general are fond of reminding their customers and potential customers of the preciousness of sight and the need to be responsible in the care if the eyes; indeed, one of the standard objections to people working with medically unqualified vision educators is that this may, if not directly dangerous in itself, encourage people not to look after their eyes properly.
We also read, reassuringly:R.K. & P.R.K. methods are well understood because they have been and continue to be the subject of intense scrutiny and research.1
Quite right. So, it's perfectly safe then? Well...P.R.K is effected by lasers which emit ultra violet radiation which removes microscopic portions of tissue from the front of the cornea, altering its shape, and yield a very precise change in its focusing power.
Ultra Violet radiation? Isn't that the stuff that causes cataracts and skin cancer? The one that's so dangerous we mustn't go out in the sun without our expensive sunglasses, and as for that sunning that the Bates people talk about?! Ah yes: but it's been the subject of all that intense scrutiny... Clinical treatment of sighted eyes was introduced in 1988.... for all of five years!
As a candidate for PRK you have to read this document1 which also includes the following items, before signing a declaration that you have read it, understood it, and waive all claims that might arise:Certain side effects are possible.. (including) cloudiness, irritation. subsequent long sight, persistent short sight.. It is understood that the list of complications is not complete
(i.e., the practitioners bear no responsibility for anything that may happen as a consequence, whether or not you were warned, whether or not the surgeon knew about it).
This last point in effect precludes the possibility of any claim for damages for any condition whatsoever that may arise as a result of the procedure. But you've been assured that it's safe, so that's all right.
Anyway, at least it's quick and easy, isn't it? Look, this brochure says:15 seconds.... Laser correction of sight2
Yes indeed:The Laser application only lasts from 15 - 90 seconds
That's the laser application - what else is there? Well, before you get to the laser there is:Surgical removal of the corneal surface will take from 1 - 3 minutes.
That's right, before you get to the high tech laser the front of your eyeball is scraped off with a low-tech scalpel. Ouch: still at least you go home able to see, right?
Well... no, actually, in fact someone will have to take you home because you won't be able to see out of the operated eye at all.A period of 2 - 4 days off work is necessary. Immediate post-operative pain is severe, but is moderated by the application of lubricant and soothing antibiotic ointment and an eye pad.
(That's ordinary severe pain, assuming that the ointment works and the scraped eyeball doesn't become infected, in which case you get the special severe pain).
OK, so it hurts for a couple of days, but then you go back to work and you can see, surely?Vision may be blurred for the first few days or even weeks as the healing processes invariably produce an over-correction (towards long sight) following which normal sight should 1 develop. An interim period of blurred vision may last from 3 to 6 months. The healing process varies from patient to patient and it may take many weeks or even months before the healing process is complete and the second eye can be treated. A difference in focus between the two eyes (anisometropia) will result from treatment of the first eye but its effects may be minimised by contact lens wear in the un-operated eye.
(Bear in mind that if the first eye does not heal to expectation, the second operation will never be done and the imbalance will be permanent.)Outpatient follow up visits are required on a frequent and regular basis in order to monitor the eye for complications and to appraise the refractive result.3 I understand that...it is essential that I attend all follow up visits and adhere to the taking of all recommended medications
(these include antibiotics, steroid drops, painkillers, which are presumably not supplied free).
All right, so it's going to hurt, it has a few risks attached and it's going to be a certain amount of trouble, but at least at the end of it all I'll have normal sight: I mean, with the Bates method, you don't know whether it's going to work or not, do you?...relatively low degrees of uncomplicated myopia (2-6 dioptres) can be predictably neutralised. After one year 92% of treated eyes were within 1 dioptre of the intended refraction1
This doesn't sound too bad, until you reflect that the margin for error is a full 2 dioptres, more than enough to keep many people permanently in glasses and most people feeling dependent on them for driving.
The clinical guidelines document3 quotes a study on 26 eyes (sic - i.e. 13 people) with errors of -1.5 to -6D. The 90% 'success' rate was only achieved with those with an initial error of 2D (i.e. starting with a 2D error you can correct to within 2D accuracy - amazing!) while at -6D (generally considered as the limit for the procedure) the success rate was down to 40%. The number of people, sorry, eyes, with uncorrected vision better than 6/6 (i.e. normal) was 50% of those with an initial <2D error and only 25% of those with initial 6D. Given those figures, the likelihood of two eyes belonging to the same person both ending up seeing perfectly can only be guessed at.
In other words: the procedure, although quick in itself is likely to lead to a period of at least six months of disturbed vision and considerable discomfort, at the end of which one eye only may have 'normal sight', in which case the process can be repeated, or may not, in which case the patient will be left indefinitely with the eyes out of balance.
So: it's not all that reliable: that is, it is almost certain to improve vision to some extent, but it is unlikely to improve it to normal and there is a high probability that one will still need glasses for some or all purposes. It has risks attached that may only just be beginning to emerge, and involves an interim period of complete or partial disability. But at least when it's done, the improvement is permanent?
"After having laser surgery 6 months ago and expecting to have good vision now; I am finding that the eye has reverted to some shortsightedness and I cannot seem to get things into focus. My left seems to be taking over; as I am wearing a contact lens in it and I am relying on this for driving etc. I have the opportunity to have surgery on the other eye shortly, but I have lost faith in this operation now and feel quite desperate about my eyes."
(letter from an enquirer).
It is no wonder then that a long list of those unsuitable for treatment3 includes:...those who are inappropriately motivated or do not comprehend the rationale of treatment Contra-indications: patients with unrealistic expectations or with obsessive, compulsive or perfectionist personalities (i.e. anyone who seriously believes this operation is going to give them perfect sight and is likely to make a fuss if it doesn't) are to be avoided.
The tendency for the vision to regress after an apparently successful operation will come as no surprise since after all, every bit as much as wearing glasses, the operation amounts to suppressing the symptom (the poor sight) without, as Dr. Bates would say, addressing the underlying habit of mind which has caused the problem in the first place. But the point for most of the people who would argue that the operation is 'easier' is precisely that they do not want to alter their habits of mind and it is this that is cloaked in all the excuses about 'not having time, boring exercises' &co.
Coverage of the Question in both the general and professional press is, as would be expected, mixed. Many of the women's magazines and some of the dailies seem to take their copy directly from the publicity brochures and hype the procedure as reliable, cheap, instant and an effort free solution. This is not only cruel, since a very large number of the people who enquire will be deemed unsuitable: too high an error of refraction, unsuitable personality... but also reckless since it creates a frame of mind which is all too likely to sign up for the operation without carefully considering that off-putting small print.
The results of this are brought out by an article in the Sunday Times4 which says, among other points of interest:Studies suggest that up to one in five patients undergoing the treatment is left shortsighted or with worse problems ranging from blurred vision to scarring.
A former Moorfields surgeon, Brett Halliday, is quoted as follows:The history of eye surgery is littered with operations that have been taken up enthusiastically and then abandoned when the long term results are known.
A patient is quoted:At first it was brilliant then, after about a month, the vision in the eye suddenly -went back to where it was before.
A second attempt produced little improvement. She spent £1300 on the operation and an extra £200 on special contact lenses.
That £1300 would have bought an awful lot of Bates lessons, every book ever written on vision education and a few good dinners. To a pupil who would undertake to spend £500 on lessons, attend regularly and follow up diligently all instructions, I think I could just about guarantee that there would be "some improvement in their vision" and that "a proportion may be theoretically treated [by the Bates method as opposed to PRK] to reduce their myopia to a level which would make them at least semi-independent of refractive aids."3
This is as far as the College of Ophthalmologists will go in promising benefit from this expensive and dangerous procedure, yet Bates teachers and other vision educators can expect no end of defamation if they ‘fail’ to produce 100 % success every time, from pupils who (perhaps) cancel lessons, don’t turn up, are too busy to practise etc.
Moreover, I could absolutely guarantee that no harm would come to their eyes, at the time or in the future, and that if it did I would take full professional responsibility.
Despite regular slanders by doctors and others, I know of no demonstrated case where undertaking vision education has done harm, except perhaps to a few people who have caused strain by practising exercises out of books in a wrong way, or in being fanatical about not wearing glasses.
This does not even begin to touch on the fact that with vision education, the improvement in the actual eyesight is, for most people, only a tiny fraction of the total benefit experienced from working in a completely holistic and healthy way with the mind and body, with the connection between the self and the world.
An interesting article in ‘Optometry Today’5 discusses the question fully and concludes:Optometrists should not defend eyeglasses and contact lenses for their own sake. Patients don’t come to OD’s office for eyeglasses or contact lenses, but rather for good vision. If there’s a way to safely provide that to some patients more conveniently ODs owe it to patients to deliver that to them. ODs also need to let go of the academic idea that anything less than 20/20 is unsuccessful correction. Many doctors sniff at the fact that excimers can only get within 1 .00D of emmetropia. Patients who are currently -7.00D myopes would love to be able to see well enough to find their alarm clock, their glasses or contact lenses ...
... to all of which one can only say ‘amen’. But why have your eyes scraped with a razor, burned with a laser, swimming in steroid ointment, and suffer constant pain and disturbed vision for six months just for that when plenty of people get that far after 2 or 3 Bates lessons? Apparently because it’s fashionable, and because there is enough money in the game to pay for lots of convincing advertising and to put together very clever brochures which cover themselves legally by containing all the facts somewhere, while managing to gloss over them and convey a completely false impression that it really is quick, easy, painless and reliable.
At the same time, the feasibility of this technique, with all its uncertainties, underlines the equal feasibility of what Dr Bates proposes. It is obvious that the changes of axial length of the eye required to correct the vision are very small, since only tiny amounts of tissue are removed. (The text book illustrations of the elongated myopic eye are enormously exaggerated). That being so, only very small variations in the muscle balance will be needed to produce the same result, so why not do it that way, safely, enjoyably, and harmlessly and leave the eyes intact? Or is the worship of technology causing more than one kind of blindness?
Since Peter’s article was written, a new kind of laser surgery for eyes has taken over: LASIK: laser-assisted in-situ keratomileusis. In this procedure, rather than burning off the top layer of corneal cells, the surgeon cuts a flap into the top layer of the cornea and the surgery takes place in the middle layer. Afterwards, the flap is replaced, and is assumed to heal back.
There is no long-term study of the consequences of this procedure, because it is less than ten years old. However, some interesting points were made at the US FDA enquiry in April 2008.
Matt Kotsovolos said that he had had the surgery in 2006 and was considered a success based on his uncorrected visual acuity now being 20/20. However, since the surgery he had suffered two years of debilitating and unremitting eye pain. The industry could quote a complication rate of 1-3%, he claimed, only because they did not count night vision problems and dry eyes as ‘complications’ but as ‘symptoms’.
A more accurate assessment probably comes from a study at Ohio State University College of Optometry in April 2007. Their finding was that in 20% of patients, dry eye symptoms were worse or significantly worse than before the operation, and in 15% of patients, night vision problems were worse or significantly worse than before the operation.
Dr Edward Boshnick, an optometrist from Miami, described the failures of LASIK surgery which he had seen. Of several hundred post-refractive surgical patients, the majority who went to him for help had had LASIK, and the majority had had two or more procedures in each eye.
He saw severely distorted corneas resulting in loss of best corrected visual acuity, under- and over-corrections of visual errors, night-time and indoor visual distortions including haloes, glares, ghosting and multiple vision. He had patients who had lost their jobs and were suicidal as a result of this elective, irreversible surgery going wrong.
These are the worst-case scenarios, and for the majority of patients, so far, the satisfaction level is high-ish. But it’s a long way from 100%.
Julia Galvin,. February 2009
1 College of Ophthalmologists: Excimer Laser photorefractive keratectomy; Patient information document 1993
2 Optimax information brochure
3 College of Ophthalmologists: Excimer Laser photorefractive keratectomy; Best clinical practice guidelines 1993
4 Sunday Times 2/10/94: "Laser Eye ‘Cures’ worry surgeons"
5 Optometry Today — Insight: "Will PRK with excimer lasers eliminate spectacles?"
Brett Halliday, quoted in the article, has produced an informative video film on the subject.