A little survey about halo in LASIK

I don't know if this is going to get reliable results, but I'll try anyway.
I do hope that there will be many truthful and accurate answers.

If you had LASIK (or other refractive surgery, but mention about it if it's
other than LASIK), you are most welcome to participate in this survey. This
is just for informative purposes.

1. How long since you had the (first) surgery?

2. Do you see distortion of any kind, in daylight or in dark? If you answer
No, you can stop the survey here, but add a comment about your vision (be
critical, show that you do pay attention to visual quality).

3. Do you see disturbing starburst around small/distant lamps at dark?

4. Do you see disturbing halos around bigger/closer lamps at dark?

5. Does the starburst/halo size around lamps change when the pupil size
changes? If yes, does the halo reduce to zero or practically almost zero
(you can test this for example by looking out a window at night and then
constricting the pupils by the use light, eg. flash light)?

6. Has your starburst/halo size or brightness changed after surgery? If yes,
please tell how did you measure this (looking at the same lamps month after
month from the same spot can be a good test).

7. Do you see a less blurred image if you look through "finger binoculars"?
Roll your index fingers and look through the small holes formed. Look at
something in room illumination with high contrast, for example a black
poster with white text or a white object on black background.

8. Do you have difficulties recognizing faces if the person is standing in
front of a bright window -- or do you see everything more or less foggy in
room illumination?

9. Your happiness about the result (0-100%), where
- 100% = aquity is 20/20 or better, there are no side-effects
and any distortion is totally non-disturbing
- 50% = some disturbing side-effects, you don't have to
worry about glasses anymore, but the vision is far from perfect
- 0% = major difficulties at reading and recognizing faces,
driving a car at dark is hazardous (or other complications).

10. Your pre-operative prescription, dilated pupil size, perfect correction
optical zone size and transition zone size (if you know them). And your age,
if you wish.

X. If you have something else to comment about your vision, please add it
here.

Thank you very much for your time and effort!

 

Here are my own responses to the survey.

1. How long since you had the (first) surgery?

3 months.

2. Do you see distortion of any kind, in daylight or in dark?

Yes, in dark. Bright daylight is better than pre-op with spectacles.

3. Do you see disturbing starburst around small/distant lamps at dark?

Yes.

4. Do you see disturbing halos around bigger/closer lamps at dark?

Yes.

5. Does the starburst/halo size around lamps change when the pupil size
changes?

Yes. It reduces to almost zero when the pupil is about 5.0mm or so. The
maximum starburst diameter is quite big and it's very bright too (covering
cars behind it etc.).

6. Has your starburst/halo size or brightness changed after surgery?

Not at all (since two days after surgery my vision has remained the same).
I've measured my distortions for example by looking out of my room window at
two lamps. Their starburst max. diameter is now the same as it was before
surgery without glasses (the two starbursts are just touching eachother when
they're at maximum).

7. Do you see a less blurred image if you look through "finger binoculars"?

Yes, I see a very sharp and stable image by looking that way.

8. Do you have difficulties recognizing faces...

Yes.

9. Your happiness about the result (0-100%)

50%.

10. Your pre-operative prescription, dilated pupil size, perfect correction
optical zone size and transition zone size (if you know them). And your age,
if you wish.

-4.75 both eyes (-0.25 astigmatism), 7.66mm (horizontal), 6.0mm and with
transition zone about 8.2mm. Age is 26.

X. If you have something else to comment about your vision, please add it
here.

I don't have any severe complications or side-effects other than this
starburst/fog problem. I use eye drops very rarely anymore (dryness is not
severe anymore). I can't see as near as I could anymore, the limit is about
10cm now.

 

Pauli's survey will undoubtedly be interesting, but is under no
circumstances going to be representative of reality. A voluntary
survey without any controls in an unmoderated newsgroup is not likely
to accurately represent the actual reality of all refractive surgery
patients or carry much statistical merit. I guess it is time to post
again my....

LURKERS, SEARCHERS, and HAPPY CAMPERS

How about a statistical fact:

98% of all pedestrian vs. auto accidents occur when the pedestrian is
within the crosswalk.

Now a statistical analysis:

Crosswalks are the most dangerous place for pedestrians to cross the
street.


If you conclude by the posts on the refractive surgery related
bulletin boards and newsgroups that this industry has nothing but
problems, you are making the same mistake as assuming crosswalks are
the most dangerous place for a pedestrian.

People posting on bulletin boards tend to be one of three kinds of
researchers.

One group is researching before making a decision about refractive
surgery. The information this person needs is readily available if
they read enough posts. They may never post a message. These are the
Lurkers. BTW, Lurker is not a derogatory term.

Another type of group using bulletin boards and newsgroups is looking
for answers to unresolved problems. They post very specific items and
watch the board closely, looking for someone who also has their
problem that may have found relief. These people are dissatisfied
with the results of their surgery and may even feel they have been
wronged. Often they will post warnings to others who may be unaware
of the potential for problems like the ones they suffer. These are the
Searchers.

The last group using bulletin boards and newsgroups are delighted with
their refractive surgery and other than "thanks" don't have much to
say. These people may even feel a little guilty about posting their
satisfactory results amongst so many people who are experiencing
difficulty. These are the Happy Campers.

This presents a skewed representation of the refractive surgery
public.

Our organization has determined from multiple sources that about 3% of
refractive surgery patients (all types of surgery, all types of
refractive error) have an unresolved complication at six months
postop. About 0.5% have a serious complication that requires
extensive maintenance or invasive treatment to resolve/maintain.

The posts on these boards are almost exactly the opposite - around 97%
about problems and around 3% about successes.

The information about problems relating to refractive surgery is very
important and all possibilities must be considered. It is also
important not to draw the wrong conclusion when adding up the quantity
of information about problems and the quantity of information about
successes.

Glenn Hagele
Executive Director
USAEyes.org

"Consider and Choose With Confidence"

Email to glenn dot hagele at usaeyes dot org

http://www.USAEyes.org
http://www.ComplicatedEyes.org

I am not a doctor.

 

I totally agree with that.

And I disagree with that one. Inherent in your organization's
presentation of the numbers are two issues:

1. you have a vested interest in promoting refractive surgery. I will
add that unlike some similar groups, you do indeed present both sides of
the issues and do so with patient's best interest as a real concern, an
admirable quality.

2. It is also well known that refractive surgery patients with less than
stellar results, as in Paul's case, are more likely to "hide" their
complaints. They do this as a psychological protection against the
unresolvable depression or regret they feel having altered their body
with negative outcome.

That being said, do we really know the actual number of patients that
have life-altering issues following refractive surgery?

--LB, O..D.

 

Actually, if anything, Glenn reflects a negative view of LASIK. His
3% number needs to be revised and lowered. I don't understand why the
anti-lasik people attack him so much. They aren't going to ever get
someone else to give a seemingly credible negative view of lasik.
His infomration is extensive and right on. but his statistics are
skewed, and his personal opinions are off the mark. One way to read
his posts is to think of them as the most negative slant you could put
on real facts. The opposite of that would be the sleazy marketers who
put the most rosy, positive slant on the facts without being blatantly
false.

 

Thank you Glenn for your good analysis on the message board behaviour. I
agree (and I have thought about this before). It is a difficult thing to
make accurate statistics, even for an honest doctor who is making statistics
of his patients. Most of the patients do not know how to accurately describe
or measure their problems (but with proper methods it should and must be
possible to make accurate statistics!).

With this survey, which I hope even some people could take the time to
answer, success rate statistics will not be accurate. But, as you might have
guessed, my topmost interest is actually the healing process: is it true or
is it a myth. With the information delivered within the questionnaire
answers I hope to understand the healing process better. And it would be
interesting to find out if new relations of things would occur. But that
would require hundreds of answers which is of course utopia. For example, it
seems that the older you get, the smaller the scotopic pupil will be - does
the age of the patient affect halo occurances?

 

There is one very important difference: Our organization has no
financial incentive for anyone in particular to have or not to have
refractive surgery. The doctors we certify certainly do, but we don't
make anything if someone does or does not have surgery with a
USAEyes.org certified doctor or anyone else.

So long as refractive surgery exists in one form or another, the
information and services we provide will be in demand.

That said, I'm sure that some of the doctors we have certified would
not be so interested if they did not reasonably believe that our
certification got them more patients. To be very frank and honest,
I'm delighted if someone selects a USAEyes.org certified doctor. That
means they are selecting someone who is at least independently
evaluated. I'm pretty happy when someone uses our 50 Tough Questions
For Your Doctor too.

In comparison, the ASCRS LASIK guidelines has a very troubling "less
than one percent" complication rate statement. But then ASCRS is an
ophthalmology trade organization.

Thanks for the (very) limited endorsement. I'll graciously accept
whatever I can get. 8^)

I don't think there is much anyone can do about people who don't
report their outcomes truthfully. But wouldn't you say that goes both
ways? For those who over-report problems as well as those who
under-report them.

Glenn Hagele
Executive Director
USAEyes.org

"Consider and Choose With Confidence"

Email to glenn dot hagele at usaeyes dot org

http://www.USAEyes.org
http://www.ComplicatedEyes.org

I am not a doctor.

 

It's not *that* limited. I really do believe that your replies are well
thought out, well written and provide a degree of honest presentation
that is, at least in these part, very, very lacking in the RS business.

It really bothers me to hear day after day radio ads promoting this or
that doctor as the "premier surgeon" "now with blah blah laser that can
give you better than 20/20, even better that 20/15!" and you know the
rest of BS come-ons.

Sure. But the real issue for me is people who had RS and live a life of
constantly looking for a fix to their problems, or have problems that
seriously disrupt the quality of their lives. Or, as for one person I
know, loose their job as a direct result of LASIK. But equally
important is the problem of potential RS patients having an unrealistic
view of what will be. And, of course, the scams and doctors with less
than stellar ethics.

I'm glad that you are trying to deal with those issues. So thanks for
that. Nevertheless, there remains an industry-wide problem and one that
causes far too many people to live with a life long (hopefully not!)
disability.

--LB, OD

 

I disagree. I think the true value is somewhat higher. There are a lot
of post lasik people out there who don't complain because they see so
much better without lenses than they did without lenses pre-operatively,
they feel sheepish even mentioning their little "problems".

For example, a common case would be a 4 D. myope.

20/400 unaided before surgery (20/15 with glasses or contacts).

Post LASIK:

Unaided acuity
R 20/20-
L 20/25+

Now refracts as plano O.U., and 20/15 is now not possible.

So the guy/gal is now able to drive without glasses/contacts, and is by
the numbers a success, one of the 97%, right?

Wrong.

This person will never again see 20/15. He/she won't complain, or if
so, will be told that the numbers are great. Better than expected. This
person may even believe that they have a great result.

Sorry, but I like 20/15, and I like not having to strain to read it.

w.stacy, o.d.

 

No one has survived long enough post-lasik to know that, Pauli.

 

1. How long since you had the (first) surgery?

7 years

50% - although I am completely happy with my outcome and have NO regrets

-14/-18, BCVA 20/40

 

As I recall, the literature for the VISX Customvue system claims that
90% of their standard lasik patients get 20/20 or better. With their
customvue LASIK - 99% get 20/20 or better, and 75% get 20/15 or
better. If that's not good enough odds for people, don't have lasik.

One thing I don't think you are considering is that in your case, you
have the luxury of unlimited eye exams and also the luxury of trying
out every contact lens availble to find which ones are best for you..
and you replace them more often than a patient would.
I recall that when I wore RGP contacts, I needed a new set. The OD
changed brands on me from Hydrocurve 3 to some B&L lenses. The exact
same Rx and size in B&L were problematic, so I had them changed to
Hydrocurve 3 and they were much better. How many people would be
lucky enough to get lenses to work well with their eyes?

 

No one has survived long enough post-lasik to know that, Pauli.

According to this:
http://www.opt.uh.edu/research/voi/WavefrontCongress/2004/presentations/27BRADLEY.pdf
(page 9), the scotopic pupil would be 0.5mm smaller in 10 years. It should
be possible to measure the effect of that. Also that (slightly inconclusive)
chart would suggest, that people over 50 years should clearly have lesser
large pupil related problems (but of course, many studies suggest that large
pupil is not a risk factor in the first place which is the first oddity I'd
like to dig into).

 

The odds are that you will have additional changes in your refraction
by the age of 50 anyway. Myopes tend to become less "short-sighted" as
they get older (pun intended).

In your further digging, you will undoubtedly find that many studies DO
NOT suggest that pupil size is NOT a risk factor in the first place.
The few studies suggest that pupil size is not the only risk factor
after 6 months with pupils up to 7.0 mm in diameter. The main
criticism of the Schallhorn study -- and others -- is the lack of
inclusion of very large pupils in the data.

I just dispensed a pair of contact lenses to a patient yesterday. His
pre-operative prescription was -8.50, with large pupils. Decentration
is slightly superiorly. Patient has slight residual refractive error,
including irregular astigmatism. BCVA is 20/25 with spectacles.
Corneas are just barely thick enough for an enhancement. Should he
have had LASIK?

The contact lenses completely eliminate the starbursts, for which he is
very happy. I am certain that wavefront would reveal a dramatic
reduction in spherical aberration and coma, as it has in other cases.
The optical zone on the contact lenses is 8.5, with a 0.8 mm blend zone
on either side. Previous lenses with 6.5 mm optical zone did not
completely eliminate the starbursts.

BTW, post-RS patients are often delighted to find that contact lenses
after LASIK aren't nearly so uncomfortable as they anticipated. This
is due to the relatively large size of the lenses as well as
post-operative corneal hypoesthesia.


DrG

 

So you probably believe in fairies, too. Or do you simply believe
everything is true as long as it's in writing? Duh! 99% 20/20 is
ridiculous. Unless, of course, you achieve the ability to read the 20/20
letter size through the ghosts, haze and higher order aberrations with a
little bit of squinting, just the right light level to compensate for
the loss of contrast and, of course, one letter at a time. Not
real-world sharp and clear 20/20. Fabricated.

Duh. Hydrocurve is a SOFT LENS, not RGP. We really can trust what YOU
write, eh?

That's why we have dozens of lenses to choose from, not one-size fits
all.

It's not luck. Oh, I'd say 99%----or they wouldn't be wearing them, or
could choose another type or none at all and back to specs. Get LASIK,
doesn't work out, there's no going back.

--LB, O.D.

 

You may be guilty of doing what many people have done, and that is to
interpret the findings of Schallhorn et al to say that pupil size is
not a risk factor. That is not the findings of these studies.

The studies by Schallhorn and several that have followed have shown
that pupil size alone is not a reliable predictor of night vision
problems after refractive surgery. The distance between "not reliable
predictor" and "not a risk factor" can be measured in light years.

What Schallhorn affirmed, and nearly every knowledgeable observer
already understood, was that night vision problems are multifactorial
and are not only caused by an imbalance in the optical ablation size
and the naturally dilated pupil size. Several other factors are
involved, including amount of refractive error to be changed, depth of
ablation, percentage of cornea ablated, angle of transition zone, and
undoubtedly much more.

Observers have always known that some people with large pupils and
small optical ablation zones don't get halos. Schallhorn's study
affirmed this.

Pupil size is important, even if it pupil size alone is not a reliable
predictor of night vision problems.

See http://www.usaeyes.org/faq/subjects/lasik_pupil_size.htm


Glenn Hagele
Executive Director
USAEyes.org

"Consider and Choose With Confidence"

Email to glenn dot hagele at usaeyes dot org

http://www.USAEyes.org
http://www.ComplicatedEyes.org

I am not a doctor.

 

You scare me Larry.. I hope your not really an OD.. but I fear you
are. One crucial thing you failed to mention is that the Snellen
20/20 designation is primarily an opinion of an eye doctor. The
combined vision of both eyes is generally better than either eye
independently.
Although I think the VISX data of 99% or better with 20/20 vision with
Customvue is accurate, it should be noted - which I failed to do
earlier - that during the time period when that data was taken,
Customvue was only done on "ideal" patients which is only about 50% of
LASIK candidates. Up until about a year ago, Customvue was not
available to the other 50% of more problematic patients (it is now).

Your garbage about ghosts and haze and HOA is just that.. garbage. I
can promise anybody of moderate to severe myopia that the
complications of contacts are much more significant that any LASIK
complications. Another naughty thing that LVI does is it does LASIK
on patients of very low myopia - if it ain't broke, don't fix it...
LVI's criteria to be a patient is to have a pulse and a credit card.

I don't know where you went to school, but squinting isn't going to
affect ghosts, haze or contrast issues.

You got one thing almost right... I made a mistake about the name of
the new brand contacts that I had prescribed about 14 years ago. I
had BOSTON rigid lenses which worked quite well, then decided to try
the Hydrocurve 3 TORIC lenses (hardly a typical soft lens) that were
advertised to be great but were worthless. Then the doctor put me in
B&L rigid lenses which were not so great.. and finally wound up back
in Boston rigid lenses.
This brings up another issue.. there are so many brands and types of
contact lenses that no doctor can possibly stock even a small fraction
of those available. Just about every brand and type of lens has it's
own unique characteristics and the same Rx with a diiferent brand or
type often has radically different effects.

You can go crawl back into your hole Larry. And it's probably a good
idea that you don't identify yourself.

 

What were you smoking today cliffy?

Quote "One crucial thing you failed to mention is that the Snellen
20/20 designation is primarily an opinion of an eye doctor." Sorry
cliff, 20/20 is the line the patient can read. It is standardized so it
is a repeatable measure.

QUote: "Your garbage about ghosts and haze and HOA is just that..
garbage. I
can promise anybody of moderate to severe myopia that the
complications of contacts are much more significant that any LASIK
complications" You are an expert making promises now?? Contacts can be
removed, Lasik can't.

Quote: "I don't know where you went to school, but squinting isn't
going to
affect ghosts, haze or contrast issues." Yes it will. Reducing pupil
size will alleviate off axis aberrations such as ghosting, haze and
reduced CS.

Quote: " I had BOSTON rigid lenses which worked quite well, then
decided to try
the Hydrocurve 3 TORIC lenses (hardly a typical soft lens) " Actually
a very typical soft lens, crappy design, crappy material, but standard
for the time.

Quote: " Then the doctor put me in
B&L rigid lenses which were not so great.. and finally wound up back
in Boston rigid lenses. " Actually, cliff, B&L own Boston (Polymer
Technology) and have for years. B&L lenses were made from Boston
materials.

Quote: " This brings up another issue.. there are so many brands and
types of
contact lenses that no doctor can possibly stock even a small fraction
of those available." This is where a thing called experience comes in.

Quote: " And it's probably a good idea that you don't identify
yourself. " Just like yourself???

If you are going to flame legitimate optometrists who visit here with
your usual vitriol cliff, could you at least get your facts straight.
Currently you're bgatting at 0.0

dr grant

 

You may be guilty of doing what many people have done, and that is to

The finding of this study

http://www.ncbi.nlm.nih.gov/entrez/...ve&db=PubMed&list_uids=14711706&dopt=Abstract

is that "pupil size was not a major risk factor of NVCs throught the first
postoperative year".

What I'd like to add here is that I think that a patient's NVCs could
probably be classified and that transition zone (or non-ablated zone)
induced NVC could be measured as it's own phenomenon. Larger pupil does
unmask more aberrations than just the transition zone problem, but I don't
think it strenghtens the aberrations in the central zone, it just exposes
more non-perfect surface and that reduces the quality.

Perfect correction ablation diameter, prolate, oblate, "angle of transition
zone"... Why are those things so controversial. I realize that because of
the limited amout of stroma to be ablated the optimal, patient-dependent
ablation pattern has to be mathematically calculated and can not be perfect.
And there are different mathematical optimization algorithms. But isn't the
angle of transition zone very unambiguous. If it is mathematically
refracting elsewhere than the perfect correction zone is refracting, then
that's what it will do.

Note that I'm NOT saying that the transition zone is the only cause for NVC.
Probably even the best human eye sees certain kind of starburst/halo on
extremely bright objects (even without the squinting induced effect).

 

Pauli. Don't believe everything you read in an abstract. If somebody
concludes that pupil size is not significant, read the entire paper.
Recently, I quoted the conclusions of a study involving Intacs and
keratoconus. The study used a sample size of 13. One out of the
thirteen resulted in a failure, and yet the study concluded that the
treatment was not only efficacious, but safe. That is statistical
insanity.

I also read a study, published in The Lancet in 1999, involving
thousands of patients wearing contact lenses. The study found that
1/500 people who slept in their lenses developed infectious keratitis
per year using old technology. OK, that's not good, but of those, less
than 15% suffered any permanent detrimental effects to their vision.
Yet, the study concluded that sleeping in lenses is unsafe. That is
also statistical insanity.

I am seeing more and more patients taking their refractive surgeons to
court over halos and starbursts. Stupid, stupid, stupid.

DrG