Interesting article - Adaptive Optics

Never heard of this before, but it sounds fascinating...

PixelOptics is currently just one of several companies trying to
develop "supervision" for everyone -- including the Department of
Defense

PixelOptics just won a $3.5M USD grant from the Department of Defense
for research to perfect "supervision" technology. The company claims
that it can double the quality of a client's eyesight by using
extremely sensitive lasers capable of detecting the slightest anomalies
on the surface of the eye - then compensating for those defects using
a powered optoelectronic lens. PixelOptics uses electronically
controlled pixels that are embedded inside of traditional eyeglass lens
to bend and manipulate light as it enters the lens.. After the
software makes some adjustments, the pixel will then be programmed to
fix any problems that a person may have.

Since PixelOptics hardware is dynamic, the company also envisions
future systems to adapt to light levels and ambient conditions to
further improve vision. Adaptive optics are hardly a new concept;
researchers and the military have been using adaptive optics on
telescopes and spy satellites to compensate for irregularities in the
atmosphere. Using such small scale adaptive optics for human eyes, on
the other hand, is certainly a new concept that we will see a lot more
of in the future.

 

Scott MacRae, MD at the University of Rochester Medical Center did a
lot of research in adaptive optics as a part of development of
wavefront-guided excimer laser ablations for refractive surgery. They
were able to measure and adjust lower order aberrations (sphere and
cylinder) as well as higher order aberrations with patients.

Interestingly, it was found that when all aberrations were removed and
the patient had "pure optics", the patients subjectively complained of
poor vision quality. Induce some aberrations, and the vision quality
improved. Apparently human vision is designed to accept and enhance
some higher order aberrations.

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 find things like this fascinating, if maddening ;-)

In my case--congenital/infantile esotropia--three subsequent
strabismus surgeries have failed to achieve stable orthotropia or
reasonable stereopsis. The (my) theory is: fusion is a heavily
neurologic process. Though the mechanical alignment may be perfect,
the fusion center may be underdeveloped, providing little 'detent' to
encourage long-term stability in alignment.

Further, the mind has adapted somewhat to seeing a certain way,
providing an apparent tendency to restore alignment to what it finds
most comfortable.

Another example from my story: accommodative spasm. Despite the fact
that I now wear full plus contact lenses--the Rx derived from
Atropinised wavefront aberrometry--and appropriate near-vision add
over-Rx, my eyes still have a dramatic tendency toward pseudomyopia,
even without apparent provocation.

While some of this can be ascribed to ciliary hypertonicity and/or
'instrument myopia,' it's also possible that a portion is due to a
neurologic predisposition--something that refractive surgery, extra
plus, clear lens exchange, etc. likely won't change.

If only I had worn a minus lens ... you know ... at the threshold ....
maybe I wouldn't have developed this stair-case hyperopia.

Sigh.

 

Picture the use of such technology to correct post surgical eyes with
suture-induced High-order aberrations like trefoil. Almost guaranteed
such patients would prefer to get rid of the aberrations.

 

If only I had worn a minus lens ... you know ... at the threshold .... maybe I wouldn't have developed this stair-case hyperopia.

Hey Neil - *WHAP!*

 

posted a reply but it didnt show up so heres it again. high order
aberrations prevent the eye from seeing its best. I get 20/30 with
conventional glasses. Looking forward to 20/15 or even 20/10!

 

By the way, I have more to say!


http://www.dailytech.com/article.aspx?newsid=693


a recent article about how adaptive optics may be materalizing! Imagine
glasses that correct your higher order aberrations too! I have the
feeling alot more people will be wearing glasses, even those seeing
20/20 when they find out what 20/10 is like! Suddenly those 20/40 very
low myopes that dont bother with glasses because it doesnt make much of
a difference will suddenly embrace glasses because now that their high
order aberrations get corrected in addition to their refractive error,
they will really see clear!

I have the feeling millions who got laser or other refractive surgury
will be disapointed to be back in glasses in order to enjoy good, crisp
vision. All forms of refractive surgury, especially laser induces more
aberrations so they arent seeing as good as they should. I can see RS
being alot less popular because it cant give you vision as clear as
conventional glasses, much less wavefront glasses! If someone was given
the choice of getting 20/20 with lasik or 20/10 with wavefront glasses,
almost all will choose wavefront glasses! Lasik would be a complete
waste for me since ill still need glasses to see clearly and may in
fact also need reading glasses.

 

One more comment: I read that true wavefront glasses needs to be
dynamic because your eyes are constantly moving and shifting focus so
youll need glasses with tiny sensors that follow your every eye
movement. Stationary wavefront only works if you keep your eyes
perfectly still and centered so they align with the aberrations. We
need something that follows the movement of your eyes to keep the
aberrations aligned at all times. This poses many technological
challenges and may be some 15 to 20 years away from reaching the
market. There already is (stationary) wavefront glasses out but my
friends say 9 out of 10 people see no difference or they actually see a
little worse! The 1 in 10 who do see a difference have a large number
of aberrations, usually from a bad lasik experience. One guy had lots
of glare and his wavefront glasses reduced the glare.

 

hyperopia is an eye that failed to fully complete emmetropization.
Almost everyone starts out hyperopic in their infancy and early
childhood. I went thru emmetropization too far and ended up myopic.


As for adaptive optics, its the ticket for anyone with a number of high
order aberrations like me. Conventional glasses cant compenstate for
this so I fall a little shy of 20/20 at 20/30. I really wonder what
20/15, or even 20/10 vision looks like! This will also be great for
those post-lasik patients who had their aberrations increased and dont
see well, especially at night.

 

I pinhole to a full 20/25 and I can almost see the 20/20 line but its
too small because of my minus glasses which minify. Because alot of my
aberrations are located on the center, the pinhole cant help me 100%.
With tomorrows glasses I may be like 20/15 WITH minification(which
would make me a little better than 20/15 in fact) I also got
topographies and have already been commented by several about my
aberrations and astigmastim. The fact pinhole makes a difference is a
good indicator my limit is optical. Wavefront glasses work better than
pinhole. By the way about a third of people cant correct to 20/20, not
even with contacts.

 

Dear Central,

In fact, there is a "school of thought" (i.e., second opinion) that
when a child's refractive state is +3 or so (and he is young
and "adaptive) the "plus" should be kept off his face, until
his eyes "adapt" down to a normal zero to +2 diopters.

On a optical control-system the effect of putting a +3 on
a child at +3 diopters, is that his refractive state
will not only stay at +3 but will "move positive" -- as
was the case for Neil Brooks.

There is no "magic pill" here -- just an honest difference
of opinion.

But, "Central" many a truth is said in jest.

Best,

Otis

 

By the way, I have more to say!

we all wait with baited breath to hear what aceman has to say.

 

Dear "Central",

Subject: Adaptive optics -- Adaptive Eye to A lens.

Re: The second opinion on the plus lens.

Looks like you were correct about Neil Brooks. An over-prescribed
plus can certainly make a monkey-primate eye "more positive".
It is possible that the same "adaptiveness" also occurs
for the human-primate eye.

Dr. Allen supports the second-opinion which is to "go slow" about
putting a young child in a full-strength plus lens.

You suggestion about stair-case hyperopia is correct.

Best,

Otis

==========================



How to Eliminate Hyperopia

(A HIGH positive refractive state of the fundamental eye.)

by Merrill Allen, OD, PhD, FAAO, FCOVD

PROFESSOR of OPTOMETRY

Indiana University.

Summary: The young eye should be given time to move towards zero
diopters refractive state (emmetropiia). A strong plus
lens will interfere with the "normalization" process
(i.e,, interfere with "emmetropization".) This statement
is the "second-opinion" by a highly qualified experts.


Re: When I'm in the mall, I see thick glasses on small children
and I have to control myself. I know that wearing those
glasses blocks emmetropization. (i.e., blocks the
process of normal vision growth. Subsequently, a
proven characteristic of the primate eye. OSB) If Mom
would put the glasses on the child only in the
afternoon, the child would grow out of his/her hyperopia
and require several spectacle power reductions. If the
child's correction is less than the refractive error,
he/she will grow out of the need for those glasses and
soon weaker lenses will be needed. Dr. M. Allen


__________________________________



Humans are adaptable. The refractive error distribution in
the population of newborns is almost a normal curve. By the first
grade the distribution has become leptokurtic with the great
majority of the population falling within -0.5 and +2.00 diopters
of error. The babies have grown out of their refractive errors!

Graduate Students at Indiana University did a study of babies
at 2 weeks of age who performed as well on focusing tests as
college students. The one baby who did not was about 5 D
hyperopic. After 6 weeks or so it was clearly withdrawn and
abnormal in personality. The baby could not respond to the test.
Application of +4 D glasses changed the baby's personality
overnight! Regarding the overcoming of hyperopia by optometric
intervention, the baby above was not followed, but if the baby
continued to wear those glasses, now as an adult, he/she will
still be +4 hyperopic.

I worked with an 18 month old esotropic girl whose eyes were
so crossed I thought she had convergence fixus. However when I
held her at arms length and turned my body through 360 degrees her
vestibulars took over and her eyes straightened and she showed
nystagmus. At each of the three visits I increased the plus to
take home. Her eyes straightened with +11D. Then at the age of
three years while moving to another city she lost her glasses and
went without them for 3 months. The new eye examination showed
her Rx to be +4. She had lost 7 diopters in three months!

I did not realize the significance and was not smart enough
to say to Mom: "Let's leave the glasses off for another 3
months," or "Let's wear plano glasses with binasal occluders for 3
months." The last checkup of this patient was at age 18 years when
she was wearing +4D contact lenses! We cured her of esotropia and
reduced 7 diopters of hyperopia! She has of course continued to
be straight eyed.

Wild monkeys have low hyperopia or emmetropia and no myopia.
Caged monkeys have less hyperopia and much more myopia. Because
the evidence for emmetropization is so strong, I suggest a couple
of approaches on how to emmetropize young hyperopes.

Only prescribe as much plus as needed to keep the eyes
straight. (In the case of our baby that couldn't focus and had
personality problems, the plus probably wouldn't be needed for
more than a week or two as the child figured out how to use his
eyes.

At most the Rx should only be about half of the retinoscopic
Rx and then reduced in power as the eyes change. With esotropia,
more plus power may be needed at first to establish normal
binocular vision, after which treatment of hyperopia may proceed.
Alternatively for esotropia, the no Rx, binasal approach, see
below, is highly recommended. Use no lens power but provide
binasal occluders such as frosty Scotch tape applied with the
outer edges placed at the distance apart of the centers of the
pupils, minus 4mm.

A growing child will require frequent occluder adjustments as
his/her pupillary distance increases. The binasals will
straighten crossed or exotropic eyes as well as cause
emmetropization. Within 6 months the occluders can be removed.
Strabismus and refractive error should be cured in that time! if
you or the parents forget, the child will grow out of the binasals
[they will cover less and less of the visual field] and will be
cured.

We know that older people grow into myopia, so I would not
put an upper age on when a person can grow out of hyperopia. The
important condition is that they be able to intensively pursue
visual tasks requiring accommodation. If they are not visually
involved, and if we eliminate the need to emmetropize, they will
not emmetropize!

When I'm in the mall, I see thick glasses on small children
and I have to control myself. I know that wearing those glasses
blocks emmetropization. If Mom would put the glasses on the child
only in the afternoon, the child would grow out of his/her
hyperopia and require several spectacle power reductions. If the
child's correction is less than the refractive error, he/she will
grow out of the need for those glasses and soon weaker lenses will
be needed.

 

What is ... the threshold, Alex?

 

Wow, I was scanning (read the first 3 or 4 words
every 10 or 20 lines) and this came accross as

=Quick

 

Dear Quck,

That was Dr. Allen's statement. You should read
the complete paper to understand what
the man was saying -- rather than skimming
and not having a clue.

The majority opinion is indeed to put a full-strength
plus lens on a child (like Neil). Dr. Allen was
suggesting a "go slow" process because the
eye is indeed "adaptive", and a full strength
"plus" will result in the eye moving in
a positive direction.

Allen simply "objected" to that majority-opinion.

Best,

Otis

 

How could one tell from your post?

 

Glenn

http://www.stronghealth.com/services/strongvision/aboutsv/MacRae.cfm

I have small belief in words if they are said RS surgeon

Glenn ,What symptoms rather "poor vision quality" ???

These researches are in an initial stage. Why you present it as " the
obvious fact "???

Ace 20/20>20/15>20/10
It is similar: in a computer the graphic editor do " sharpen filter "
at processing a photo.

Ace

You can try good RGP lens.
Why you cannot come to dr. Leukoma???
I am assured that DR will give you greater discount in the price as you
are " the expert of sight "
You dont have time and money for travel to dr. Leukoma???
Problem-money ???

 

I wish to correct.
I have small belief in words if they are said RS surgeon
And especially in unsubstantiated interpretation Glenn H

 

Glenn, can you post the reference? Not to argue about the finding about
how the eye/brain deals with high-order aberration (which I have no problem
with), but I'd like to know whether the aberrations were removed optically
at the bench, or with photorefractive surgery. I think some people might
be getting the wrong impression.