Explanation of some optical effects after cataract?

I recently had cataract problems and surgery to correct for them. After the
surgery, I noticed some optical effects that I cannot completely explain. I
am pretty sure that both optics and eye anatomy are involved. Posting on
sci.med vision did not produce answers that gave me a satisfactory
explanation.

The newly operated eye with an intraocular lens implant produces multiple
images, maybe six or more, of a small source such as a traffic light at a
distance or an LED indicator across a room. The darker it gets, the larger
the pupil and the greater the number of images. It is fairly obvious that
much of the effect occurs from light entering near the margin of the eye's
pupil. Blocking off of the pupil with a finger in front of the eye gets rid
of some of these images. It is as if the cornea was a series of flat
sections instead of spherical, each providing their own image. That is, it
does not appear to be something like spherical aberration.

My ophthalmologist said not to worry. Wait until I don my new glasses. I
really do not understand how spherical and cylindrical corrections will get
rid of multiple images. Nevertheless, even before the surgery, I had noticed
that without glasses, an object like mars looked like a frozen-in-time
firework star burst. Putting on the glasses merged all these images into a
single somewhat fuzzy image. At the ime, my glasses did not give complete
correction.

Another phenomenon was observed as I looked at numerals on a license plate.
They would shimmer with slight head motions. I attribute that to a moire
interaction between relatively transparent but refractive floaters and the
real image of the license plate formed a few millimeter in front of
(anterior) to the retina. I do not know if that is the correct explanation.

Most of my reason for asking is that of intellectual curiosity. Of course,
if my new glasses do not improve those aspects of my vision, I will take a
greater subjective interest in what is happening.

In addition to explantion, I would like to get suggestions on what else to
observe.

Bill

 

Here is my prediction:

given the fact that your symptoms are clearly symptoms of mental strain,
it will be VERY DIFFICULT that your new glasses will solve the problem.

My bet is that they WON'T solve anything.

All that you can do is just get accustomed and forget the whole thing.

On the contrary, if you are intelligent (a fact which has to be proved),
you can really start a great journey into the mysteries of vision and
understand slowly slowly the root of all of your problems.

Once you understand that, you will be pushed forward by your very self
to achieve perfect vision, 20/10 in all situations.

Perhaps you will stop at 10/10 or 5/10, just to get your driver's
licence. But this will be a great victory over the wrongdoings of your
past self and of the wrong science that the professionals here are
merchandising for their own vested interests.

--
Please visit
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and you can buy a replica of the Original Dr. Bates book
"Perfect Sight Without Glasses"
and if you are interested, join the group
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<snip>

I may have mental problems, but compared to you, my mental status is
perfection indeed. I am not looking for responses of the kind you posted. I
possible please kill file me.

Bill

 

A man who thinks of killing has obviously mental problems.

 

I don't know much about the details of your surgery: what was the
incision pattern through the cornea? How much of the lens was removed
and replaced? How was the implant prescription determined?

Are the effects you described (Mars, license plates) the same, worse
than, or better than what you observed pre-surgery?

 

Andrew Resnick wrote:

Mr. Resnick,
you working at NASA may verify this information: it is said that
astronauts in space with perfect sight can see the equivalent of a small
tennis ball at 3,000 meters distance.

Is this a true statement from NASA?

thanks.


--
Please visit
http://www.stores.ebay.it/juppiterconsultingrishi
and you can buy a replica of the Original Dr. Bates book
"Perfect Sight Without Glasses"
and if you are interested, join the group
http://health.groups.yahoo.com/group/PerfectSight/

 

A 6.5 cm diameter tennis ball will subtend 4.5 arcseconds at 3000 meters.
I do not know what 20/20 vision is capable of resolving, but I believe
it is approximately 1 arcminute. Thus, the tennis ball is below the
resolving power of the eye.

Given suffient contrast between a bright object and dark background (or
vice versa), it is possible to detect objects (power lines are a good
example) that are below the resolution limit.

The eyeball's shape will change a bit due to lack of bouyancy, but I
suspect the effect is to degrade optical performance, given the role of
the brain in vision. Effects during launch and landing can be quite
severe.

 

I do not know most of these details. The implant is a spherical correction
although there is significant astimatism. The value chosen was to match the
other eye which had an implant several years ago.

It is hard for me to tell because there is no side by side comparison. I am,
however, pretty sure that the license plate effect is a moire effect.

Bill

 

Thank you very much indeed.

--
Please visit
http://www.stores.ebay.it/juppiterconsultingrishi
and you can buy a replica of the Original Dr. Bates book
"Perfect Sight Without Glasses"
and if you are interested, join the group
http://health.groups.yahoo.com/group/PerfectSight/

 

It might be helpful to know if you had the stitch-less cataract surgery where
the lens is ultrasonically pulverized and removed with a vacuum thru a tiny self
healing incision or the one where the larger incision is made and the lens
pulled out intact. The latter has been known to produce more artifacts. Implant
precriptions are often derived from either ultrasonic or laser measurements and
a formula that your surgeon uses based upon past experience. Your doctor should
be able to provide the answers if you don't know. Also, generally speaking,
implants do not correct for astigmatism. But research is continuing in this
area.

George

 

Research is being continued in the wrong direction, unfortunately!

 

Go to:

http://www.surgicaleyes.com/

I believe that you will find similar problems it the radial
caritometry (spelling error no doubt) field. Scar tissue changes the
refractive index of the lens/cornea ... and can cause the effects you
have observed.

Donald Janeczko

 

That site covers a different subject.

Changes at the lens or cornea can produce multiple or smeared images. In
that respect, I wonder how they can form polyhedral surfaces. That is a
combination of flattened regions.

As far as moire effects are concerned, they would arise whenever two light
structures of similar variation are superimposed. An obvious example is
provided by a window screen and its shadow. I am hypothesizing that my moire
pattern is formed by overlap of a real image (licence plate) with a index
varying floater. It is possible that it is a spatial interference between
the floater and the diffractive interference pattern formed by anomolies in
the shape of the lens or cornea. I am hoping that someone who *really knows*
can provide sufficient information to end my speculation. I prefer not to
have more speculation piled on top of mine.

Bill

 

Multiple images are a symptom of mental strain.

I suffered very much of them, expecially after having discarded my
contact lenses in 1989/90.

for example, by looking at a black chart with white letters, I do not
have any multiple image and I can read 15/10.

the same chart printed in black on white lets me read only 10/10 and I
have multiple images at the beginning.

but I am improving day by day.

--
Please visit
http://www.stores.ebay.it/juppiterconsultingrishi
and you can buy a replica of the Original Dr. Bates book
"Perfect Sight Without Glasses"
and if you are interested, join the group
http://health.groups.yahoo.com/group/PerfectSight/