Challenging the Helmholtz Theory
Otis
CHALLENGING THE HELMHOLTZ THEORY
It is about time someone protests against the praise, honor, and glory
given Helmholtz, on his theory of accommodation of the human eye.
As Tscherning violently disagreed with the Helmholtz theory then, I
violently disagree with it now. I challenge all who believe the
Helmholtz theory of accommodation to give some thought as to whether
or not it is even reasonable to believe.
It is not that another theory of accommodation would change eye work
as it is being done today, but it could lead to a new understanding of
refractive and muscular eye troubles, and might improve the eye work
of today and tomorrow. It did this for me over the last forty years.
The crystalline lens of the human eye has little or no elasticity in
the first place. Therefore, it could not be the media of accommodation
in the second place. Certainly it does not have enough elasticity to
focus the human eye, instantaneously, as fast as I can accommodate my
own eyes from far to near and near to far. Yet we know that the human
eye does have the ability to accommodate instantaneously, for any and
all distances.
Then the question arises - if the crystalline lens is not the media of
accommodation, what is it there for, and what is the media of
accommodation???
The crystalline lens is the core of the eyeball, suspended taut in
place in its capsule by the suspensory ligaments, which in turn are
connected to the circular ciliary muscles of accommodation. Instead of
the crystalline lens becoming more or less convex, as per Helmholtz,
under accommodation, it becomes held more or less taut in place, under
accommodation.
Under the Helmholtz theory, the crystalline lens would be held less
taut in place, and of its own weight it would sag or tip, instead of
becoming more or less convex. Its curved surfaces, having a power of
16 to 19 diopters, are more or less neutralized by the curvature of
the humors, making the power of the crystalline nil and useless as a
refracting media. As a refracting media, eyes could do without the
crystalline lens, if internal tone and pressure were not lost in its
removal. Suspended taut in its place, it serves as a solid to steady
the action of the circular ciliary muscle, and to help keep the
eyeball round.
In the act of accommodation, as I see it, the circular ciliary muscle
acts in "shoelace" fashion, contracting in itself, drawing the
crystalline lens taut and at the same time, making the cornea more or
less convex, thereby making the cornea the media of accommodation,
instead of the crystalline lens. It has to be that way; it cannot be
any other way. At least that way is more believable than the old
Helmholtz theory of accommodation. But there is more to say about the
cornea, and its power and action under accommodation.
The cornea has more than enough power to do all the focusing for a
normal human eye. It is so powerful that it bends all rays, incident
on the cornea, directly through even a pinpoint pupil, straight on
through the aqueous humor, the crystalline lens and the vitreous humor
to the retina. It must be remembered and kept in mind that the point
of reversal takes place in the pupil.
Considering a pinpoint pupil, the anterior surface area of the
crystalline lens is so small and neutralized by the aqueous humor,
that it could have little or nothing to do with refraction. That alone
cuts the power of the crystalline lens in half. Then also, the
incident and emergent rays pass through the curvatures of the
crystalline lens at an almost perfect right angle to its curvatures,
on their way to the retina, without being refracted by the crystalline
lens, and just as if the crystalline lens was not there.
In the act of accommodation, the cornea becomes more or less convex by
the action of the ciliary muscle. The act is so minute that it is not
detectable, even with the ophthalmometer. It should be realized that
the eye being examined, while looking into the aperture of the
ophthalmometer, is under accommodation for the distance it is looking.
This gives the corneal curvature under accommodation at that distance.
If it were possible to take the corneal curvature with the
ophthalmometer while the eye was looking at infinity, it might show
less corneal curvature, depending on the type of eye being examined.
While there may not be very much difference, this could prove that the
cornea is the media of accommodation. I can accommodate either one of
my eyes at will. My vision blurs, and I can actually feel the action
of the ciliary muscle making the cornea more convex. I can accommodate
so strenuously that the object I look at shakes, meaning that my
eyeball quivers, but only in the horizontal, as in nystagmus. If I
force my accommodation with both eyes together, my vision blurs up to
a certain point; then my eyes turn inward, and I see blurred and
double. If I then ease up a little in my over-accommodating at will, I
still see blurred, but single. If I ease up all the way, I see clear
and single.
In my over-accommodating at will, with one eye or both, I am actually
making my eyes nearsighted. This means that with my naked eyes, I
would see blurred. If I placed a minus lens before my eyes, I would
see clear. Doing this under the Helmholtz theory of accommodation, I
would be forcing my crystalline lens to bulge into becoming more
convex by its own supposed elasticity. If I believed in the old
Helmholtz theory of accommodation, I would not dare do that with my
own eyes. Not believing in it, and believing in the cornea as the
media of accommodation, I do not fear doing it, and overdoing it, if I
please, as a matter of experimenting with my own eyes. Since the
crystalline lens has little or no elasticity, some other media has to
have a lot of elasticity to perform the instantaneous act of
accommodating. That other media can only be the cornea. No other media
could have such flexibility and elasticity.
Under the old Helmholtz theory, a farsighted eye would mean a lack of
convexity of the crystalline lens, and a nearsighted eye would mean an
over-convexity of the crystalline lens. This is not even reasonable to
believe, but we know it has to be something. If the cornea was the
media of accommodation, a farsighted eye would lack convexity of the
cornea, and a nearsighted eye would mean an over-convexity of the
cornea. That is more reasonable to believe. On close observation of
the corneas, one will find that farsighted eyes have a shallow cornea
and anterior chamber, while nearsighted eyes have an over-convex
cornea and more anterior chamber, with usually large pupils, a glassy
and starry-eyed look, and a bulgy eyed appearance.
Under the Helmholtz theory, presbyopia is supposed to be the
physiological hardening of the crystalline lens. Since the crystalline
lens has little or no elasticity, this theory of presbyopia also is
not even reasonably believable. With the cornea being the media of
accommodation, presbyopia has to be the loss of power or action of the
ciliary muscles, or loss of flexibility of the cornea, or both. It
seems that it has to be a loss of power of the ciliary muscles. It is
not reasonable to believe that the cornea could have such a fault, or
have anything to do with it.
Going beyond what is or is not the theory of accommodation, the
crystalline lens and ciliary muscles have another duty to perform.
They not only serve to help keep the eyeball round, but all extrinsic
muscles oppose each other through it. Without them, the extrinsic
muscles could pull the eyeball out of round. The crystalline lens and
ciliary muscles could perform such duty better with the cornea being
the theory and media of accommodation, than with the old Helmholtz
theory.
Any theory of accommodation would be hard to describe. If one would
imagine the crystalline lens as a solid suspended in place, the
ciliary muscles as a muscular ring, and the extrinsic muscles attached
to it under tension, one would have a better picture of the cornea as
being the media of accommodation.
One has to have a strong imagination to picture the act of
accommodation under the old Helmholtz theory. One may not be able to
catch the cornea becoming more or less convex in the act of
accommodation, but that does not mean that anyone has ever caught the
crystalline lens becoming more or less convex, in the same act. What
proof is advanced, in an attempt to prove the crystalline lens as the
media of accommodation, could be credited to the act of the cornea. In
fact, as stated previously, the act of accommodation in the human eyes
is so minute as to be beyond detection, whether the media be the
cornea or the crystalline lens. However, in either case it takes the
action of the ciliary muscles, which in normal eyes should be as
active as the hairspring of a watch, to activate accommodation.
Whatever the media of accommodation, it has to be fast and
instantaneous. In any case, as I see it, it can only be the cornea.
With the theory of the cornea being the media of accommodation in
mind, I was able to go even farther into the cause and condition of
all refractive and muscular eye troubles, especially in cases of
children and young people, and do something about it. This I could not
have done under the old Helmholtz theory. If others would do as I did
and do some thinking, they might run into the same thing. If they did,
they would find it as revolutionary as I did.
Right now I only wish to establish a change in the theory of
accommodation, from that of Helmholtz to what it should have been all
these years. Once and for all, I would like to see the old Helmholtz
theory of accommodation thrown overboard, and establish the cornea as
the media of accommodation of the human eye. In doing that I would
discredit Helmholtz, as he should have been discredited years ago for
holding back advancement in thinking, in eyework, for all these
years.
Dr. Joseph J. Kennebeck
Neil Brooks
dishonest about this subject.
From: http://www.chinamyopia.org/Preventionmagazine1973.htm
"When Otis S. Brown was a young boy, he dreamed of someday
becoming an airline pilot. In fact, everything he did throughout
those early days in grade school was aimed at achieving that goal.
Then, disaster struck, and Otis Brown's dreams of becoming a
pilot faded as he was fitted with increasingly stronger minus
glasses to correct a worsening case of myopia, or nearsightedness,
a condition which causes distant objects to appear blurred."
I'm sorry your dreams were shattered, O