Help.
Sorry to intrude to your group, but I tried to post a question.
Unfortunate it came back with rec. unknown. Used this address:
sci.med.vision@googlegroups.com
otisbrown@pa.net - 09 Aug 2005 14:11 GMT
Dear CBF,
I don't know where you are posting from, by you might
try the following site:
www.google.com
Then "click" on groups,
then type
sci.med.vision
You can then read the messages and post
a response.
Best,
Otis
(Engineer)
> Help.
> Sorry to intrude to your group, but I tried to post a question.
> Unfortunate it came back with rec. unknown. Used this address:
> sci.med.vision@googlegroups.com
Simon Dean - 09 Aug 2005 15:55 GMT
> Help.
> Sorry to intrude to your group, but I tried to post a question.
> Unfortunate it came back with rec. unknown. Used this address:
> sci.med.vision@googlegroups.com
Perhaps you could explain then how you managed this support request here
then?
cbf - 10 Aug 2005 16:27 GMT
I just replied as I do now, by pushing the "Reply button" and a new
windows came up.
Tried to make a new string.
Dear Mike,
Subject: Response to Mike Tyners insistance that the natural
primate eye is not "dynamic", an therefore there is not,
nor can there ever be proof of of that relationship.
It isn't that they can't see the solution,
It is that they can't see the problem.
G. K. Chesterton
I appreciate the fact that you use a full-strength minus on
your children and grand-children -- and believe that there is no
proven relationship between the average visual-environment and the
refractive state of the natural eye. You state the "majority
opinion" very forcefully -- as I accept your statement as a honest
affirmation of that belief. But equally, even your fellow ODs and
some ophthalmologist do not share your majority-opinion, and are
skeptical of the over-prescription of a minus lens.
They believe that the "near" environment should be
substantially "changed" with a strong plus -- if a negative
refractive state is to be avoided. Their belief is strong enought
and the experimental data convincing enought -- so that they have
their own children (automatically) wearing a strong plus when the
child's refractive state is zero (and vision is 20/20). Thus your
position is understood, and honest, but the goal of prevention, as
the second opinion is equally honest on a "medical" level.
Selecting small-sample (n = 18) is not the way to reach a
conclusion -- given the above facts. You selectively igore
studies that deny the conclusion you have jumped to, and
specifically the Oakley-Young study.
A best, we must agree that these results are profoundly
contradictory, and a healthy respect for true-prevention with the
plus should continue to be developed.
Calling EITHER the majority-opinion OR the second-opinion
"bull s___" simply does not "work".
Let us show more respect for BOTH these honest opinions and
why they must continue to exist -- side by side.
Best,
Otis
+++++++++++++++++++++++++++++++++++
From: "Mike Tyner"
Otis> This is a typical and tragic response to "Bates" and ANYONE
who objects to the over-prescription of a minus lens -- and
its consequences. This is why people in medicine respect
the development of a "preventive" second-opinion.
MikeOD> Perhaps you could explain why Dr. Goss's subjects wore
excess minus but didn't get nearsighted faster.
Goss> Thirty-six subjects (18 males and 18 females) ranging in
ages from ...]
[Comment: A very small "sample size" leads to very poor
conclusions. Drawing a "long" conclusion, that a minus lens
has NO effect on the refractive state of the natural eye --
simply is not accurate, nor good science. Francis Young
used a sample size of over 200. I suggest that Goss's study
is meaningless for that reason. Yet another "political"
study. OSB]
MikeOD> Perhaps you won't. Perhaps there is no room in your
philosophy for what happens in humans wearing glasses.
[Comment: In fact there is the great concern about the "secondary
effect" of a minus lens on the refractive state of the
natural eye -- based on the conclusions about the natural
primate (monkey) eye behavior. But you in your "wisdom"
insist that all objective, scientific data concerning the
proven behavior of the natural primate eye be EXCLUDED
before the person begins reviewing this data himself. I
suggest that the person who wishes to work on
true-prevention take in to account this data that you
exclude -- on your "authority". OSB]
MikeOD> Perhaps they lied. Perhaps the kids had a spare pair of
glasses at home and they switched glasses without telling
anyone.
[Comment: The small sample size is the reason for the failure to
get accurate results -- not the kids actions. OSB]
MikeOD> Perhaps you could point to SOME published article that
actually measured human myopia and found it got worse in
those wearing glasses.
[Comment: The Oakley-Young Pullman study showed that a "high
segment" and strong plus had the effect of stopping the
eye's negative movement, i.e., the "down" rate for the plus
group was approximately zero diopters, while the
single-minus went "down" at a rate of -1/2 diopter per year.
Since you dispute this result, let us call this the "second
opinion", that the natural (primate) eye behaves as a
dynamic system. To see this effect more completely, and
prove this "dynamic" characteristic of the natural eye is it
necessary to perform "input" versus "output" testing on the
natural primate eye, where the input (in diopters) is
changed in a negative direction, and the "output" (in
diopters) is measured accurately -- for the refractive
states of all the eyes under test. OSB]
MikeOD> Perhaps you can't.
[Comment: I already did. OSB]
MikeOD> In which case you're preaching myth in a science
newsgroup. You are welcome to take your pleasant
discussions to alt.med.vision.improve.
[Comment: If fact I have outlined a scientific test to verify
that the natural eye is a sophisticated system, and behaves
as we should expect such a system to behave. It is true
that this is pure science, and not "medicine" as you like to
say. But denying objective scientifc facts for the
convenience of "quick-fixing" the public is hardly science,
or a scientific approach to understanding the proven
behavior of the natural eye. The real task is to help the
person understand these issues and apply to concept
correctly to keep his distant vision clear for life --
assuming he has that goal and interest. OSB]
Best, Otis
-MT
********************************
BIFOCAL CONTROL OF MYOPIA
Authors:
Kenneth H. Oakley, MD.
Bend, Oregon
and
Francis A. Young, Ph.D.
Primate Research Center
Washington State University
Pullman, Washington
ABSTRACT
Forty-three Native American bifocal wearers grouped by yearly
age levels from 9 to 15 with a mixed group of 6 to 8 year olds are
matched on beginning age, sex, beginning refractive error and
ending age with 104 Native American control subjects.
Similarly, 226 Caucasian bifocal wearers are matched on the
same criteria against 382 control subjects. Although the
comparisons are made on each age group, the average annual rate of
progression for the bifocal Native American subjects is -0.12 and
-0.10 diopters in the right and left eyes respectively against a
comparable rate of progression of -0.38 and -0.36 diopters for the
control subjects
These differences are significant but not as significant as
those found on the Caucasian subjects of -0.02 and -0.03 diopters
right and left eyes against -0.53 and -0.52 diopters for the
controls. The meaning of these differences is discussed.
++++++++++++++++++++++++++++++++++
[Comment: A difference in refractive state between the
single-minus and the plus group, for 226 "test" versus 382
"control" is HIGHLY SIGNIFICANT. These numbers far exceed the the
n = 18 of the Goss review. OSB]
STUDY TEXT
Recently a number of investigators have reported successful
control of the progression of myopia in children through the use
of 1% atropine sulfate drops on a daily or alternate day basis.
(Gostin, 1962; Bedrossian, 1966; Boyd, 1969; Dyer and Thel, Jr.,
1970.) The success of the use of atropine for the control of
myopia is believed to be related to the reduction of the
accommodative response under the cycloplegic action of atropine.
Young (1965) reported similar results on monkeys.
If the reduction of the accommodative response is related to
the progression of myopia, it seems reasonable that the reduction
of the accommodative response through the use of plus reading
glasses or through the use of bifocals on already myopic children
should also have the effect of reducing the rate of progression of
myopia in children. Such has been reported by a number of
investigators (Betz, 1949; Gamble, 1949; Miles, 1957, 1962;
Parker, 1958; and Warren, 1955.)
Mandell (1959) found no evidence to support the concept of
control of myopia progression through the use of bifocals.
Mandell indicated that what is needed to establish the merits of
bifocal control is a study in which bifocals are fitted to one of
two groups of myopic patients comparable in age, degree of myopia,
rate of progression before correction and environment. Under
these conditions the rate of progression of the group given
bifocals could then be easily checked against the rate of the
control group. He further points out that a study of this type
presents difficult operational procedures due to the problem of
obtaining suitable subjects for the necessary length of time.
Since Mandell was not able to carry out such a study he
substituted an evaluation of patients in the clinical records of a
practicing optometrist and proceeded to violate his own suggested
criteria.
Thus the patients who were fitted with bifocals had an
average initial refractive error of 2.75 diopters with an average
initial age of 14.3 years, while his control patients had an
average initial refractive error of 1.48 diopters with an average
initial age of 17.1 years.
Clearly, the subjects who were fitted with bifocals were
progressing at a higher rate since they had developed almost twice
as much myopia by age 14 than the control subjects had by age 17.
Also, since myopia is supposed to more or less stop progressing in
the late teens (at the end of high school for individuals who do
not go beyond high school) one could expect the 17 year old
subjects to show less progression with or without bifocals than
the younger subjects who were wearing bifocals.
This lack of matching between the bifocal wearers and the
controls make it difficult to draw conclusions, although Mandell
does conclude that the wearing of bifocals had little or no effect
on the progression of myopia.
The present study represents an attempt on the part of the
authors to achieve the suggestions made by Mandell in designing a
study to determine the effect of bifocals on the progression of
myopia and to compare these subjects with control subjects who
demonstrate a similar age and initial refraction and who have been
followed for a number of years.
One of the difficulties of carrying on a longitudinal study
which requires cooperation over time on the part of the subjects
involved in the study is to achieve such cooperation consistently.
This is particularly important in attempting to evaluate the
effect of such drugs as atropine or devices as bifocals on the
progression of myopia in children.
If the drug is not used properly or at all, or if the bifocal
is not fit properly or used, the investigator usually assumes that
his instructions have been followed.
However, without adequate checkups, he may be mislead by his
subjects. In an attempt to evaluate this possibility, the present
study utilized two groups for the investigation: one group of
Caucasian children and the other of Native American children.
Continued contact with the two groups of children clearly
indicates that the Caucasian children were much more compulsive in
wearing and using their bifocals than were the Native American
children. Since there was a consistent difference in the two
groups, one might expect a greater effect among the Caucasian
children than among the Native American children.
Subjects
There were two groups of children available as subjects. The
Native American population consisted of 156 children ranging in
age from 6 to 21 with 54 children in the bifocal population and
102 in the control population.
The Caucasian population consisted of 441 subjects who are
divided into 226 bifocal subjects and 215 control subjects with
the same age range as the Native American subjects.
In the Native American population 16 (29.6%) of the bifocal
children were males and 38 (70.4%) were females while 36 (35.3%)
of the control children were males and 66 (64.7%) were females. A
Chi-square test of the sex distribution between the two groups
indicates that there is no significant difference (Chi2 = 0.29
with 1 degree of freedom).
Correspondingly, in the Caucasian population 118 (50.2%) of
the bifocal children were males and 117 (49.8%) were females while
99 (41.6%) of the controls were males and 139 (58.4%) were
females. A Chi-square test of the sex distribution between the
bifocal and control groups for the Caucasian population yields a
value of 3.20 with 1 degree of freedom, which is not significant.
The subjects in all populations were grouped by ages using
the age at which the bifocal subjects began to wear bifocals as
the "beginning age" with the control subjects matched to these
ages. There were sufficient subjects at all age levels between 9
and 15 inclusive in the Native American and Caucasian populations
to form yearly groups as well as a Caucasian group with beginning
age 16.
< snip of the remainder >
*********************************
Am J Optom Physiol Opt. 1984 Feb;61(2):85-93. Related
Articles, Links
Overcorrection as a means of slowing myopic progression.
Goss DA.
Thirty-six subjects (18 males and 18 females) ranging in ages
from 7.38 to 15.82 years received an overcorrection of 0.75 D over
the power required to correct their myopia exactly.
< Major Snip -- The "Goss" sample size is to small to reach a
meaningful conclusion -- see Francis Young's study of over 215
persons in the test-group for a comparison. OSB >
Mike Tyner - 09 Aug 2005 19:54 GMT
> Subject: Response to Mike Tyners insistance that the natural
> primate eye is not "dynamic", an therefore there is not,
> nor can there ever be proof of of that relationship.
See, you totally missed what I wrote. You don't read.
I asked you to find us a doctor who does NOT believe such a relationship
exists. We ALL believe it. We just don't believe YOU.
You never did explain why Goss's subjects got no more nearsighted than their
matched controls. You seem to be pretending it didn't happen. You can't
ignore the human studies, ostrich.
Please tell us where you find that wearing glasses causes human myopia to
worsen.
Please tell us where you find plus lenses have been effective at controlling
myopia.
Or please move your pleasant discussion to alt.med.vision.improve.
-MT
Mike Tyner - 09 Aug 2005 20:22 GMT
> Selecting small-sample (n = 18) is not the way to reach a
> conclusion -- given the above facts. You selectively igore
> studies that deny the conclusion you have jumped to, and
> specifically the Oakley-Young study.
The n was 36. Why didn't they get more nearsighted than the controls? As you
tell us, excess minus ALWAYS cause myopia to increase faster.
> A best, we must agree that these results are profoundly
> contradictory
And since all the other human literature contradicts Dr. Young, we must
agree that plus treatment is not practically useful.
> Calling EITHER the majority-opinion OR the second-opinion
> "bull s___" simply does not "work".
"Not practically useful" is a polite euphemism for "not approved as safe or
effective." Is Donald Rehm making any progress with the FDA? Let us know,
won't you?
> [Comment: A very small "sample size" leads to very poor
> conclusions. Drawing a "long" conclusion, that a minus lens
> has NO effect on the refractive state of the natural eye --
> simply is not accurate, nor good science.
Yeah. It didn't happen, so let's don't draw any conclusions.
> Francis Young
> used a sample size of over 200. I suggest that Goss's study
> is meaningless for that reason. Yet another "political"
> study. OSB]
Too bad you think so. Let's ignore several thousand optometrists who gave up
on Young's technique because it didn't work. Let's ignore several thousand
ophthalmologists who never found it useful or effective, except as platform
for turf wars. Optometrists did it. Optometrists quit doing it. Why?
> [Comment: In fact there is the great concern about the "secondary
> effect" of a minus lens on the refractive state of the
> natural eye
The "great concern" is mostly yours. We'll leave it up to the FDA.
> [Comment: The small sample size is the reason for the failure to
> get accurate results -- not the kids actions. OSB]
But they didn't get more nearsighted than their matched controls. You said
it ALWAYS happens that way. Here it didn't. Why not?
> [Comment: The Oakley-Young Pullman study showed that a "high
> segment" and strong plus had the effect of stopping the
> eye's negative movement, i.e., the "down" rate for the plus
> group was approximately zero diopters, while the
> single-minus went "down" at a rate of -1/2 diopter per year.
So why doesn't it work when others try it?
> MikeOD> In which case you're preaching myth in a science
> newsgroup. You are welcome to take your pleasant
[quoted text clipped - 3 lines]
> that the natural eye is a sophisticated system, and behaves
> as we should expect such a system to behave.
So how come it doesn't work?
-MT