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From: Leo.Bores@p25.f15.n114.z1.fidonet.org (Leo Bores)
Date: (1991)

In a message of <May 27 17:37>, Michael A. Covington (1:114/15) writes:

 MA>There's a widespread folk belief that if children are too bookwormish,
 MA>they will become nearsighted.  I've seen this denied in ophthalmology
 MA>textbooks, and indeed it's hard to think of a mechanism by which such a
 MA>thing might happen, 

Not all textbooks reject this thesis out of hand. I am currently completing a 
medical textbook dealing with the surgery of myopia (an other forms of 
amteropia). I've read just about all (and I do mean ALL) of the extent 
literature (including Soviet). While the "near work hypothesis" is not as 
active as once believed, there is just too much evidence by competent 
observers to ignore it as a factor. The mechanism by which this might occur is 
the rub - the obvious answer is too hard for most physicians to digest. During 
the act of focusing for near (accomodation) a considerable intraocular 
pressure rise can be detected. It can be postulated that that pressure could 
be causing expansion of the relatively underdeveloped posterior segment of the 
enclosing shell of the eye (the sclera). Increase in axial length is a decided 
factor in some types of myopia. The rub lies in the fact that axial 
lengthening is not always present in eyes whose myopia progresses.

What is not in question is that the growth of the eye is a coordinated process 
and not a random event. Most of this adjustment of the optical components of 
the eye occurs between ages 3 and 13 (most babies are born far-sighted). It is 
eveident that it is possible that near work stimulates certain aspects of this 
process and/or supresses others. Since this explanation is somewhat 
teleological - most physicians have a problem with it. The evidence, though, 
is much too strong to dismiss.

 MA>My wife and I were both constant readers as children, we are now quite
 MA>myopic, and we have a daughter who, at 6, is becoming a constant 
 MA>reader.
 MA>Personally, I think I gained more from being hyper-literate than I 
 MA>would
 MA>have gained from good eyesight. But should we do anything specific to
 MA>increase our daughter's chances of continued good vision (presently
 MA>excellent)?

The question of intelligence and myopia is an interesting one (as is the 
personality profile). The fact is that the degree of intelligence evinced my 
myopes as opposed to hyperopes and emmetropes really depends on how the test 
was conducted. If the IQ test is based on reading skills, then the myope will 
consistently show a higher score. If based on other criteria - there is no 
statistically significent difference in the groups. As a matter of fact, both 
my children score near genius level (don't know where they got that B-T-W) - 
one is far-sighted and the other is emmetropic (has normal vision). The answer 
is that myopia tends to be inherited and since the parents are usually better 
educated (through enhanced reading skills) the child is also likely to do well 
even if not myopic due to parental influence - a BIG factor.

I would advise that you do nothing to interfere with her reading. If she shows 
a significent increase in her myopia (1 diopter/year) then MAYBE the use of a 
cycloplegic drop to supress accomodation could be administered. I'm against 
such use, B-T-W. Odds are that she will progress (but not badly) and that she 
will maintain excellant correctable vision.

Leo Bores, M.D.

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