In Singapore, the vision of 421,116 males between the ages
of 15 and 25 was examined. In 1974-84, 26.3% were myopic;
in 1987-91, 43.3% were myopic. Both the prevalence and severity
of myopia were substantially higher as the level of education
increased. The prevalence rate was 15.4% in males with no
formal education and increased steadily through the education
levels to reach 65.1% among the university graduates in 1987-91.
This huge sampling conclusively proves that prolonged close
work, including reading and computer usage, is a major cause
of myopia. (M.T. Tay, K.G. Au Eong, C.Y. Ng and M.K. Lim,
"Myopia and Educational Attainment in 421,116 Young Singaporean
Males," Ann. Acad. Med. Singapore, 1992, Nov;21(6):785-91).
This conclusion has been confirmed by recent research reported in the July 10, 2004 edition of New Scientist in an article entitled "Lifestyle causes myopia, not genes." Here is an extract from the article:
Contrary to popular belief, people in east Asia are no more genetically susceptible to short-sightedness than any other population group, according to researchers who have analyzed past studies of the problem.
The epidemics of myopia in countries such as Singapore and Japan are due solely to changes in lifestyle, they say, and similar levels could soon be seen in many western countries as lifestyles there continue to change.
"As kids spend more time indoors, on computers or watching telly, we are going to become just as myopic," says Ian Morgan of the Visual Sciences Group at Australian National University in Canberra.
Myopia is on the increase in most places, but in countries such as Singapore it has reached extraordinary levels. There, 80 per cent of 18-year-old male army recruits are myopic, up from 25 per cent just 30 years ago.
Employers such as the police are having problems finding people who meet their requirements. There is also an increasing incidence of extreme myopia, which can lead to blindness.
There is little doubt about at least one underlying cause. Children now spend much of their time focusing on close objects, such as books and computers. To compensate the eyeball is thought to grow longer. That way less effort is needed to focus up close, but the elongated eye can no longer focus on distant objects.
The argument is about why the rate of myopia is so much higher in east Asia than elsewhere. The conventional view is that people from the region have genetic variations that make them more susceptible. But after reviewing over 40 studies, Morgan and Kathryn Rose of the University of Sydney argue that there is no evidence to support this.
The pair, whose work will be published in Progress in Retinal and Eye Research, use several lines of evidence to debunk the idea that genes can explain the Asian epidemics. For instance, 70 per cent of 18-year-old men of Indian origin living in Singapore have myopia, while in India itself the rate is roughly 10 per cent.
Another study found myopia rates of 80 per cent in 14 to 18-year-old boys studying in schools in Israel that emphasise reading religious texts. The rate for boys in state schools was just 30 per cent.
In another study, researchers at Spain's Complutense University found that 31.3% of first-years were nearsighted. Among those four to six years older, in their final year, the rate was 49%. Research author Dr. Rafaela Garrido, who presented her findings to the 10th International Myopia Conference in Cambridge in July 2004, says: "Some students are spending too long in intensive near work with their eyes. It is also a problem with people who spend too long on a computer or using a microscope. It's difficult to ask students to do less reading, as it is essential to passing courses, but we have to find ways to deal with the stress on the eyes."
2. Close work causes the ciliary
muscle to change the shape of the lens, a process called accommodation.
Proof:
This is common knowledge and is covered in all vision textbooks.
3.
Prolonged accommodation
causes a spasm of the ciliary muscle which triggers an elongation
of the eye, resulting in myopia.
Proof:
This is self-evident. Many nearsighted people have noticed
that their distance vision is worse after a long period of
reading. After a short period of rest, the vision improves
to its former state. This is explained by the tightening of
the ciliary muscle and its inability to relax as soon as the
close work is ended. This illustrates a TEMPORARY spasm of
the ciliary muscle, since normal vision returns quickly.
A temporary spasm will certainly relax after a night’s
sleep. But if too much close work is done, a second stage
of the spasm develops, a CHRONIC spasm. This does NOT relax
after a night’s sleep and its existence is reinforced
by the NEXT day’s close work.
The ciliary muscle is attached to tissues (the sclera) that extend around the rear of the eye. When these tissues are kept in tension constantly because of the chronic ciliary spasm, they begin to stretch. A related pressure increase occurs in the vitreous, or large chamber of the eye. Studies have shown that during accommodation, the pressure inside the eye can increase by as much as 50%. This is a clear indication of the force exerted by the ciliary muscle. In time, the stretched sclera creates a longer eye. The increased volume is filled by fluid produced by the ciliary muscle itself. The vitreous fluid inside the eye thus becomes more watery, and is the main reason why myopic people see "floaters" more often than nonmyopic people.
A highly myopic eye can become as much as 25% longer than
a normal, nonmyopic eye. This has been determined by X-rays
and by examining eyes taken from cadavers. Pictures of such
eyes are published in vision textbooks. Some may claim that
this abnormal elongation is caused by some unknown, inherited
factor in our genes. But this idea has been proven false.
The above-mentioned New Scientist article confirms that "there is little doubt about at least one underlying cause [of myopia]. Children now spend much of their time focusing on close objects, such as books and computers. To compensate, the eyeball is thought to grow longer. That way less effort is needed to focus up close, but the elongated eye can no longer focus on distant objects."
4. If minus (distance) lenses are
prescribed, accommodation increases.
Proof:
It is a known characteristic of minus (concave) lenses that
they cause light rays to diverge. This requires greater accommodative
effort to bring these rays to a focus on the retina.
5. The increased accommodation caused
by minus lenses causes the ciliary muscle spasm to continue.
Proof:
This is self-evident since the ciliary muscle has no opportunity
to relax.
6. Elongation is irreversible.
Proof:
There is no evidence in the vision research literature to
indicate that the stretching of the eye can be reversed.
7. If plus (reading) lenses are prescribed,
accommodation decreases.
Proof:
It is a known characteristic of plus (convex) lenses that
they cause light rays to converge. This helps the lens of
the eye (also convex) to do its work more easily and with
less accommodative effort to bring these rays to a focus on
the retina.
In the above-mentioned New Scientist article, Karla Zadnik of Ohio State University College of Optometry in Columbus, Ohio, says that lenses that eliminate the stress of focusing on near work should help stop myopia from getting any worse. However, she says that studies show that such lenses are of little help. In response, we would point out that Zadnik seems to be unaware of the published Myopter study mentioned below, in which plus lenses were successfully used to reverse myopia in children. And she apparently also does not understand that the reason "studies show the lenses are of little help", as she puts it, is that the studies have been designed to fail, in order to prove that the preventive approach doesn't work.
As an example, in 1984, a study was done at the College of Optometry in Houston, Texas. The "Houston Myopia Control Study" gave children bifocals with a full correction on the upper part and either a 1 diopter or 2 diopter undercorrection on the lower part. When you consider that many children put their noses in a book and use eight or ten diopters of accommodation (focusing power), such a small undercorrection for close work is not going to make much difference. In addition, the children were given no instruction in not holding the book too close, only reading in good light, etc. It is no wonder that the study was inconclusive,
8. Decreased accommodation slows
the rate of myopia progression.
Proof:
In a study entitled "Bifocal Control of Myopia,"
Kenneth H. Oakley and Francis A. Young described how they
used bifocals with plus lenses on children to reduce their
rate of myopia progression to a fraction of what it would
have otherwise been. (American Journal of Optometry and Physiological
Optics, 52, no. 11, November, 1975).
A study in Hong Kong also showed that wearing less than a
full correction will slow the progress of the myopia. Children
selected for the study were between the ages of 9 and 12.
All were nearsighted, with 1.00 to 5.00 D of myopia. The children
were separated into three groups. Each group was given a different
type of eyeglasses to wear for the two-year period of the
study. The first group wore single vision distance lenses
with a full correction; the second group wore progressive
lenses with a +1.50 add; the third group wore progressive
lenses with a +2.00 add. All children were examined at 6-month
intervals to check the progression of their myopia. Sixty-eight
children completed the study. As expected, more undercorrection
meant slower myopia progression (Leung JT, Brown B. Progression
of myopia in Hong Kong Chinese schoolchildren is slowed by
wearing progressive lenses. Optom Vis Sci 1999; 76:346, 354.
Published 10/07/00).
Single vision lenses: 1.23 D increase
Progressive lenses with +1.50 add: 0.76 D increase
Progressive lenses with +2.00 add: 0.66 D increase
Since it is clear that both prolonged accommodation and the
use of minus lenses induce a ciliary muscle spasm, it follows
that by avoiding these conditions through the use of a plus
lens, the spasm will not occur.
9. The use of a strong plus
lens (reading glasses) that COMPLETELY eliminates accommodation
during prolonged close work not only prevents elongation and
the resulting myopia, but can bring about an IMPROVEMENT in
the vision by relaxing the spasm.
Proof:
The first documented, successful use of plus lenses in this
manner was done by Donald S. Rehm, working with Sidney Heller,
a Pittsburgh, Pennsylvania optometrist in 1974. Children between
the ages of 5 and 14 were used and all experienced an improvement
in their vision. Improvements of up to ONE DIOPTER were noted.
(Donald S. Rehm, “Some Case Histories,” The Myopia
Myth – The Truth about Nearsightedness And How to Prevent
It, pages 101-106, Published 1981 by the International Myopia
Prevention Assn.).
The plus lenses were used in a viewer called a Myopter. (Donald
S. Rehm, “The Myopter Viewer: An Instrument for Treating
and Preventing Myopia,” American Journal of Optometry
and Physiological Optics, Volume 52, May, 1975.) This device
enables the elimination of convergence as well as accommodation,
thus providing a reading environment that is closer to true
distance vision than can be obtained with reading glasses
alone. Here are some case histories:
Case 1: Maureen B., female, student. She
was first seen on September 11, 1974 at age nine. Her spectacle
Rx (the eyeglass prescription required to attain 20/20 vision)
was:
Right -0.25
Left -0.50
She wore a Myopter viewer with +2.00 D lenses for all close
work. She was checked every four weeks and at the end of six
months was 20/20. She continued using a bifocal for all close
work and held steady at 20/20. The bifocal was plano for distance
with a +1.25 D add for reading.
Case 2: Penny H., female, student. She was
first seen on July 6, 1974 at age ten. Her spectacle Rx was:
Right -1.00
Left -1.00
She was given a Myopter viewer with +2.00 D lenses for all
close work. Four weeks later, the Myopter lenses were changed
to +2.25 D. On September 8, 1974, the Myopter lenses were
changed to +2.50 D. After using the instrument for another
four months, she reached 20/20. She was then checked once
a month and stayed at 20/20.
Case 3: Luanne A., female, student. She
was first seen on August 27, 1974 at age fourteen. Her spectacle
Rx was:
Right -0.75 -0.25 x 90
Left -0.75
She was given a Myopter viewer with +2.50 D lenses for close
work. On September 21, 1974, an office visit showed no improvement
so the Myopter lenses were changed to +3.00 D. Four weeks
later, her vision had changed to:
Right -0.50
Left -0.25
On February 15, 1975, her vision had reached 20/20. She continued
using a plano bifocal with a +1.25 D add for all close work.
This held her vision at 20/20.
Case 4: James H., male, student. He was
first seen on May 20, 1974 at age eight. His spectacle Rx
was:
Right -1.00 -0.25 x 90
Left -1.00 -0.25 x 90
He was given a Myopter viewer with +2.00 D lenses. Two months
later, his vision had improved to:
Right -0.75 -0.50 x 90
Left -0.50 -0.25 x 90
At this time, the Myopter lenses were changed to +2.50 D.
His vision was checked again on September 28, 1974 and had
improved to:
Right -0.50
Left -0.50
He was checked every six weeks and on March 15, 1975 he reached
20/20. He continued wearing a plano bifocal with a +1.25 D
add for all close work.
The COMET trial conducted by the U.S. National Eye Institute further confirms that plus lenses will reduce the progression of myopia when properly used. The COMET trial is discussed extensively in our Petition filed with the FDA. Click on the FDA Petition link for a copy of the Petition.
10. Myopia has been shown not to
be inherited.
Proof:
Researchers from Washington State University examined the
eyes of children in Barrow, Alaska. They found that fully
60% of the children were nearsighted. But when they examined
the parents and grandparents they found no myopia. The reason
for the difference was that the children were getting the
benefit of compulsory education. Their parents and grandparents
were illiterate. (Francis A. Young et al, "The Transmission
of Refractive Errors within Eskimo Families," American
Journal of Optometry and Archives of the American Academy
of Optometry 46, no. 9, September, 1969).
This is conclusive proof that the inherited myopia theory
is a myth.
Moreover, in the above-mentioned New Scientist article, Dr. Ian Morgan is quoted as stating that even if genes are involved, the massive amount of close work that we do "is swamping out the genetic influence."
