Question:
Today I met with a retired visual training optometrist, a kind of lone
wolf out here at Indiana University. He assured me that patching one eye
and reading (with the aid -- or hindrance, if you want to put it that
way -- of plus-lenses to make things as if they were further away) at the
blur point were excellent ways to reverse myopia. He said that his father
had a practice where he reguarly helped myopic men pass the navy
vision test. Eye improvement through exercise for this man and his father
was not a hypothesis, but an undeniable clinical fact. I won't repeat
here the details of the argument that myopia comes from too much close
work, which he explained to me, but there were a few facts that he
brought to my attention:
1) the development of myopia as a result of too much near work goes along
with/is caused by/leads to (in a vicious circle kind of way) improper
convergence. In particular, myopic eyes tend to over-converge. Thus
getting the eyes to converge properly is important in overcoming myopia.
This is why wearing a patch helps. It removes the strain caused by
improperly converging eyes, strain which leads to refractive error.
2) behind the retina lies a mass of erectile tissue. When blood flows
into your eyes, the erectile tissue pushes the back of the eye forward.
Therefore improved circulation in the eyes can reduce myopia.
This second claim was news to me. Erectile tissue in the retina?! Anyone
heard of this one? Of course it is well reported that acuity improves
during and after aerobic sports, but I had never heard this as an
explanation.
Answer:
2) behind the retina lies a mass of erectile tissue. When blood flows
: into your eyes, the erectile tissue pushes the back of the eye forward.
: Therefore improved circulation in the eyes can reduce myopia.
: This second claim was news to me. Erectile tissue in the retina?! Anyone
: heard of this one? Of course it is well reported that acuity improves
: during and after aerobic sports, but I had never heard this as an
: explanation.
This should be an easy one.
To correct 3 diopters of myopia requires moving the retina forward 1mm,
which is a considerable distance in the eye.
There is no "erectile" tissue in or around the retina. The choroid, the
vascular channel that lies under the retina, may become thickened in some
infiltrative diseases such as lymphoma but choroidal blood flow is
auto-regulated and exercise will not increase the thickness of the
choroid to any appreciable amount.
Most offices have the equipment to prove or disprove this hypothesis: an
auto-refractor for objective refractions, and A- or B-scan ultrasound to
measure the distance to the retina before and after exercise. Mt office
is in Manhattan, if anyone cares to put this to the test.