Our office is pleased to offer CRT (Corneal Refractive Therapy)
lenses as mentioned in the followoing article from the UK's Daily Mail. (10/20
Hodgekiss). After fitting the lenses myself for the last 5 years, it has been
my experience that there is very little increase in a child's prescription. It
is most encouraging to be able to fit children with a contact lens that will
halt or slow the progression of myopia!
Contact lenses worn at
night could slow down or even halt sight deterioration in children.The vast majority of children with sight problems are short-sighted — they have
difficulty seeing things far away. This is caused by a misshapen eyeball.
The new contact lenses
work in a similar way to a dental brace, gently pressing on the eye to restore
it to the shape of someone with normal vision.
New research has found
that after a year of use, children had far less sight deterioration than those
who’d worn regular contact lenses.
In normal sight, the
light rays pass into the eye through the cornea. They then hit the retina at
the back of the eye where they are transformed into image-forming signals,
which are then sent to the brain.
With short-sight, the
cornea is either too curved or the eyeball too long. This means the light rays
from distant objects focus in front of the retina, rather than directly on it,
making the objects appear fuzzy.
The overnight lenses,
which have been available for several years to help adults, work by gently
pressing on the cornea, reducing its curvature and thereby refocusing the light
directly on to the retina. It also, in effect, shortens the eyeball.
The reshaping in
adults is temporary because the cornea will gradually spring back to its
original shape, so the lenses must be worn every night. (The lenses themselves
are slightly harder than the softer lenses people commonly use for daytime
wear.)
However, a few years
ago scientists noticed that children who wore this type of contact lens had a
slower deterioration of their eyesight, — the reshaping seemed to be more
permanent.On this observation, a controlled clinical trial of the lenses was set up in
the U.S. two years ago. Around 300 children aged eight to 14 are taking part in
the five-year study, known as SMART.Half of the subjects have been given the overnight lenses, while the others are
using normal contact lenses every day. At the end of the first year, both
groups stopped wearing their lenses for one month to see if their prescription
had changed.
Sight loss is measured
in diopters. In children who are short-sighted it is estimated that sight
deteriorates by 0.25 to 1.2 diopters a year (as a guide, most adults have a
prescription that is no worse than minus 5).
The results showed
that, after the first year, the children in the overnight lens group had no
prescription change; in the control group the average increase was 0.4
diopters.Because shortsightedness is usually picked up by the early teenage years, it is
hoped overnight lenses could at least prevent further sight deterioration.
The reason why
children seem to benefit more than adults is because their eyes are still
growing — this makes it easier to change their shape, just as it’s easier to
fix misaligned teeth in children rather than adults.
Michael Ward, a
13-year- old from Watford, has been wearing the overnight lenses for two years.Before then, the keen sportsman had to either wear his glasses when playing
sport or not wear them at all.
‘It’s made a huge difference
because I can see everything now,’ he says. The rate of his sight deterioration
has also slowed. ‘I went river rafting one weekend and didn’t wear them for two
nights — my sight only started to get worse on the third day.’
Parwez Hossain, a
consultant in ophthalmology at Southampton General Hospital and member of the
scientific committee of the Royal College of Ophthalmologists, says these
lenses could potentially be a cure for short-sightedness, although ‘we won’t
know this for another few years’.