Some of the optometric professional
bodies and organisations, such as the
Association of Optometrists (AOP),
have released statements regarding the
implementation myopia control within
UK practices. The AOP’s statement,
‘Juvenile Myopia Control’ 4 , states that
several evidence-based approaches
have been shown to potentially slow
myopia progression. It goes on to
acknowledge that these areas are within
the competences of an optometrist.
‘The use of dual focus contact lenses
and varifocal spectacles lenses are both
approaches that can be safely practised to
manage myopia. Ortho-k works through a
different mechanism but can also be safely
administered in an optometric practice’,
This online statement and
accompanying evidence supports the
implementation of a strategy for myopia
control within the optometric consulting
room but falls short of suggesting a ‘best
clinical practice’ for myopic children.
The challenge lies in predicting those
at risk of developing high myopia and
then initiating an effective myopia control
strategy. Predictive calculators of myopia
exist in the public domain 5 which can
identify individuals ‘at risk’ of becoming
myopic based on a number of predictive
indices, including the history of parental
myopia, sibling refractive error, ethnicity,
age of onset of myopia and lifestyle
parameters. Implementing a myopia
control strategy with at-risk patients
represents a targeted approach. Possible
effects of myopia and the benefits of
treatment can be discussed before a child
becomes myopic.
As eye care professionals we have
a duty of care to patients to not only
correct their refractive error but also to
prevent ocular pathology. Disseminating
information about myopia and the
benefits of myopia control can come from
the consulting room, practice materials or
practice website. Nowadays, the internet
has become the preferred source of
information for many people and internet
sources such as www.myopiacare.org
offer the patient an individual predictive
index of myopia and inform them of the
associated risks of myopia. Providing
the patient with independent, evidence-
based resources in this way enables them
to be better prepared to consent to an
appropriate strategy for the care of a
myopic child.
Advice on lifestyle and
outdoor time
Strong evidence exists that spending
time outdoors can protect against the
onset of myopia and possibly reduce
the final level of adult myopia 6,7 . It has
been reported that when children spend
sufficient time outdoors (more than
two hours per day), the risk of myopia
is reduced, even when they have two
myopic parents and continue to perform
near work. The total time spent outdoors
appears to be the important factor,
Figure 1 Myopic Degeneration (courtesy of eyerounds.org)
Figure 2 Spending more time outdoors reduces the risk of myopia progression
rather than the nature of the activity
undertaken 6 . Wu et al 7 . reported that
the incidence of new cases of myopia
over one year was approximately
halved, when the time spent outdoors
was increased by an additional 80
minutes per day (8.4% test group versus
17.6% in the control group). The rate
of progression of myopia in the children
who spent additional time outdoors was
also significantly reduced (0.25D versus
0.38D per year). Seasonal differences
in the rates of myopic progression,
which are faster in winter and
slower in summer, support this
hypothesis further 8 .
The ideal of 2 hours of sunlight a
day 9 may not be possible throughout
all seasons, but a pragmatic approach
to increase outdoor activity by as little
as 40 minutes might significantly delay
onset of myopia. It would seem that
simple exposure to sunlight, potentially
involving the production of Vitamin D
impacts on the peripheral retina and
offers some protective mechanism at the
cellular layer 10 .
Correcting myopia with spectacles
It was once thought that under-
c orrecting myopia would slow its
progression. However, many studies
have now shown that under-correction
actually speeds up progression 11 .
It is therefore important to fully correct
Continued overleaf
January 2017 | etCETera
»
13