Introduction
Uncorrected refractive errors and especially myopia are the leading
disorders that cause vision loss in the world.1Recently, it has been reported that over 157 million people suffer from
vision loss related to mid or severe refractive disorders
globally.1 The estimated cost of this burden to the
global economy has been reported that to be over US $ 269 billion
annually.2 Accordingly, refractive defects present a
major public health problem in the world.
The most common refractive error type is hypermetropia in the postnatal
term.3 The post-natal hyperopic state regresses over
time due to physiological emmetropization mechanisms associated with
alters in the axial length of the eyeball, lens, and corneal refractive
power. If the emmetropization mechanism fails or delays during this
period due to environmental or hereditary reasons, refractive errors
occur.4-6 Although underlying risk factors and onset
mechanisms are known, the underlying mechanisms of refractive errors is
not fully understood yet.
Epidemiological indicators have shown that there has been a significant
increase in the prevalence of myopia in the last decade. Clinically,
early diagnosis of myopia initial and progression is crucial to control
this refractive error. Eventually, uncorrected myopia may have a risk of
complications related to detachment or neovascularization of the retina,
early cataracts, and glaucoma.7 These complications
not only related to the high socio-economic treatment costs but also may
arise irreversible conditions for patients, such as blindness.
Clinical studies are essential to analyze the refractive errors and
ocular biometric changes of the populations in the onset age ranges of
myopia.8 Such information is also necessary due to
understanding the progressive nature of refractive errors. Rozemaet al. 9 have reported that monitoring the
progression of ocular biometric parameters on school-age children up to
adolescence was an ideal method for interpreting biometric changes
related to the initiation of myopia. However, the above-mentioned
epidemiologic data of 7-12-year-old children are not available for
Turkish population in the literature.
Wolffsohn et al. 10 have reported that potential
myopia calculators could be beneficial tools to reflect the average
potential outcome based on research data. Authors have emphasized that
the data should be collected based on carefully selected cases examined
for between 2 and 5 years only. To the best of our knowledge, no methods
have been prescribed yet to calculate the amount of refractive error
onset in school-age children. Also, it has been reported that such optic
calculators could be employed as a guide to estimate the risk of
developing myopia. Possibly, such optic calculators might be employed as
a guide to estimate the risk of developing myopia.11
With this motivation, the current study aims to correlate the repetitive
measurements, their onset biometric parameters that may indicate
progressions, such as refractive errors. More specifically, we aimed at
evaluating consecutive measurements of the biometric parameters, age,
and refraction error in a Turkish population at primary school age. The
null hypothesis of this cohort study assumes that there was no
correlation or regression amongst the consecutive measurements.