Myopia is an important public health issue.Great attention has been paid to myopia in children and teenager since its incidence is progressing rapidly worldwide, especially in Asia.Although there are substantial reports on both myopia progression and its risk factors in children and teenager, challenges are encountered when attempting to compare results among individual studies due to different population, definition of myopia, cycloplegic eye drops, refraction methods, and so on.This review aimed to summarize the reports on myopia progression and its risk factors such as age, gender, refractive state, near work, outdoor activities, parental myopia, or parental bearing age in children and teenager (＜18 years) since 1990.

BACKGROUNDThe evaluation of retinal image quality in cataract eyes has gained importance and the clinical modulation transfer functions (MTF) can obtained by aberrometer and double pass (DP) system. This study aimed to compare MTF derived from a ray tracing aberrometer and a DP system in early cataractous and normal eyes.

METHODSThere were 128 subjects with 61 control eyes and 67 eyes with early cataract defined according to the Lens Opacities Classification System III. A laser ray-tracing wavefront aberrometer (iTrace) and a double pass (DP) system (OQAS) assessed ocular MTF for 6.0 mm pupil diameters following dilation. Areas under the MTF (AUMTF) and their correlations were analyzed. Stepwise multiple regression analysis assessed factors affecting the differences between iTrace- and OQAS-derived AUMTF for the early cataract group.

RESULTSFor both early cataract and control groups, iTrace-derived MTFs were higher than OQAS-derived MTFs across a range of spatial frequencies (P < 0.01). No significant difference between the two groups occurred for iTrace-derived AUMTF, but the early cataract group had significantly smaller OQAS-derived AUMTF than did the control group (P < 0.01). AUMTF determined from both the techniques demonstrated significant correlations with nuclear opacities, higher-order aberrations (HOAs), visual acuity, and contrast sensitivity functions, while the OQAS-derived AUMTF also demonstrated significant correlations with age and cortical opacity grade. The factors significantly affecting the difference between iTrace and OQAS AUMTF were root-mean-squared HOAs (standardized beta coefficient = -0.63, P < 0.01) and age (standardized beta coefficient = 0.26, P < 0.01).

CONCLUSIONSMTFs determined from a iTrace and a DP system (OQAS) differ significantly in early cataractous and normal subjects. Correlations with visual performance were higher for the DP system. OQAS-derived MTF may be useful as an indicator of visual performance in early cataract eyes.

Aberrometry ; methods ; Adult ; Aged ; Cataract ; physiopathology ; Female ; Humans ; Male ; Middle Aged ; Visual Acuity ; physiology