Recent trend of increasing myopia can be traced to infancy

The Relationship between Selected Parameters and the Occurrence of Premyopia in a Group of 1155 Children Aged 8 in Northwestern Poland

Background: Determination of the number of pupils at risk of developing pre-myopia and selected ophthalmic parameters in a group of 1155 children aged 8. Material: Ophthalmic examinations were performed in Polish 8-year-old, /1518 individuals/; 1155 of whom presented complete data for analysis. There was a total of 554 (47.9%) girls and 602 (52.1%) boys. Examination of the anterior and posterior segment of the eye, evaluation of accommodation, convergence, heterophoria, alignment of the eyeball, muscular balance with ocular mobility in 9 directions of gaze, and spatial vision were tested. Refraction was obtained under cycloplegia. Refractions (spherical equivalent, SE). were categorized as pre-myopia (-0.50 D-+0.75 D), myopia (≤-0.5 D), emmetropia (>-0.5 D to ≤+0.5 D), mildly hyperopia (>+0.5 D to ≤+2.0 D) and hyperopia (>+2.0 D). Data analysis was performed using Statistica 13.5 software: chi-squared, Pearson's, t-Student, and U Mann-Whitney tests. p-values of <0.05 were considered statistically significant. Results: Pre-myopia was diagnosed in as many as 704 subjects (60.9%) with a similar frequency among both girls-328 (46.6%)-and boys with 376 (53.4%). Conclusions: Current data indicates that the growing group of myopic individuals in many industrialized countries is the sixth most common cause of blindness. Further research is crucial to understand the factors underlying accommodative and binocular mechanisms for myopia development and progression and to make recommendations for targeted interventions to slow the progression of myopia in a group of early school children.

The Guiding Significance of Ocular Biometry in Evaluating the Refractive Status of Preschool Children

INTRODUCTIONS

This study aimed to analyze the correlation between refractive status and ocular biological parameters in preschool-age children (3-6 years old), establish a regression curve, guide the clinical judgment of children's refractive status, and improve the accuracy of refractive screening for this age group.

METHODS

A total of 508 children, aged 3-6 years, were admitted to the hospital, exhibiting symptoms of ametropia and a need for dilation optometry. Among these, 326 children were included in the statistics group, having been examined between August 2021 and October 2022, and 182 children were included in the validation group, having been examined between November 2022 and March 2023. Using IOL Master700, ocular biometry parameters were measured for all participants, including axial length (AL), keratometry readings (K1 and K2), anterior chamber depth (ACD), lens thickness (LT), and central corneal thickness (CCT). One percent atropine sulfate eye gel was administered, and then the spherical equivalent (SE) was calculated by Bennett's formula. The correlation between SE and other ocular biometrics was analyzed, followed by the establishment of an SE prediction equation. The SE prediction equation was used to calculate the spherical equivalent (SE#) using ocular biometry data from the validation group, and the consistency between SE and SE# was evaluated.

RESULTS

SE showed a negative correlation with AL/CR (r = -0.936), AL (r = -0.811), ACD (r = -0.500), age (r = -0.396), and Km (r = -0.213) (p < 0.001), and positive correlation with LT (r = 0.301), LP (r = 0.176) (p < 0.001). A multiple linear regression equation was established for SE using the stepwise selection method, SE = 49.232 - 23.583 × AL/CR + 1.703 × ACD + 0.589 × Km - 0.609 × LP + 1.103 × LT (R2 = 0.997). Based on the regression equation, the predicted SE# highly correlated with SE after cycloplegia in the validation group (r = 0.998, p < 0.001).

CONCLUSION

The main ocular biological factors of ocular diopter in children aged 3-6 years are AL/CR, ACD, Km, LP, and LT, which are jointly influenced by multiple factors. Ocular biometry is a reliable predictor of real refraction among children aged 3-6.

The Effect of 0.01% Atropine Eye Drops on the Ocular Surface in Children for the Control of Myopia-The Primary Results from a Six-Month Prospective Study

Purpose

To evaluate the effect of 0.01% atropine eye drops on the ocular surface in children for the control of myopia.

Methods

A total of 72 participants were recruited for this prospective study. Prior to and after 1, 3, and 6 months of 0.01% atropine administration, an ocular surface disease index (OSDI) questionnaire was obtained, Keratograph 5M was used for the measurement of the tear meniscus height (TMH), noninvasive keratographic tear film break-up time (NK-BUT, the first keratographic break-up time, [NK-BUT_first] and the average keratographic break-up time, [NK-BUT_ave]), bulbar redness (BR), meiboscore (MS), and anterior segment optical coherence tomography (AS-OCT) was used to calculate the inferior tear meniscus area (TMA).

Results

After using the 0.01% atropine eye drops for 1 month, 9 subjects complained of discomfort immediately after administration, but this quickly subsided, and 1 subject was temporarily dazzled. All the ocular surface symptoms were mild and occurred rarely. After 3 months, these complaints no longer occurred. Compared with the baseline values, the OSDI scores (0.08 ± 0.28), values of TMH (0.23 ± 0.04 mm), TMA (0.0420 ± 0.0444 mm²), NK-BUT_first (9.39 ± 5.25 s), NK-BUT_ave (10.49 ± 4.94 s), BR (0.63 ± 0.37), and MS (0.89 ± 0.70) did not change significantly after 6 months of 0.01% atropine eye drop administration (P > 0.05).

Conclusion

In this 6-month prospective study, no side effects were observed on the ocular surface after using 0.01% atropine in children.

Establishment of correctly focused eyes may not require visual input in arthropods

For proper function, vertebrate and invertebrate visual systems must be able to achieve and maintain emmetropia, a state where distant objects are in focus on the retina. In vertebrates, this is accomplished through a combination of genetic control during early development and homeostatic visual input that fine-tunes the optics of the eye. While emmetropization has long been researched in vertebrates, it is largely unknown how emmetropia is established in arthropods. We used a micro-ophthalmoscope to directly measure how the lens projects images onto the retina in the eyes of small, live arthropods, allowing us to compare the refractive states of light-reared and dark-reared arthropods. First, we measured the image-forming larval eyes of diving beetles (Thermonectus marmoratus), which are known to grow rapidly and dramatically between larval instars. Then, we measured the image-forming principal anterior-median eyes of jumping spiders (Phidippus audax) after emergence from their egg cases. Finally, we measured individual ommatidia in the compound eyes of flesh flies (Sarcophaga bullata) that had developed and emerged under either light or dark conditions. Surprisingly, and in sharp contrast to vertebrates, our data for this diverse set of arthropods suggest that visual input is inconsequential in regard to achieving well-focused eyes. Although it remains unclear whether visual input that is received after the initial development further improves focusing, these results suggest that at least the initial coordination between the lens refractive power and eye size in arthropods may be more strongly predetermined by developmental factors than is typically the case in vertebrates.

Will the long-term use of atropine eye drops in children increase the risk of dry eye?

In recent years, some studies indicates that atropine eye drops is one of the most effective interventions for myopia. Due to large demand, the use of low-concentration atropine eye drops to reduce myopia progression is popular in China. Considering that the underlying mechanism of atropine eye drops in controlling the progression of myopia is still unclear, it is reasonable to pay enough attention to whether the long-term use of atropine eye drops in children will increase the risk of dry eye.