Background:Axial myopia is the most common type of myopia.However,due to the high incidence of myopia in Chinese children,few studies estimating the physiological elongation of the ocular axial length(AL),which does n...Background:Axial myopia is the most common type of myopia.However,due to the high incidence of myopia in Chinese children,few studies estimating the physiological elongation of the ocular axial length(AL),which does not cause myopia progression and differs from the non-physiological elongation of AL,have been conducted.The purpose of our study was to construct a machine learning(ML)-based model for estimating the physiological elongation of AL in a sample of Chinese school-aged myopic children.Methods:In total,1011 myopic children aged 6 to 18 years participated in this study.Cross-sectional datasets were used to optimize the ML algorithms.The input variables included age,sex,central corneal thickness(CCT),spherical equivalent refractive error(SER),mean K reading(K-mean),and white-to-white corneal diameter(WTW).The output variable was AL.A 5-fold cross-validation scheme was used to randomly divide all data into 5 groups,including 4 groups used as training data and one group used as validation data.Six types of ML algorithms were implemented in our models.The best-performing algorithm was applied to predict AL,and estimates of the physiological elongation of AL were obtained as the partial derivatives of AL_(predicted)-age curves based on an unchanged SER value with increasing age.Results:Among the six algorithms,the robust linear regression model was the best model for predicting AL,with a R^(2) value of 0.87 and relatively minimal averaged errors between the predicted AL and true AL.Based on the partial derivatives of the AL_(predicted)-age curves,the estimated physiological AL elongation varied from 0.010 to 0.116 mm/year in male subjects and 0.003 to 0.110 mm/year in female subjects and was influenced by age,SER and K-mean.According to the model,the physiological elongation of AL linearly decreased with increasing age and was negatively correlated with the SER and the K-mean.Conclusions:The physiological elongation of the AL is rarely recorded in clinical data in China.In cases of unavailable clinical dat,an ML algorithm could provide practitioners a reasonable model that can be used to estimate the physiological elongation of AL,which is espedally useful when monitoring myopia progression in orthokeratology lens wearers.展开更多
AIM: To investigate ophthalmologic findings in children with thalassemia major(TM) and compare the findings with healthy controls. ·METHODS: In a cross-sectional study,43 children with thalassemia major from pedi...AIM: To investigate ophthalmologic findings in children with thalassemia major(TM) and compare the findings with healthy controls. ·METHODS: In a cross-sectional study,43 children with thalassemia major from pediatric hematology outpatient clinics from two university hospitals and age/sex matched 47 healthy children were included in the study. After a complete ophthalmic examination,tear function tests including the Schirmer test,fluorescein tear breakup time(BUT),ultrasound pachymetry,and axial length measurement were performed. Obtained data was recorded for statistical analysis and the values of right eyes were compared between groups. ·RESULTS: The mean best corrected visual acuity was 1.34 ±0.75 in TM and 1.08 ±0.28 in controls. It was found lower than 0.1 logMAR unit in 10(23.2%) children with TM and 2(4.2%) in controls,and the difference was statistically significant(P 【0.05). The mean central corneal thickness was 540±26.95 in children with TM and 536.98± 20.45μm in controls(P 】0.05). The mean axial length was 22.53±0.50 in TM and 22.57±0.43mm in the control group. The mean Schirmer test score was 19.94±6.91 in TM and 24.22±3.95mm in the control group(P 【0.01). The mean BUT score was 9.62 ±1.28 in TM and 9.73 ±0.6s in the control group(P 】0.05). ·CONCLUSION: In TM,while corneal thickness,axial length,and BUT are close to controls,the Schirmer scores are less than normal. The study revealed that TM may be affected by the tear function and visual acuity.展开更多
基金This work was funded by the National Natural Science Foundation of China(Grant No.81870684 and 81421004)the HuaXia Translation Medicine Fund For Young Scholars(Grant No.2017-B-001)+2 种基金the Non-Profit Central Research Institute Fund of the Chinese Academy of Medicine Sciences(Grant No.2019HY320001)the National Key Research and Development Program of China(2017YFE0104200)the National Key Instrumentation Development Project of China(2013YQ030651).
文摘Background:Axial myopia is the most common type of myopia.However,due to the high incidence of myopia in Chinese children,few studies estimating the physiological elongation of the ocular axial length(AL),which does not cause myopia progression and differs from the non-physiological elongation of AL,have been conducted.The purpose of our study was to construct a machine learning(ML)-based model for estimating the physiological elongation of AL in a sample of Chinese school-aged myopic children.Methods:In total,1011 myopic children aged 6 to 18 years participated in this study.Cross-sectional datasets were used to optimize the ML algorithms.The input variables included age,sex,central corneal thickness(CCT),spherical equivalent refractive error(SER),mean K reading(K-mean),and white-to-white corneal diameter(WTW).The output variable was AL.A 5-fold cross-validation scheme was used to randomly divide all data into 5 groups,including 4 groups used as training data and one group used as validation data.Six types of ML algorithms were implemented in our models.The best-performing algorithm was applied to predict AL,and estimates of the physiological elongation of AL were obtained as the partial derivatives of AL_(predicted)-age curves based on an unchanged SER value with increasing age.Results:Among the six algorithms,the robust linear regression model was the best model for predicting AL,with a R^(2) value of 0.87 and relatively minimal averaged errors between the predicted AL and true AL.Based on the partial derivatives of the AL_(predicted)-age curves,the estimated physiological AL elongation varied from 0.010 to 0.116 mm/year in male subjects and 0.003 to 0.110 mm/year in female subjects and was influenced by age,SER and K-mean.According to the model,the physiological elongation of AL linearly decreased with increasing age and was negatively correlated with the SER and the K-mean.Conclusions:The physiological elongation of the AL is rarely recorded in clinical data in China.In cases of unavailable clinical dat,an ML algorithm could provide practitioners a reasonable model that can be used to estimate the physiological elongation of AL,which is espedally useful when monitoring myopia progression in orthokeratology lens wearers.
文摘AIM: To investigate ophthalmologic findings in children with thalassemia major(TM) and compare the findings with healthy controls. ·METHODS: In a cross-sectional study,43 children with thalassemia major from pediatric hematology outpatient clinics from two university hospitals and age/sex matched 47 healthy children were included in the study. After a complete ophthalmic examination,tear function tests including the Schirmer test,fluorescein tear breakup time(BUT),ultrasound pachymetry,and axial length measurement were performed. Obtained data was recorded for statistical analysis and the values of right eyes were compared between groups. ·RESULTS: The mean best corrected visual acuity was 1.34 ±0.75 in TM and 1.08 ±0.28 in controls. It was found lower than 0.1 logMAR unit in 10(23.2%) children with TM and 2(4.2%) in controls,and the difference was statistically significant(P 【0.05). The mean central corneal thickness was 540±26.95 in children with TM and 536.98± 20.45μm in controls(P 】0.05). The mean axial length was 22.53±0.50 in TM and 22.57±0.43mm in the control group. The mean Schirmer test score was 19.94±6.91 in TM and 24.22±3.95mm in the control group(P 【0.01). The mean BUT score was 9.62 ±1.28 in TM and 9.73 ±0.6s in the control group(P 】0.05). ·CONCLUSION: In TM,while corneal thickness,axial length,and BUT are close to controls,the Schirmer scores are less than normal. The study revealed that TM may be affected by the tear function and visual acuity.
