Characteristics of hydrogel microspheres in bone tissue engineering / 中国组织工程研究

BACKGROUND:Hydrogel microparticles,due to their porous and injectable properties,have demonstrated unique advantages in biomedical fields,such as the delivery of cells and bioactive factors/drugs,the construction of tissue repair scaffolds.They have broad application prospects. OBJECTIVE:To review the latest research progress and discuss the key problems and challenges in the research of bone tissue engineering based on hydrogel microparticles. METHODS:The relevant articles in PubMed and CNKI were searched by computer.The English key words were"hydrogels,microparticles,microspheres,microcarriers,bone,bone defect,bone repair,bone healing,bone tissue engineering"while the Chinese key words were"hydrogels,microparticles,microspheres,bone tissue engineering,bone defect,bone repair,bone regeneration".The retrieval period was from 2002 to 2022,and 127 articles were finally included for review. RESULTS AND CONCLUSION:(1)At present,various hydrogel microparticles have been developed for use in bone tissue engineering strategies,for example,hydrogel microparticles carrying cells or bioactive factors/drugs,hydrogel microparticles as biological scaffolds,stimulus-responsive hydrogel microparticles,biomineralized hydrogel microparticles,hydrogel microparticles combined with other biological materials.(2)Bone tissue engineering repair strategies based on hydrogel microparticles mainly regulate bone repair by promoting stem cell recruitment and osteogenic differentiation,regulating the local inflammatory microenvironment and promoting angiogenesis at the site of injury.However,the present studies did not deeply explore the effect of bone tissue engineering based on hydrogel microparticles on the recruitment and differentiation of endogenous stem cells and the regulation of the inflammatory microenvironment by the physical and chemical properties of hydrogel microparticles.The long-term in vivo adverse reactions of hydrogel microparticles have not been explored yet,and it is difficult to mass-produce them,thus future research needs to strengthen the mechanism exploration and technical route,so as to provide a reasonable reference for the development of hydrogel microparticles that can be used for clinical transformation.

Comparison of the effect of delaying progression of myopia in children with defocus incorporated multiple segments spectacle lenses and orthokeratology / 中华实验眼科杂志

Objective:To compare the effect of delaying progression of myopia in children between defocus incorporated multiple segments (DIMS) spectacle lens and orthokeratology.Methods:A nonrandomized controlled clinical study was conducted.A total of 390 children (390 eyes) with myopia who were treated in the First Affiliated Hospital of Zhengzhou University from January 2018 to December 2020 were included, with the spherical equivalent (SER) of -0.75 to -6.00 D. According to the willingness of patients and patients' guardians, the subjects were divided into DIMS group, orthokeratology group and single-vision spectacle lens group, with 130 cases (130 eyes) in each group, wearing DIMS spectacle lenses, standard or astigmatic design orthokeratology and conventional single-vision full-correction aspheric spectacle lenses, respectively.The SER of the eyes was measured using an automatic computerized refractometer in combination with subjective refraction before and one year after lens wear, and the axial length (AL) of the eyes was measured using IOLMaster.A total of 327 patients in the three groups met the inclusion and exclusion criteria, including 107 in the DIMS group, 112 in the orthokeratology group, and 104 in the single-vision spectacle lens group.All the right eyes were included in this study.The changes in SER and AL before and after wearing lenses for 1 year were compared among the three groups.The relationship between AL and SER changes and baseline data in the DIMS group was evaluated by Pearson linear correlation analysis.The study followed the Declaration of Helsinki, and the study protocol was reviewed and approved by the Ethics Committee of the First Affiliated Hospital of Zhengzhou University (No.2023-KY-0174-002). The subjects and their guardians were fully aware of the purpose and methodology of the study, and voluntarily signed an informed consent form.Results:There were statistically significant overall differences in SER and AL at different time points among the three groups (SER: Fgroup=7.065, P=0.009; Ftime=183.730, P<0.001.AL: Fgroup=6.151, P=0.014; Ftime=175.290, P<0.001). One year later, the differences in SER and AL changes among the three groups were statistically significant ( F=7.065, P=0.009; F=6.151, P=0.014). The SER and AL of each group after 1 year was greater than the baseline, with the SER and AL and their changes significantly smaller in orthokeratology group and DIMS group than in single-vision spectacle lens group and greater in DIMS group than in orthokeratology group, showing statistically significant differences (all at P<0.05). Compared with single-vision spectacle lenses, wearing orthokeratology for 1 year can inhibit SER and AL progression by 58.3% and 59.0%, and wearing DIMS frame glasses for 1 year can inhibit SER and AL progression by 46.9% and 43.6%.The percentage of eyes with no change in SER was 5.77%(6/104), 24.11%(27/112) and 17.76%(19/107) in the single-vision spectacle lens group, orthokeratology group and DIMS group, respectively, and the percentage of AL was 0.00%(0/104), 8.93%(10/112) and 7.48%(8/107), respectively, showing statistically significant differences among the three groups ( χ2=9.316, 8.676; both at P<0.001). The AL change in the DIMS group was weakly negatively correlated with age ( r=-0.252, P=0.006). Conclusions:Wearing DIMS spectacle lenses is not as effective as orthokeratology in delaying myopia in children, but it is significantly better than wearing conventional single-vision spectacle lenses.

Research progress on prediction models for myopia development / 国际眼科杂志(Guoji Yanke Zazhi)

Myopia is one of the leading causes of visual impairment and has become a major global public health concern with the rapidly increasing prevalence worldwide. Due to the trend of myopia towards younger age groups, accurate prediction of the occurrence and progression of myopia could help to provide targeted interventions for high-risk population and myopia patients in children and adolescents, in order to delay myopia onset or slow myopia progression. In recent years, various myopia prediction models have been built based on evidence-based medicine such as baseline ocular biometric data, refractive status, environment factors, genetic factors, and lifestyle have been established. The interaction of genetic and environmental effects on etiology of myopia have been established, with the continuous innovation of genetic research methods, specific genes with higher predictive power in the future will also be applied in the prediction, prevention and control of myopia. This article summarize the content, performance and research progress of myopia prediction models, which could serve as a useful reference and guidance for the prevention and control of myopia in children and adolescents.

Comparison of effective optical zone and corneal high order aberration following small incision lenticule extraction for different degrees of myopia / 国际眼科杂志(Guoji Yanke Zazhi)

AIM: To compare the effective optical zone(EOZ)and corneal high order aberrations(HOAs)after small incision lenticule extraction(SMILE)among low, moderate, and high myopic patients.METHODS:A total of 134 patients who had undergone SMILE at the Second People's Hospital of Foshan from February 2019 to February 2021 were recruited, with all right eyes enrolled. The patients were divided into low myopia group(SE &#x003E;-3.00 D), moderate myopia group(-6.00 D&#x003C; SE ≤-3.00 D), and high myopia group(SE ≤-6.00 D)according to the spherical equivalent(SE). The total HOA(tHOA), spherical aberration, coma, and EOZ were measured by Pentacam preoperatively and 1 mo postoperatively, and differences in tHOA, spherical aberration, coma, and EOZ among the three groups were analyzed.RESULTS: EOZ was smaller than programmed EOZ in all groups at 1 mo after SMILE. With the increase in corrected refractive error, the EOZ decreased further(P&#x003C;0.05); The tHOA, spherical aberration, and coma were significantly higher than their corresponding preoperative values in all groups at 1 mo after surgery, and there were statistical differences in the spherical aberration of all the groups at 1 mo after surgery(P&#x003C;0.05), except for that of the mild myopia group(P&#x003E;0.05). The tHOA, spherical aberration and coma increased with corrected refractive errors; the difference in tHOA and spherical aberration was statistically significant among the three groups(all P&#x003C;0.05). Coma in the high myopia group was significantly greater than that in the moderate myopia group and the mild myopia group(P&#x003C;0.05). In addition, the coma in the moderate myopia group and the mild myopia group was not statistically significant(P&#x003E;0.05).CONCLUSION: With the increase of the refractive power corrected by surgery, the postoperative EOZ reduced more after surgery, and the HOA of the cornea is increased; corneal HOA increases at 1 mo after SMILE.

Role of spherical aberration and coma in orthokeratology for myopia control / 国际眼科杂志(Guoji Yanke Zazhi)

As a highly prevalent global condition, myopia significantly impacts the ocular health of young individuals in China. Orthokeratology lens, as a rigid corneal contact lens, has demonstrated effective control over the progression of myopia; however, its mechanism of action remains incompletely elucidated. As one of the factors influencing visual acuity, higher-order aberrations will undergo marked changes after orthokeratology, with particular emphasis on the alterations in spherical aberrations and coma. The changes in corneal morphology induced by orthokeratology lead to significant positive increase in both spherical aberration and coma. Furthermore, the elevation of spherical aberration and coma demonstrates a negative correlation with the rate of axial length growth following orthokeratology. The interplay among spherical aberration, coma, defocus, accommodation, astigmatism, and pseudo-accommodation may constitute the underlying mechanism governing the control of myopia through orthokeratology.

Control effect of high aspherical lenticule in children and adolescents with low myopia / 国际眼科杂志(Guoji Yanke Zazhi)

AIM:To explore the effect of high aspherical lenticule on controlling low myopia.METHODS: Prospective study. A total of 100 patients aged 7 to 12 years old with low myopia who visited our hospital from May 1 to 31, 2022 were collected. They were divided into two groups with 50 cases in each group according to the wishes of patients. The control group was given single vision glasses after optometry, while the study group was given high aspherical lenticule. The myopia progression(absolute value), axial length(AL)growth, transition rate to moderate myopia, and AL negative growth rate over 6 mo and 1 a were compared between the two groups.RESULTS: The myopia progression and the AL growth of study group was lower than that of the control group after 6 mo and 1 a(all P&#x0026;#x003C;0.001).The negative growth rate of AL after 6 mo of treatment was significantly higher than that of the control group(P&#x0026;#x003C;0.001). The transition rate to moderate myopia between the two groups was not statistically significant(P=0.62); while the transition rate to moderate myopia in the study group was significantly lower than that in the control group after wearing lens for 1 a(P&#x0026;#x003C;0.001), and there was no statistically significant difference in AL negative growth rate between the two groups(P=0.12). Compare with single vision glasses, high aspherical lenticule achieved an 88.2% control rate for low myopia progression over 6mo and a 90.0% control rate of AL growth. The control rate for low myopia to moderate myopia was 66.7%; while the control rate of myopia progression growth was 75.6% after wearing lens for 1a, the control rate of AL growth was 69.2%, and the control rate of the transition rate to moderate myopia was 88.9%.CONCLUSION: For children and adolescents aged 7 to 12 with low myopia, high aspherical lenticule was more effective than single vision glasses in controlling myopia, making it one of the optimal choices for myopia control.

Clinical effect of defocusing frame lens on myopia control in adolescents / 中国现代医生

@#Objective To investigate the clinical effect of highly aspherical lenslets(HAL)in myopia control in adolescents.Methods Totally 101 cases(202 eyes)of adolescent myopia patients treated in ophthalmology outpatient department of our hospital from January 2021 to February 2022 were selected as the study objects.Of these,43 cases(86 eyes)wore HAL lenses as an observation group and 58 cases(116 eyes)wore single-vision spectacle lenses(SVL)as a control group.After 12 months of follow-up,the equivalent spherical lens degree and axial length were recorded in 6 months and 12 months respectively.Results The change of equivalent spherical lens in the HAL group was(-0.18±0.22)D and that in the SVL group was(-0.47±0.21)D,and the change in the HAL group was less than that in the SVL group,the difference was significant(P<0.001).The equivalent spherical lens degree in the HAL group was(-0.33±0.32)D and the HAL group was(-0.82±0.20)D at the 12th month,and the change in the HAL group was less than that in the SVL group,the difference was significant(P<0.001).The axial length of the eye in the HAL group was(0.09±0.09)mm and the SVL group was(0.20±0.07)mm in June,and the change in the HAL group was less than that in the SVL group,and the difference was significant(P<0.001).The axial length of the eye in the HAL group was(0.14±0.13)mm and that in the SVL group was(0.37±0.08)mm,and the change in the HAL group was less than that in the SVL group,and the difference was significant(P<0.001).Conclusion Wearing HAL lens for 12 months can effectively slow down the growth of myopia degree and axial length in adolescent myopia patients.

Deep Learning Image Recognition-assisted Atomic Force Microscopy for Precise and Efficient Detection of Single-cell Mechanical Properties / 生物化学与生物物理进展

ObjectiveThe advent of atomic force microscope (AFM) provides a powerful tool for the studies of life sciences. Particularly, AFM-based indentation assay has become an important method for the detection of cellular mechanics, yielding numerous novel insights into the physiological and pathological activities from the single-cell level and considerably complementing traditional biochemical ensemble-averaged assays. However, current AFM indentation technology is mainly dependent on manual operation with low efficiency, seriously restricting its practical applications in the field of life sciences. Here, a method based on the combination of deep learning image recognition and AFM is developed for precisely and efficiently detecting the mechanical properties of single isolated cells and clustered cells. MethodsThe YOLO deep learning algorithm was used to recognize the central region of the cell in the optical image, the dual UNet neural network with an embedded vision transformer (ViT) module was used to recognize the peripheral regions of cell, and the template matching algorithm was used to recognize the tip of spherical probe. Based on the automatic determination of the positional relationships between the microsphere tip and the different parts of cell, the AFM tip was accurately moved to the central and peripheral regions of the target cell for rapid measurements of cell mechanical properties. Two types of cells, including HEK 293 cell (human embryonic kidney cell) and HGC-27 cell (human undifferentiated gastric cancer cell), were used for the experiments. The Hertz model was applied to analyze the force curves obtained on cells to obtain cellular Young’s modulus. ResultsAFM probe can be precisely moved to the different parts (central areas and peripheral areas) of cells to perform mechanical measurements under the guidance of deep learning-based optical image automatic recognition. The experimental results show that the proposed method is not only suitable for single isolated cells, but also suitable for clustered cells. ConclusionThe research demonstrates the great potential of deep learning image recognition to aid AFM in the precise and efficient detection of cellular mechanical properties mechanics, and combining deep learning-based image recognition with AFM will benefit the development of high-throughput AFM-based methodology to measure the mechanical properties of cells.

Low-level red-light therapy for myopia control in children: A systematic review and meta-analysis

Abstract Introduction Low-Level Red-Light (LLRL) Therapy is a safe and natural way to promote healing and reduce inflammation in the body. When it comes to treating myopia in children, LLRL therapy is recent, and its efficacy and safety still are not clear. Methods A systematic review and meta-analysis of the literature for LLRL was conducted in accordance with the PRISMA guidelines on November 5, 2022. Databases, including PUBMED, Cochrane Library, Web of Science, and Embase were queried. A meta-analysis of random effects was conducted. Inclusion criteria included Randomized Controlled Trials (RCTs) or observational studies where LLRL therapy was used in children (3‒15 years old) with myopia. Exclusion criteria were studies with other ocular abnormalities. Efficacy was evaluated through the mean change in Axial Length (AL) and cycloplegic Spherical Equivalent Error (SER), while safety was evaluated by monitoring adverse effects. Results A total of 5 final studies were included (4 RCTs, and 1 observational), in which 685 total patients were analyzed. The mean age was 9.7 ± 0.66 years, with 48,2% female patients. The number of eyes in the LRLL arm is 714 and, in the control, arm is 656. LLRL showed better results in SER and AL mean change (OR = 0.58; 95% CI 0.33 to 0.83; p < 0.00001, and MD -0.33; 95% CI -0.52 to -0.13; p = 0.001, respectively), in comparison to the control group. There was no significant difference in adverse effects between groups (MD = 5.76; 95% CI 0.66 to 50.14; p = 0.11). Conclusion LLRL therapy is a non-invasive, effective, and safe short-term treatment option; however, long-term evaluation, particularly in comparison to other therapies, requires additional investigation.

Non-pathologic components are associated with reduced visual acuity in myopes after spectacle correction

Purpose: To find the association between reduced best?corrected visual acuity and non?pathologic components after optical correction in individuals with low to high myopia. Methods: Myopic children under 16 years of age were reviewed using electronic medical records and the following data were extracted and recorded: participant’s age, gender, uncorrected visual acuity (UCVA), manifest refraction, and best corrected visual acuity (BCVA). Spherical equivalent and cylinder were classified into low, moderate, and high categories based on the magnitude range. Similarly, astigmatism was defined into with?the?rule, against?the?rule, and oblique based on the location of the steepest meridian. Reduced BCVA was defined when the decimal visual acuity was less than 0.66 (equivalent to Snellen’s acuity of 6/9 or 20/30). Logistic regression was performed to test the factors associated with reduced visual acuity after optical correction in the absence of myopic pathologic changes. Statistical significance was considered if P < 0.05. Results: Overall 44.9% (N = 242/538) of myopes had reduced best?corrected visual acuity (BCVA) and none of the patients had pathologic myopic lesions. Using logistic regression, we found that high spherical refraction (OR 27.98, 95% CI 14.43–54.25, P < 0.001) and moderate spherical refraction (OR 5.52, 95% CI 2.56–11.91, P < 0.001) were significantly associated with reduced best corrected visual acuity despite any pathological lesions. Additionally, oblique and ATR astigmatism were associated with reduced visual acuity in myopic children with (OR 2.05, 95% CI 0.77–5.42) and (OR 1.59, 95% CI 0.82–3.08). Conclusion: Higher magnitude of refractive error components causes reduced visual acuity in the absence of pathologic changes.

Prediction of spherical equivalent refraction and axial length in children based on machine learning

Purpose: Recently, the proportion of patients with high myopia has shown a continuous growing trend, more toward the younger age groups. This study aimed to predict the changes in spherical equivalent refraction (SER) and axial length (AL) in children using machine learning methods. Methods: This study is a retrospective study. The cooperative ophthalmology hospital of this study collected data on 179 sets of childhood myopia examinations. The data collected included AL and SER from grades 1 to 6. This study used the six machine learning models to predict AL and SER based on the data. Six evaluation indicators were used to evaluate the prediction results of the models. Results: For predicting SER in grade 6, grade 5, grade 4, grade 3, and grade 2, the best results were obtained through the multilayer perceptron (MLP) algorithm, MLP algorithm, orthogonal matching pursuit (OMP) algorithm, OMP algorithm, and OMP algorithm, respectively. The R2 of the five models were 0.8997, 0.7839, 0.7177, 0.5118, and 0.1758, respectively. For predicting AL in grade 6, grade 5, grade 4, grade 3, and grade 2, the best results were obtained through the Extra Tree (ET) algorithm, MLP algorithm, kernel ridge (KR) algorithm, KR algorithm, and MLP algorithm, respectively. The R2 of the five models were 0.7546, 0.5456, 0.8755, 0.9072, and 0.8534, respectively. Conclusion: Therefore, in predicting SER, the OMP model performed better than the other models in most experiments. In predicting AL, the KR and MLP models were better than the other models in most experiments.

Effectiveness of 0.01% atropine in anisomyopic children

Purpose: To investigate the change in ocular parameters of anisomyopic children treated with 0.01% atropine. Methods: This retrospective study analyzed the data of anisomyopic children who underwent comprehensive examination at a tertiary eye center in India. Anisomyopic subjects (difference of ?1.00 D) of age 6–12 years who were treated with 0.01% atropine or prescribed regular single vision spectacle and had follow?ups of more than 1 year were included. Results: Data from 52 subjects were included. No difference was observed in the mean rate of change of spherical equivalent (SE) of more myopic eyes between 0.01% atropine (?0.56 D; 95% confidence interval [CI]: ?0.82, ?0.30) and single vision lens wearers (?0.59 D; 95% CI: ?0.80, ?0.37; P = 0.88). Similarly, insignificant change in the mean SE of less myopic eyes was noted between the groups (0.01% atropine group, ?0.62 D; 95% CI: ?0.88, ?0.36 vs. single vision spectacle wearer group, ?0.76 D; 95% CI: ?1.00, ?0.52; P = 0.43). None of the ocular biometric parameters showed any difference between the two groups. Though anisomyopic cohort treated with 0.01% atropine revealed a significant correlation between the rate of change of mean SE and axial length in both eyes (more myopic eyes, r = ?0.58; P = 0.001 and less myopic eyes, r = ?0.82; P < 0.001) compared to single vision spectacle wearer group, the change was not significant. Conclusion: Administration of 0.01% atropine had minimal effect on reducing the rate of myopia progression in anisomyopic eyes.

Impacto de la COVID-19 en la progresión de la miopía en niños / Impact of COVID-19 on myopia progression in children

Introducción: La Organización Mundial de la Salud considera a la miopía un problema de salud mundial debido a su prevalencia creciente. Se espera que afecte al 52 % de la población mundial en 2050. Objetivo: Determinar la progresión de la miopía durante la pandemia de COVID-19 con respecto al período previo al confinamiento. Métodos: Se realizó un estudio descriptivo y ambispectivo de una serie de 12 pacientes atendidos en la Consulta de Oftalmología Pediátrica del Instituto Cubano de Oftalmología "Ramón Pando Ferrer" antes de la pandemia y que acudieron en el período de confinamiento por la COVID-19 para su seguimiento. Las variables evaluadas fueron edad, género, antecedentes patológicos familiares de miopía, horas pantalla, equivalente esférico y biometría. Resultados: El promedio de edad fue de 9,7 años y el 58,3 por ciento correspondió al sexo femenino. El 75 por ciento de los pacientes tenían antecedentes patológicos familiares de miopía y el tiempo estimado frente a pantalla fue de 5,3 ± 0,8 h diarias. La media de la biometría se incrementó en el tiempo de 23 mm en 2019 a 25,5 mm en 2021. La diferencia de la media del equivalente esférico previo a la COVID-19 fue -0,89 y -0,84 para ojo derecho y el ojo izquierdo, respectivamente. En la etapa epidémica se percibió un aumento hasta -1,97 y -1,72. Conclusiones: El incremento del uso de los medios digitales debido al confinamiento ha causado la progresión de la miopía(AU)

Introduction: Myopia is considered a global health problem by the World Health Organization due to its increasing prevalence and is expected to affect 52 percent of the world's population by 2050. Objective: To determine the progression of myopia during the COVID-19 pandemic with respect to the pre-confinement period. Methods: A descriptive and ambispective study of a series of 12 patients treated at the Pediatric Ophthalmology Clinic of the Cuban Institute of Ophthalmology "Ramón Pando Ferrer" before the pandemic and who visited the hospital during the COVID-19 confinement period for follow-up, was carried out. The variables evaluated were age, gender, family history of myopia, screen hours, spherical equivalent and biometry. Results: The average age was 9.7 years and 58.3 percent of the patients were females. Seventy-five percent of the patients had a family history of myopia and the estimated time in front of the screen was 5.3 ± 0.8 h per day. The medium biometry increased over time from 23 mm in 2019 to 25.5 mm in 2021. The difference in medium pre-COVID-19 spherical equivalent was -0.89 and -0.84 for right eye and left eye, respectively. In the epidemic stage, an increase to -1.97 and -1.72 was perceived. Conclusions: Increased use of digital media due to confinement has caused myopia progression(AU)

Comparison of the effects between toric-designed and spherical orthokeratology for the control of moderate-to-low myopia in adolescents / 国际眼科杂志(Guoji Yanke Zazhi)

AIM: To compare the control effects between toric-designed orthokeratology and spherical orthokeratology on adolescents with moderate-to-low myopia.METHODS: The clinical data of 169 adolescents(290 eyes)with moderate-to-low myopia in Jiayuan Outpatient Department of Shanghai Demu Ophthalmology from July 2020 to June 2021 were analyzed retrospectively. The patients were divided into toric group and spherical group according to the type of orthokeratology, with 81 cases(135 eyes)and 88 cases(155 eyes)respectively. The changes of visual acuity and ocular axis before and after treatment were recorded to evaluate the therapeutic effect.RESULTS: The uncorrected visual acuity of both groups significantly improved at 1a after treatment(P&#x003C;0.01), and the axial length increased compared to that before treatment(P&#x003C;0.01). But there were no significant differences in uncorrected visual acuity(0.014±0.043, 0.017±0.047LogMAR)and axial growth(0.18±0.22, 0.19±0.22mm)between the two groups(P&#x003E;0.05).CONCLUSION: Both toric-designed orthokeratology and spherical orthokeratology can improve the uncorrected visual acuity of adolescents with low-to-moderate myopia, and there is no significant difference in controlling effect on myopia.

Analysis of refractive parameters and theirs correlation with spherical equivalent in preschool children aged 3 to 6 years / 国际眼科杂志(Guoji Yanke Zazhi)

AIM: To investigate the distribution of refractive parameters and theirs correlation with spherical equivalent(SE)in preschool children aged 3 to 6 years, and evaluate the accuracy of each screening index in diagnosing refractive errors.METHODS: Cross-sectional study. A total of 791 preschool children, ranging from 3 to 6 years old, who consented to undergo mydriatic refraction were selected. Axial length(AL), corneal refractive power(K), and SE were measured after microcoria optometry and mydriatic optometry. Additionally, the corneal radius of curvature(CR)and the axial length/corneal radius of curvature(AL/CR)ratio were calculated.RESULTS: A total of 791 students participated in the study, out of which 400(50.6%)were male and 391(49.4%)were female. The mean values for AL, CR, AL/CR, and SE were 22.62±0.94mm, 7.81±0.29mm, 2.90±0.09, and +1.95±1.31D, respectively. AL, CR, and AL/CR increased with age. AL and CR were significantly higher in males than in females(all P&#x003C;0.001), while there was no statistically significant difference between AL/CR and SE in males and females(P=0.82, 0.19). The correlation coefficients of SE and AL/CR, AL and CR were -0.86, -0.50 and 0.16, respectively. The results of multiple linear regression analysis indicate that for each unit increase in AL/CR, there was a corresponding shift of 10.91 towards myopia in SE. The sensitivity of AL/CR in screening for myopia was 94.44%, with a specificity of 90.46% and a Youden index of 0.84. For screening myopia under microcoria optometry, the sensitivity was 100%, with a specificity of 66.09% and a Youden index of 0.66. The area under the curve was 0.967 and 0.809 when the ROC curves were plotted using AL/CR and AL as indicators for screening myopia, respectively.CONCLUSION: For large group screening activities where mydriatic optometry is not feasible, AL/CR is better for evaluating refractive status and identifying children with myopia and hyperopia reserve that are lower than normal for their age, compared to AL and microcoria optometry.

Prevalence and risk factors of tessellated fundus in Tianjin Medical University students / 中华眼底病杂志

Objective:To investigate the prevalence and risk factors of tessellation fundus (TF) among Tianjin Medical University students with different refractive statuses.Methods:A cross-sectional study. From September to December 2019, 346 students from Tianjin Medical University were randomly selected and underwent slit-lamp examination, non-cycloplegic auto-refraction, subjective refraction, best-corrected visual acuity, ocular biometric measurement, and non-dilation fundus photography. The differences in the prevalence of TF in basic characteristics and ocular biometric parameters were compared. Based on the equivalent spherical (SE), refractive status was divided into the non-myopia group (SE>-0.50 D) and the myopia group (SE≤-0.50 D). The myopia group was further divided into mild myopia group (-3.00 D<SE≤-0.50 D), moderate myopia group (-6.00 D<SE≤-3.00 D), and high myopia group (SE≤-6.00 D). According to the axis length (AL), the subjects were divided into AL<24 mm group, 24-26 mm group, and >26 mm group. The logistic regression was used to analyze the risk factors affecting TF. Trend tests were performed for each risk factor and TF.Results:Of the 346 subjects, 324 (93.6%, 324/346) were myopia, of whom 73 (21.1%, 73/346), 167 (48.3%, 167/346), and 84 (24.3%, 84/346) were mild myopia, moderate myopia, and high myopia, respectively; 22 (6.4%, 22/346) were non-myopia. There were 294 (85.0%, 294/346) students with TF in the macula, including 9 (40.91%, 9/22), 58 (79.45%, 58/73), 145 (86.83%, 145/167), and 82 (97.62%, 82/84) in non-myopia, low myopia, moderate myopia, and high myopia group, respectively; 52 (15.0%, 52/346) students were without TF in the macula. There were statistically significant gender differences ( χ2=4.47), SE ( t=6.29), AL ( t=-8.29), anterior chamber depth ( Z=-2.62), lens thickness ( Z=-2.23), and average corneal radius ( Z=-3.58) between students with and without TF in the macula ( P<0.05). Spherical equivalent and axial length were independent risk factors for TF and its severity ( P≤0.001). With an increasing degree of myopia, and increasing axial length, the risk of TF increased ( P for trend<0.001). Conclusions:The prevalence of TF is 85.0% among Tianjin Medical University students. TF is detected in the fundus of no myopia, mild myopia, moderate myopia and high myopia. The degree of myopia is higher, the AL is longer, the possibility of TF is higher.

Effects of low-energy red light on choroidal thickness and spherical equivalent and axial length in myopic children / 国际眼科杂志(Guoji Yanke Zazhi)

AIM: To systematically evaluate the effects of low-energy red light on choroidal thickness(ChT), spherical equivalent(SE), and axial length(AL)in myopic children.METHODS: A total of 8 databases, including Pubmed, Embase, Cochrane Library, Web of Science, CNKI, WanFang Database, VIP Database and China Biomedical Literature Database, were electronically retrieved to collect the clinical randomized controlled trial(RCT)of low-energy red light in myopia, with red light intervention as an experimental group and glasses as a control group. The retrieval time limit is from the establishment of the database to January 2023. According to the recommendation of the Cochrane Handbook, literature quality and risk of bias were evaluated. Revman5.4 software was used for Meta-analysis.RESULTS: Totally 8 RCT about red-light treatment with myopia were included. The sample size for ChT analysis contained 407 eyes in the red-light group and 425 eyes in the control group; SE analysis included 490 eyes in the red-light group and 518 eyes in the control group; sample size for AL analysis were 518 eyes in the red-light group and 539 eyes in the control group. The differences in ChT, SE and AL between the groups were statistically significant(ChT: WMD=37.81, 95%CI: 21.55～54.07, P&#x003C;0.001; SE: WMD=0.58, 95%CI: 0.46～0.71, P&#x003C;0.001; AL: WMD=-0.31, 95%CI: -0.39～-0.24, P&#x003C;0.001).CONCLUSION: Specific red light can promote the increase of ChT while inhibit SE and AL. However, its long-term efficacy and side effects remain unclear. The above conclusions need to be further clarified by more RCT with large samples.

Effect of atropine 0.01% on progression of myopia

Purpose: Myopia is the most common type of refractive error and the leading cause of functional visual loss. Increased risk of myopic maculopathy, retinal detachment, glaucoma and cataract has been seen with a myopia of as low as ?1D. This study was done to determine the effect of atropine 0.01% eye drops on the progression of myopia in children >5 years. Methods: This was a single?blind, prospective, randomized case–control study which included children of 5–15 years with myopia of >2D and were divided into treatment group (group 1) and placebo group (group 2). Children under treatment group were treated with application of 0.01% atropine at night. Children with history of any ocular surgery, chronic ophthalmic illness, squint and amblyopia were excluded from the study. The follow?up for myopia progression was done for two years. Results: This study showed a significant difference in increase of spherical equivalent and axial length among treatment and placebo groups after a duration of two years. Total duration of follow up was twenty?four months. Mean increase in axial length of group 1 and 2 was 0.115 mm and 0.32 mm, respectively. Mean increase in refraction of groups 1 and 2 was ?0.30 D and ?0.88 D, respectively, showing significant change in axial length and refraction (P < 0.0001). Conclusion: This study supports the use of atropine 0.01% eye drops in reducing the progression of myopia.

Effects on ocular aberration and contrast sensitivity after implantation of spherical and aspherical monofocal intraocular lens - A comparative study

Purpose: Phacoemulsification with intraocular lens (IOL) implantation is the standard of care for cataractous eyes. Monofocal IOLs are spherical or aspheric. The aspheric design of IOLs reduces the spherical and higher-order aberrations and impacts contrast sensitivity post cataract surgery. There are some studies, but data in the Indian setting with the IOLs we used is lacking. We aimed to compare the effect of implantation of spheric and aspheric foldable intraocular lenses on postoperative quality of vision, spherical aberration, and contrast sensitivity. Methods: This prospective observational study was conducted at a tertiary care hospital with an ophthalmology specialty, data collection from January 2017 to May 2018 in 100 patients. Patients meeting the inclusion criteria were selected. Their preoperative and postoperative data were collected and divided into groups based on whether spherical or aspheric IOL was implanted after cataract surgery. Variables assessed were visual acuity on days 7 and 30, spherical aberrations, and contrast sensitivity was assessed at 1?month postoperative. Results: The mean age of the patients in this study was 64 ± 8 years with a majority of patients (60%) being females. There is no significant difference in postoperative visual acuity between the two groups. Internal SA was significantly lower (~50%) in eyes implanted with aspheric IOLs (P value = 0.004, 0.0001) compared with the spherical group. Contrast sensitivity of patients of the aspheric group was significantly better (P value <0.05). Conclusion: The optical design of the aspheric IOLs reduced spherical aberrations and increased contrast sensitivity.

The Effect of Monochromatic Aberrations of the Cornea on Contrast Sensitivity under Photopic and Mesopic Conditions

Purpose: Vision is one of the most important senses. The first stage of vision is the creation of the observed object抯 image on the retina. The quality of the retinal image is affected by several factors, such as diffraction, sampling on the retina, chromatic aberration, scattering and higher order aberrations. The measurement of the quality is achieved both with subjective (visual acuity, contrast sensitivity) and objective methods (PSF, MTF, Strehl ratio, RMS). The purpose of this project is the measurement of higher order aberrations of the anterior corneal surface (with a Placido corneal topographer) and of the contrast sensitivity (with a Pelli Robson optotype). Then, we will try to find if there is a correlation between them.Methods and Materials: 20 persons participated in this survey, divided in two groups of 10 persons each. The first group (group 1) included subjects up to 39 years old and the second group (group 2) from 40 years and up. The participants didn抰 have any pathological problems, except lower order refractive errors. Both eyes of each individual were included in the procedure. First, the higher order aberrations of the anterior corneal surface were measured, with the implementation of a Placido corneal topographer. This was followed by a measurement of the contrast sensitivity. The whole procedure took place under two lighting conditions, both photopic and mesopic. The examination presentation of the higher order aberrations is performed with the use of Zernike polynomials.Results: The results of the measuring procedure showed that for the first group, under photopic conditions (luminance 32.70 cd/m2) the mean value (� standard deviation) for the higher order aberrations RMS and decimal logarithm contrast sensitivity was 0.073 � 0.018?m and 1.54 � 0,16 (contrast 2.88 � 1.24%) respectively. For the second group the corresponding values were 0.080 � 0.036?m and 1.59 � 0.16 (contrast 2.57 � 1.24%). Accordingly, under mesopic conditions (luminance 1.14 cd/m2) the values for the first group were 0.252 � 0.064 ?m and 1.27 � 0.15 (contrast 5.37 � 2.06%), while for the second were 0.253 � 0.069?m and 1.32 � 0.12 (contrast 4.79 � 1.35%). Spherical aberration and coma (horizontal and vertical) were also measured for both groups under photopic and mesopic conditions. The results showed that for the first group, under photopic conditions, RMS for coma and spherical aberration is 0.033 � 0.014 ?m and 0.022 � 0.011 ?m respectively, while for the second group 0.041 � 0.027 ?m and 0.024 � 0.008 ?m. Under mesopic conditions, the relevant results are 0.139 � 0.065 ?m and 0.124 � 0.035?m for the first group and 0.149 � 0.066 ?m and 0.107 � 0.038 ?m for the second group.Finally, we should mention here that the equivalent defocus error corresponding to the higher order aberration RMS was estimated. The results for all the participants (without age separation), are 0.23 � 0.09D (photopic conditions) and 0.28 � 0.07D (mesopic conditions).Conclusions: From the statistical analysis of the results we conclude that there exists a symmetry between left and right eyes regarding higher order aberrations. Furthermore, it seems that age is not a significant factor for differences on the magnitude of higher order aberrations both under photopic and mesopic conditions as well. Similar conclusions are also reached for the contrast sensitivity measurements. In addition, we have observed that a correlation exists between the higher order aberrations of the anterior corneal surface and the contrast sensitivity, for both photopic and mesopic conditions. Correlation also exists between coma and contrast only under photopic conditions. But there is no significant correlation between spherical aberration and contrast. The age difference of these two groups has not an effect on the results. Finally, the equivalent defocus is too small, both for photopic and mesopic conditions and between each other, in order to be clinically significant.