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<0.001).The negative growth rate of AL after 6 mo of treatment was significantly higher than that of the control group(P<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<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.

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.

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)

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.

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.

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.

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.

Miopía en pacientes con retinopatía de la prematuridad / Myopia in patients with Retinopathy of Prematurity

Objetivos: describir el comportamiento del defecto miópico hasta el año de vida, en pacientes que desarrollaron retinopatía de la prematuridad, y determinar los principales factores de riesgo del mismo. Método: se realizó un estudio descriptivo, longitudinal, prospectivo en 37 pacientes que, habiendo sido tratados o no por retinopatía de la prematuridad, mantuvieron un seguimiento estable en consulta posterior a la fase aguda de la enfermedad. Fueron evaluadas a los seis y 12 meses de vida teniendo en cuenta las variables edad gestacional al nacer, peso al nacer, tipo de retinopatía de la prematuridad, presencia de miopía. Resultados: la mediana de edad gestacional y peso al nacer fueron 30,2 semanas y 1 287 g. A los seis meses cinco ojos de 27 pacientes (considerando solo los ojos derechos) presentaron miopía, lo cual representa el 18,5 por ciento. A los 12 meses este valor se incrementó a 44,4 por ciento. La edad gestacional y el peso al nacer no mostraron relación con el desarrollo de miopía (p = 0,072 y p = 0,397) a los 12 meses. En pacientes con retinopatía de la prematuridad grave el defecto miópico resultó más frecuente (p = 0,003). Conclusiones: la prematuridad y el peso al nacer no constituyeron variables que influyeran en la aparición de miopía. Por el contrario, la retinopatía de la prematuridad grave sí se asoció con una mayor miopía, sobre todo a los 12 meses(AU)

Objectives: to describe the behavior of the myopic defect up to one year of life, in patients who developed retinopathy of prematurity, and to determine the main risk factors for it. Method: a descriptive, longitudinal, prospective study was carried out in 37 patients who, having been treated for retinopathy of prematurity or not, maintained a stable follow-up in consultation after the acute phase of the disease. They were evaluated at 6 and 12 months of life taking into account the variables gestational age at birth, birth weight, type of retinopathy of prematurity, presence of myopia. Results: Median gestational age and birth weight were 30.2 weeks and 1287g. At 6 months, 5 eyes of 27 patients (considering only the right eyes) presented myopia, which represents 18.5 percent. At 12 months this value increased to 44.4 percent. Gestational age and birth weight were not related to the development of myopia (p = 0.072) and p = 0.397) at 12 months. In patients with severe retinopathy of prematurity, myopic defect was more frequent (p = 0.003). Conclusions: prematurity and birth weight were not variables that influenced the appearance of myopia. On the contrary, severe retinopathy of prematurity was associated with greater myopia, especially at 12 months(AU)

Nomogram of peripapillary retinal nerve fiber layer thickness in myopic eyes of north Indian population

Purpose: To evaluate peripapillary?RNFL thickness in myopia by Cirrus OCT among north Indian population by spherical equivalent (SE), age, gender, and axial length (AL). Methods: This was a cross? sectional study held during 2019–2020. Patients aged 18–60 years underwent ophthalmic examination including retinoscopy, AL, and OCT RNFL thickness. Persons with previous ocular surgery or ocular ailment other than refractive error were excluded. The peripapillary?RNFL thickness was noted and compared by demographic determinants. Results: We examined 300 eyes of 300 persons (mean age: 30.75 ± 8.57 years; 144 males/156 females). Among them, 224 were myopes and 76 were emmetropes (EM). The mean SE was ? 3.3 ± 0.4D (range: ?11.0D to + 0.37D). The mean AL was 24.61 ± 1.92 mm (22.1–29.5). Overall temporal, nasal, superior, inferior, and mean peripapillary?RNFL thickness was 66.31 ± 7.58, 78.57 ± 16.00, 120.63 ± 11.69, 116.60 ± 15.80, and 95.50 ± 10.84 ?m, respectively. Temporal, nasal, superior, inferior, and mean peripapillary?RNFL thickness was 73.97 ± 8.36, 94.84 ± 7.63, 127.96 ± 8.96, 136.89 ± 6.53, and 108.34 ± 6.28 ?m, respectively, in EM eyes as compared to 63.71 ± 6.18, 73.05 ± 14.24, 118.21 ± 11.53, 109.71 ± 11.50, and 91.14 ± 8.31 ?m, respectively, in myopic eyes (P < 0.001). Association of peripapillary?RNFL thickness with myopia and its different grades was P < 0.001. Association of mean peripapillary?RNFL thickness with age was P > 0.005 and gender was P = 0.168. Correlation between SE and RNFL thickness was positive and significant. Correlation between AL and RNFL thickness was negative but statistically significant. Association of AL with SE was P < 0.001. Conclusion: We provide normative peripapillary?RNFL thickness in the north Indian population in order to help in screening for myopia with comorbidity such as glaucoma based on RNFL thickness.

Comparison of visual performance of monofocal intraocular lenses with different asphericities

Objective@#To compare the visual performance and patient-reported outcomes of three types of monofocal intraocular lenses (IOL) with different asphericities.@*Methods@#This cross-sectional, comparative study comprised of 62 pseudophakic eyes divided into three groups corresponding to the IOL that they were previously implanted with (Tecnis ZCB00 negative aspheric IOL, EnVista MX60 neutral aspheric IOL and Akreos Adapt spheric IOL). Mean refractive spherical equivalent (MRSE), best-corrected far visual acuity (BCVA), spherical aberration (SA), contrast sensitivity (SC), halo and starburst, and responses to a qualitative questionnaire (NEI-RQL) were measured.@*Results@#There was no significant difference in MRSE (P=0.74) and BCVA (P=0.52) among the three groups. There was a statistically significant difference (P=0.00) in mean internal (lens) SA, measured through a 5mm pupil, among Tecnis (-0.150 μm), EnVista (+0.022 μm) and Akreos Adapt (+0.094 μm). Compared to the Akreos Adapt, the Tecnis and EnVista groups had significantly better CS at 6 CPD and 12 CPD under mesopic testing without glare (P= 0.01) and at 6 CPD mesopic testing with glare (P=0.04). Halo scores were insignificant among the three groups. However, starburst scores were significantly worse in the Akreos Adapt IOL than the Tecnis and EnVista (P=0.01). There was no difference in questionnaire responses among the three groups.@*Conclusion@#The negative aspheric and neutral aspheric lenses showed significantly lower SA resulting in better CS in mesopic conditions and better starburst scores. MRSE, BCVA and subjective satisfaction were statistically similar regardless of the type of monofocal intraocular lens

Fiber direction estimation using constrained spherical deconvolution based on multi-model response function / 生物医学工程学杂志

Constrained spherical deconvolution can quantify white matter fiber orientation distribution information from diffusion magnetic resonance imaging data. But this method is only applicable to single shell diffusion magnetic resonance imaging data and will provide wrong fiber orientation information in white matter tissue which contains isotropic diffusion signals. To solve these problems, this paper proposes a constrained spherical deconvolution method based on multi-model response function. Multi-shell data can improve the stability of fiber orientation, and multi-model response function can attenuate isotropic diffusion signals in white matter, providing more accurate fiber orientation information. Synthetic data and real brain data from public database were used to verify the effectiveness of this algorithm. The results demonstrate that the proposed algorithm can attenuate isotropic diffusion signals in white matter and overcome the influence of partial volume effect on fiber direction estimation, thus estimate fiber direction more accurately. The reconstructed fiber direction distribution is stable, the false peaks are less, and the recognition ability of cross fiber is stronger, which lays a foundation for the further research of fiber bundle tracking technology.

Epidemiological study on myopia among primary school students in Xindu District of Chengdu in 2018-2020 / 国际眼科杂志(Guoji Yanke Zazhi)

@#AIM: To observe the epidemiological characteristics of myopia among primary school students in Xindu District of Chengdu before and after COVID-19 home isolation period(from Jan.-May 2020).<p>METHODS:Cross-sectional study. A total of 10 153 primary school students from grade 1-6(age 6-13, three classes per grade)were selected from four primary schools in Xindu District of Chengdu for three consecutive years(2018-2020), by using a random stratified cluster sampling method. All students' visual acuity and spherical equivalent refraction(SE)were measured, a further cycloplegia optometry was conducted for those whose visual acuity was less than 5.0. The SE was recorded and the prevalence of myopia was calculated. Chi-square test was used to compare the difference of prevalence of myopia between different years. One-way Anova was used to compare the difference of SE among different years.<p>RESULTS: There was statistical difference in prevalence of myopia between the three years(2018: 35.98%, 2019: 36.29%, 2020: 42.52%; χ²=39.374, <i>P</i><0.001). The prevalence of myopia among 6-9 years old students increased significantly in 2020(<i>P</i><0.01). They were 2.20 times(6 years old), 2.08 times(7 years old), 1.36 times(8 years old)and 1.24 times(9 years old)of the previous year. Students aged 6-9 years showed an obvious myopic shift in SE in 2020(<i>P</i><0.05). The increases were -0.34±0.76D(6 years old), -0.28±0.84D(7 years old), -0.29±1.41D(8 years old)and -0.18±1.35D(9 years old)than the previous year. The prevalence of myopia and SE remained stable among 10-13 years old students in 2018-2020(<i>P</i>>0.05).<p>CONCLUSION: After the COVID-19 home isolation period, there was a significant myopic shift among students aged 6-9 years old. We should pay more attention to the window period for myopia prevention and control of 6-9 years old.

Ocular dominance switches after small incision lenticule extraction and its influencing factors / 中华实验眼科杂志

Objective:To investigate the changes, distribution and influencing factors of ocular dominance after small incision lenticule extraction (SMILE).Methods:A retrospective observational case series study was conducted.One hundred and twelve patients (224 eyes) with an average age of 25.1±5.4 years who underwent SMILE surgery at Tianjin Eye Hospital from November 2017 to February 2018 were enrolled.There were 42 male and 70 female patients.The dominant eye was determined using the hole-in-the-card test before and after the surgery.Subjective and objective refraction and uncorrected visual acuity examination were performed before operation, and 1 day, 1 week, 1 month and 3 months after operation.The subjects were divided into switch group and non-switch group based on whether the dominant eye changed after surgery.Binary logistic regression was used to analyze the main influencing factors of dominant eye switches.This study adhered to the Declaration of Helsinki.The study protocol was approved by the Ethics Committee of Tianjin Eye Hospital (No.201905). Written informed consent was obtained from each patient before any medical examination.Results:There were 18 patients (16.1%) in the switch group including 7 males (38.9%) and 11 females (61.1%), and 94 patients (83.9%) in the non-switch group including 35 males (37.2%) and 59 females (62.8%). No statistically significant difference was found in sex between the two groups ( χ2=0.02, P=0.89). At 1 month and 3 months after the surgery, there was a statistically significant difference in the cylindrical power between the dominant and non-dominant eye ( t=2.31, 1.95; both at P<0.05). Binary logistic regression equation showed that spherical equivalent[odds ratio ( OR)=0.47, 95%confidence interval ( CI): 0.35-0.66]and refractive error difference ( OR=3.04, 95% CI: 2.12-4.36) were significantly related to the eye dominance switches. Conclusions:There were 16.1% of patients having eye dominance switches after SMILE.The dominant eye transfomation is associated with higher spherical equivalent and anisometropia difference before surgery.

Investigation of fetal cardiac function and morphology in fetuses with left ventricular outflow tract obstruction using fetal heart quantification / 中华超声影像学杂志

Objective:To explore the application value of fetal heart quantification (fetal HQ) in evaluation of fetal cardiac function and morphology in fetuses with left ventricular outflow tract obstruction (LVOTO).Methods:Twenty-five fetuses with LVOTO diagnosed by fetal echocardiography in Sir Run Run Shaw Hospital, Zhejiang University Medical College from April to July 2020 were enrolled. The end-diastolic basal apical length(BAL), transverse length (TL), global spherical index (GSI) of fetal four-chamber view, and the left and right ventricular end-diastolic area, long diameter, 24-segment end-diastolic transverse length (ED) and its Z-scores adjusted by gestational age and 24-segment spherical index(SI) were calculated by using fetal HQ. Subsequently the Z-scores of left and right ventricle fractional shortening (FS) in 24 segments were obtained by gestational age.Results:SI of 24-segments of left ventricles in fetuses with LVOTO were significantly different from that of right ventricles (all P<0.05). There was significant difference between left and right ventricular areas ( P<0.05). There was no significant difference between left and right ventricular lengths ( P>0.05). There were significant differences between the 24-segment Z-scores of left and right ventricular ED(all P<0.05). The ratios of RVED to LVED of 24 segments were analyzed by box diagram. The results showed that the transverse length of right ventricle was significantly higher than that of left ventricle. The highest value was 1.49(1.26-1.86), and the lowest value was 1.40(1.26-1.86), both significantly higher than the normal value of 1.19. There were no significant differences between the 1-19-segment Z-scores of left and right ventricular FS( P>0.05). There were significant differences between the 20-24-segment Z-scores of left and right ventricular FS( P<0.05). Conclusions:Fetal HQ can be used to quantitatively analyze left ventricular shape, size and function of fetuses with LVOTO, which provides a new method for quantitative analysis of fetal heart function.