Myopia Group Research Articles

The Association of Myopia Progression with Changes in Retinal Thickness among Primary School Students with Myopia.

To observe the relationship between myopia progression and changes in retinal thickness during one year of follow-up among primary school children. The study included 1161 eyes of 708 myopic children, with 616 (53.06%) right eyes and 545 (46.94%) left eyes. The participants underwent a comprehensive ophthalmic examination, including visual acuity, axial length (AL), autorefraction, and optical coherence tomography (OCT) examination in 2016 and in 2017. An analysis was conducted on the differences in retinal thickness between different genders and between high myopia and nonhigh myopia. Furthermore, the study delved into the correlation between the progression of myopia and the changes of retinal thickness. The average diopter was -1.83 ± 1.29D, average AL was 23.78 ± 0.94 mm, and average foveal thickness was 228.02 ± 23.00 μm. For the inner retina, the median value [the lower quartile value, the upper quartile value] of the foveal thickness was thicker in the high myopia group than the nonhigh myopia group (67 [64; 74] μm vs. 63 [56; 70] μm), while the parafoveal region and perifoveal region were thinner in the high myopia group than the nonhigh myopia group (106 [100; 123] μm vs. 124 [117; 130] μm; 95.0 [93; 102] μm vs. 104 [100; 108] μm). Among all the children with myopia, 67.53% (784/1161) of them have a diopter progression within one year. The AL progression was 95.43% (1108/1161). The retinal thickness of all children has slightly increased in various regions. As the AL of the eye increased and the diopter decreased, the progression degree of inner retinal thickness and full retinal thickness (exclusive of full fovea) decreased. For the school-age myopic children, the inner foveal retinal thickness were thicker in highly myopic students than in the nonhighly myopic students, while the parafoveal and perifoveal retina were thinner in highly myopic students. The inner and full retinal thicknesses of male students were thicker than that of females. The progression of myopia mainly affected the changes of the inner retinal thickness in the one-year follow-up.

Characteristics of Peripheral Retinal Refraction and Its Role in Children with Different Refractive States.

Peripheral retinal refraction plays a crucial role in myopia, but the specific mechanism is not clear. We refined the retinal partitions to explore the characteristics of peripheral retinal refraction and its role in emmetropic, low, and moderate myopic children aged 6 to 12 years. A total of 814 subjects (814 eyes) were enrolled in the study. The participants were divided into three groups according to the central spherical equivalent refraction (SER), which were emmetropia group (E), low myopia group (LM) and moderate myopia group (MM). Multispectral refractive topography (MRT) was used to measure the retinal absolute and relative refractive difference value (RDV) in different regions. The range was divided into superior, inferior, temporal, and nasal RDV (SRDV, IRDV, TRDV, and NRDV) on the basis of several concentric circles extending outward from the macular fovea (RDV15, RDV30, RDV45, RDV30-15, RDV45-30, and RDV-45). Kruskal-Wallis test was used to analyze the differences of peripheral refraction for all the regions among the three groups. Spearman rank correlation was performed to explore correlations between SER and RDV, axial length (AL) and RDV. The absolute value of RDV decreased with increasing degree of myopia in all regions (P < 0.01). Subjects with different refractive degrees had different relative value of RDV. In nasal position within 45° and temporal position within 30°, the peripheral retina exhibited significantly different relative hyperopic refractive status among Group E, Group LM, and Group MM (P < 0.05). SER was negatively correlated with NRDV within 30° (especially in the range of NRDV30-15) (r = -0.141, P < 0.01), positively correlated with TRDV within 15° (r = 0.080, P = 0.023), and not significantly correlated with SRDV and IRDV when the retina was divided into four parts. AL was positively correlated with NRDV within 30° (especially in the range of NRDV30-15) (r = 0.109, P = 0.002), negatively correlated with TRDV within 15° (r = -0.095, P = 0.007). The peripheral defocus has significant implications for the genesis of myopia. The peripheral defocus of the horizontal direction, especially within the range of NRDV30, has greater effect on the development of myopia in children. Higher NRDV30 is associated with lower SER and longer AL.

Corneal stress-strain index in myopic Indian population.

The purpose is to study the corneal stress-strain index (SSI) in myopic refractive error among Indian subjects. A retrospective study where young myopic subjects aged between 11 and 35 years who had undergone corneal biomechanics assessment using Corvis ST between January 2017 and December 2021 were enrolled. Subjects with central corneal thickness (CCT) <500 μ, intraocular pressure (IOP) >21 mmHg, history of any systemic and ocular disease or any previous ocular surgery, high astigmatism, corneal disease such as keratoconus were excluded. Subjects with missing data or having poor quality scan were excluded. Corneal biomechanical properties and corneal SSI were assessed using Corvis ST. For statistical purposes, eyes were divided into four different groups and were analyzed using one-way ANOVA. Nine hundred and sixty-six myopic eyes with mean ± standard deviation age, IOP, and CCT of 26.89 ± 4.92 years, 16.94 ± 2.00 mmHg, and 540.18 ± 25.23 microns, respectively, were included. There were 311, 388, 172, and 95 eyes that were low, moderate, severe, and extreme myopic. Deformation amplitude ratio at 1 mm and 2 mm were similar across different myopic groups. A significant increase in max inverse radius, ambrosia relational thickness, biomechanically corrected IOP, integrated radius was noted with an increase in myopic refractive error. Corvis biomechanical index, corneal SSI was found to be decreased significantly with an increase in myopic refractive error. We noted a significant positive association between myopic refractive error and SSI (P < 0.001). Corneal SSI was found to be reduced in extreme myopic eyes.

Pupillary Diameter Change and Dynamics in Different Refractive Error Groups after Implantation of a Collamer Lens with a Central Hole Without Viscoelastic Agent

Background: To investigate the pupillary diameter and dynamics in different refractive error groups after non-viscoelastic agent-assisted implantation of a collamer lens with a central hole, so as to evaluate the effect on the pupil of this type of surgery. Methods: Consecutive patients with a range of refractive errors who underwent non-viscoelastic agent-assisted implantation of a collamer lens with a central hole (ICL V4c) were analyzed. OPD-Scan III (NIDEK Japan)was used to measure the pupillary diameter preoperatively and 1 month postoperatively. Pupillary dynamics were assessed by calculating the scotopic pupillary diameter minus the photopic pupillary diameter. All variables were measured under photopic and scotopic conditions. Results: In 53 patients (medium-low myopia group 44 eyes, 23 patients, age 33.3±1.2 years and high myopia group 60 eyes, 30 patients, age 31.7±1.5 years), the postoperative photopic pupil was significantly smaller than preoperatively in both groups, and the postoperative pupillary size was significantly larger in the high myopia group under both the photopic and scotopic conditions. Besides, the high myopia group had a significantly larger photopic-scotopic change postoperatively and greater change in the pupillary dynamics. Conclusion: Implantation of a collamer lens with a central hole without viscoelastic agent assistance affected the pupillary diameter and dynamics at 1 month postoperatively in the medium-low and high myopia groups. The group with medium and low diopters had stronger changes in pupil diameter after surgery, while the group with high diopters was more likely to be affected by changes in visual quality.

OUTCOME COMPARISON OF LASER-ASSISTED IN SITU KERATOMILEUSIS IN VARIOUS DEGREE OF MYOPIA

Introduction: The femtosecond Laser-Assisted in Situ Keratomileusis (fs-LASIK) procedure is commonly used for myopia correction because of good efficacy, safety, and predictability. The aim of this study was to compare the outcome of the fs-LASIK procedure among myopia groups in Cicendo Eye Hospital from January to December 2021. Methods: This retrospective study included 212 patients (399 eyes) and the data were obtained from medical records from January 2021 to December 2021 using ICD-10 coding for LASIK (S0800), consisting of fs-LASIK procedures. The outcome variables were safety index, and efficacy index. Results: The median of safety index was not statistically significant different between groups, 1,00(0,50-1,67) in low myopia, 1,00(0,20-1,43) in moderate myopia, and 1,00(0,30-3,33) in high myopia. The median of efficacy index was statistically significant different between groups, 1,00(0,40-1,67) in low myopia, 1,00(0,20-1,43) in moderate myopia, and 1,00(0,30-3,33) in high myopia. The proportion of eye with UCVA &gt; 6/12 on the first month after the procedure was higher in the mild myopia group (223;99,2%) than in moderate myopia (87;98,8%) and high myopia (77;88,5%) with p=0,0001. The proportion of eye with BCVA &gt; 6/12 on the first month after the procedure was also higher in the mild myopia group (224;100%) than in moderate myopia (87;98,8%) and high myopia (82;94,3%) with p=0,0001. Conclusion: There was no statistically significant difference of the safety index between groups. The efficacy index was statistically significant different between groups.

Observation of peripheral refraction in myopic anisometropia in young adults.

To investigate the differences in retinal refraction difference values (RDVs) of adult patients with myopic anisometropia compared with those without myopic anisometropia, and to investigate the relationship between ocular biometric measurements and relative peripheral refraction. This clinical observation study included 130 patients with myopia (-0.25 to -10.00 D) between October 2022 and January 2023 aged between 18 and 40y. The patients were divided into anisometropia (n=63; difference in binocular anisometropia ≥1.00 D) and non-anisometropia (n=67; difference in binocular anisometropia <1.00 D) groups accordingly. Ocular biometric measurements were performed by optical biometrics and corneal topography to assess the steep keratometry (Ks), flap keratometry (Kf), axial length (AL), corneal astigmatism (CYL; Ks-Kf), surface regularity index (SRI), surface asymmetry index (SAI), and central corneal thickness (CCT). The RDV was measured at five retinal areas from the fovea to 53 degrees (RDV-0-10, RDV-10-20, RDV-20-30, RDV-30-40, and RDV-40-53), the total RDV (TRDV) of 53 degrees, and four regions, including RDV-superior, RDV-inferior, RDV-temporal, and RDV-nasal. An analysis of Spearman correlation was carried out to examine the correlation between RDV and the spherical equivalent (SE) and ocular biological parameters. Within RDV-20-53, both groups showed relative hyperopic defocus, and the increase in RDV corresponds to the increase in eccentricity. In the myopic anisometropia group, the TRDV, RDV-20-53, RDV-superior, and more myopic eyes had significantly higher RDV-temporal values than less myopic eyes. (P<0.05). In the non-anisometropia group, there was no significant difference in the RDV between the more and less myopic eyes at different eccentricities (P>0.05). There was a negative correlation between SE and TRDV (r=-0.205, P=0.001), RDV-20-53 (r=-0.281, -0.183, -0.176, P<0.05), RDV-superior (r=-0.251, P<0.001), and RDV-temporal (r=-0.230, P<0.001), a negative correlation between CYL and RDV-10-30 (r=-0.147, -0.180, P<0.05), and a negative correlation between SRI and RDV-0-20 (r=-0.190, -0.170, P<0.05). AL had a positive correlation with RDV-20-30 (r=0.164, P=0.008) and RDV-temporal (r=0.160, P=0.010). More myopic eyes in patients with myopic anisometropia show more peripheral hyperopic defocus. Diopter and corneal morphology may affect peripheral retinal defocus.

Peripapillary intrachoroidal cavitation at the crossroads of peripapillary myopic changes.

To analyze the prevalence of peripapillary intra-choroidal cavitation (PICC) in eyes with gamma peripapillary atrophy (γPPA), in eyes with peripapillary staphyloma (PPS) and in those combining γPPA and PPS and to analyze border tissue discontinuity in PICC. This prospective cross-sectional non interventional study included highly myopic eyes. Non-highly myopic eyes were used as control. Radial and linear scans centered on the optic nerve head were performed using spectral-domain optical coherence tomography. Variables were analyzed along the twelve hourly optical coherence tomography sections in both eyes of each subject. A total of 667 eyes of 334 subjects were included: 229 (34.3%) highly myopic eyes and 438 (65.7%) non highly myopic eyes. The mean age of the highly myopic group was 48.99±17.81y. PICC was found in a total of 40 eyes and in 13.2% (29/220) of highly myopic eyes. PICC was found in 10.4% (40/386) of eyes with γPPA, in 20.5% (40/195) of eyes with PPS and in 22.7% (40/176) of those combining γPPA and PPS. All the eyes with PICC showed the co-existence of γPPA and PPS whereas none of the eyes presenting only one of these entities exhibited PICC. A border tissue discontinuity in the γPPA area was found in all eyes with PICC. We confirm the presence of a border tissue discontinuity in the γPPA area of all eyes with PICC. These findings suggest the involvement of mechanical factors in the pathogenesis of PICC which may contribute to PICC-related visual field defects.

Trajectories of spherical equivalent refraction from grades 1 to 4 in Chinese children

BackgroundThe development trajectories of children’s SER remain unknown. This study aimed to characterize spherical equivalent refraction (SER) trajectories during grades 1–4 in Chinese children.MethodsThis prospective cohort study included 1226 first-grade non-myopic children from 12 public primary schools, randomly selected in two districts in Guangzhou, China. From November 2018 to March 2022, four-wave ocular examinations and questionnaire surveys have been completed. The group-based trajectory modeling was used to explore SER trajectories in grades 1–4.ResultsAll five trajectories showed an upward trend and rose faster after grade 2. Children in the sharp-developing (n = 44), high-developing (n = 136), and rapid-developing (n = 237) myopia groups developed myopia before grades 2, 3, and 4, respectively. Their SER development speed remained at a relatively high level after myopia, almost consistent with that before myopia. Children in the moderate-developing (n = 418) and low-developing (n = 391) non-myopia groups did not develop myopia before grade 4. Some characteristics in grade 1 were independently associated with SER trajectories, including sex, axial length, number of parents with myopia, residence, academic achievement, and the duration of outdoor activity. Based on the baseline characteristics, we established the model predicting the probability of children belonging to each group.ConclusionsMyopia interventions are best started in grade 1 or preschool age. If interventions are not taken in time, the latest intervention window might be in grades 1, 2, and 3 for children with a high probability of belonging to the sharp-developing, high-developing, and rapid-developing myopia groups, respectively. The above probabilities might be predicted using the model we established. Moreover, the interventions for myopic children shouldn’t be ignored.

Assessment of changes in macular structural retinal layers in patients with pathological myopia.

This study aimed to examine changes in the thickness of individual macular retinal layers in eyes with pathological myopia (PM) and to compare the thickness of each retinal layer between the PM and control groups to gain insights into retinal perfusion. The study included 51 eyes in the PM group and 51 eyes in the control group. Optical coherence tomography (OCT) was used to measure the thickness of each retinal layer in the central fovea, parafoveal, and perifoveal regions. Optical coherence tomography angiography (OCT-A) was used to evaluate the retinal capillary density. In the PM group, the retinal nerve fiber layer (RNFL), ganglion cell layer (GCL), inner plexiform layer (IPL), and inner nuclear layer (INL) were thicker than in the control group (p = 0.004, p = 0.027, p = 0.020, and p < 0.001, respectively), whereas the outer nuclear layer (ONL) and photoreceptor layer (PRL) were thinner (p = 0.001 and p = 0.003, respectively). In other regions, the RNFL was thicker in the myopic group, whereas the GCL, IPL, INL, and ONL were thinner. OCT-A did not reveal any significant difference between the groups in terms of radial capillary plexus density (p = 0.381); however, the densities of the other plexuses were lower in the PM group. The results showed alterations in the thickness of retinal layers and capillary plexus density in PM. Thus, assessment of the thickness of individual retinal layers may serve as an indicator of vascular diseases that affect the circulation of the retina and choroid.

Morphology and thickness of corneal endothelial cells in young Sudanese individuals with myopia.

Deviations in corneal endothelium morphology and thickness may indicate corneal abnormalities and could be associated with myopia development. This study aimed to evaluate corneal endothelial cell morphology and central corneal thickness in young individuals with myopia. A prospective study was conducted at Al-Neelain University Eye Hospital between January 2019 and January 2020, including 160 patients with myopia (320 eyes). Data was gathered through clinical assessment of visual acuity, refractive error, and corneal endothelial cells. Results showed that 60% of participants with myopia were female, with a mean age of 21.99±2.8 years and a mean equivalent sphere of -3.19±2.67D. There was a significant difference in endothelial cell degeneration between myopia groups (P<0.001). Corneal guttata occurred in 9.1% of eyes with low myopia and 68.2% with moderate myopia, whereas polymegathism and polymorphism were more prevalent in high myopia. The mean central corneal thickness was 500.50±38.94 µm in low myopia, 497.02±36.23 µm in moderate myopia, and 477.87±43.625 µm in high myopia (P=0.007). The mean endothelial cell number in low myopia was 107.86±21.12, 106.0±24.03 in moderate myopia, and 101.23±18.49 in high myopia (P<0.05). The mean difference in endothelial cell density, coefficient of variation, and hexagonality in low, moderate, and high myopia was not significant (P>0.05). However, Pearson's correlation revealed a significant negative correlation between the degree of myopia and central corneal thickness (r= -0.174, P=0.002) as well as endothelial cell number (r= -0.124, P=0.026). The study concluded that central corneal thickness and endothelial cell number significantly decreased with an increase in the degree of myopia. Corneal guttata was the most common form of endothelial cell degeneration observed in cases of high myopia.

Age-Related Changes in Total Corneal Astigmatism in Eyes With High Myopia.

The purpose of this study was to compare age-related changes in corneal astigmatism in eyes with and without high myopia. Eight-hundred eyes with high myopia (axial length ≥26.0 mm) and 800 eyes without high myopia (200 eyes each from patients in their 40s, 50s, 60s, and ≥70s) underwent videokeratographic examination. The amounts of vertical/horizontal (Rx) and oblique astigmatism (Ry) components, irregular astigmatism, and corneal shape were compared between eyes with and without high myopia and among age categories. In both groups, the mean Rx significantly changed to more positive with age ( P < 0.001), whereas the Ry did not change significantly. The Rx was significantly more negative in the high myopia group than in the control group in all age categories ( P ≤ 0.003), whereas the Ry did not differ significantly. The mean changes in the Rx and Ry during each 2 consecutive decades did not differ significantly between groups. The asymmetry and higher-order irregularity components increased with age ( P ≤ 0.001) but did not differ significantly between groups, except for the higher-order irregularity in patients in their 60s ( P = 0.018). In the averaged map, the corneal shape changed from with-the-rule to against-the-rule astigmatism with age in both groups, but the changes occurred later in the high myopia group. Age-related changes from with-the-rule to against-the-rule astigmatism occurred later in eyes with high myopia compared with eyes without high myopia in middle or older aged patients, but this change in each age decade was comparable between eyes with and without high myopia.

Changes in choroidal hemodynamics of form-deprivation myopia in Guinea pigs

PurposeWe studied changes in the choroid, particularly variation in blood flow, during the development of myopia. The hemodynamic mechanism in play remains unclear. We evaluated blood flow by quantitating indocyanine green (ICG) fluorescence in a guinea pig model of form-deprivation myopia. MethodsGuinea pigs were divided into form-deprivation myopia (FDM) and normal control (NC) groups. Ocular biometric and choroidal hemodynamics parameters were quantitatively derived via ICG imaging, and included the maximal ICG fluorescence intensity (Imax), rising time (Trising), blood flow index (BFI), and mean transit time (MTT). ResultsForm deprivation was associated with significant interocular differences in terms of both refractive error and axial length. ICG fluorescence hemodynamic maps of fundal blood flow and vasculature density were evident. In deprived eyes, the fluorescence signals exhibited significantly longer Trising and MTT but lower Imax and BFI than fellow eyes and NC group. The interocular differences in terms of the ocular biometric and hemodynamic parameters were significantly correlated. Hemodynamic analysis of choriocapillaris lobules revealed weakened fluorescence intensity and prolonged arrival and filling times in deprived eyes. Form deprivation reduced the number of lobulated choriocapillaris structures. ConclusionForm-deprivation myopia triggered changes in the hemodynamic and vascular network structures of the choroid and choriocapillaris. The ICG fluorescence imaging/analysis method provides a unique tool for further myopia research.

Comparison of the new self-contained darkroom refractive screener versus table-top autorefractor and cycloplegia retinoscopy in detecting refractive error

PurposeBy comparing the results of the new self-contained darkroom refractive screener (YD-SX-A) versus table-top autorefractor and cycloplegic retinoscopy, to evaluate the performance of the YD-SX-A in detecting refractive error in children and adolescents and then judge whether it can be used in refractive screening.MethodsCross-sectional study. 1000 participants between the ages of 6 and 18 who visited the Optometry Center of the People's Hospital of Guangxi Zhuang Autonomous Region from June to December 2022 were selected. First, participants were instructed to measure their diopter with a table-top autorefractor (Topcon KR8800) and YD-SX-A in a noncycloplegic setting. After cycloplegia, they were retinoscopy by a professional optometrist. The results measured by three methods were collected respectively. To avoid deviation, only the right eye (1000 eyes) data were used in the statistical analysis. The Bland–Altman plots were used to evaluate the agreement of diopters measured by the three methods. The receiver operating characteristic (ROC) curves was used to analysis effectiveness of detecting refractive error of YD-SX-A.ResultsThe average age of participants was 10.77 ± 3.00 years, including 504 boys (50.4%) and 496 girls (49.6%). When YD-SX-A and cycloplegia retinoscopy (CR) were compared in the myopia group, there was no statistical difference in spherical equivalent (SE) (P > 0.05), but there was a statistical difference in diopter spherical (DS) and diopter cylinder (DC) (P < 0.05). Comparing the diopter results of Topcon KR8800 and CR, the difference between each test value in the myopia group was statistically significant (P < 0.05). In the hyperopia group, the comparison between YD-SX-A and CR showed no statistically significant differences in the DC (P > 0.05), but there were significant differences in the SE and DS (P < 0.05). In the astigmatism group, the SE, DS, and DC were statistically different, and the DC of YD-SX-A was lower than that of CR and Topcon KR8800. Bland–Altman plots indicated that YD-SX-A has a moderate agreement with CR and Topcon KR8800. The sensitivity and specificity of YD-SX-A for detecting myopia, hyperopia and astigmatism were 90.17% and 90.32%, 97.78% and 87.88%, 84.08% and 74.26%, respectively.ConclusionThis study has identified that YD-SX-A has shown good performance in both agreement and effectiveness in detecting refractive error when compared with Topcon KR8800 and CR. YD-SX-A could be a useful tool for large-scale population refractive screening.

Initial screening for occult congenital ectopia lentis based on ocular biological parameters in preschool children

BackgroundThis study aimed to identify an initial screening tool for congenital ectopia lentis (CEL) by comparing ocular biological parameters in children with myopia.MethodsA retrospective case-control study was conducted at one tertiary referral centre, from October 2020 to June 2022. Axial length (AL), corneal curvature (CC), refractive astigmatism (RA), corneal astigmatism (CA), internal astigmatism (IA), the difference between the axis of RA and CA [AXIS(RA-CA)], white-to-white corneal diameter (WTW), and axial length-corneal radius ratio (AL/CR) were compared in 28 eyes of CEL patients, and 60 eyes of myopic patients matched for age and refraction. The spherical equivalent of each eye was < -3.00 D. Area under the curve (AUC) of the receiver operating characteristic curves were calculated.ResultsThe differences in RA, AL, mean keratometry (Kmed), maximum keratometry (Kmax), minimum keratometry (Kmin), CA, IA, AXIS(RA-CA), WTW, and AL/CR between the CEL and myopic groups were statistically significant (p < 0.05; p < 0.001; p < 0.001; p < 0.001; p < 0.001; p < 0.05; p < 0.001; p < 0.001; p < 0.001; p < 0.001, respectively). In logistic regression analysis RA, IA, AXIS(RA-CA), and AL/CR were significantly associated with CEL (p < 0.05). AUCs for RA, IA, AXIS(RA-CA), and AL/CR were 0.694, 0.853, 0.814, and 0.960, respectively. AUCs for AL/CR in SE< -6.00 D subgroup was 0.970, and 0.990 in -6.00 D ≤ SE < -3.00 D group. An AL/CR < 3.024 was the optimal cut-off point differentiating the CEL and control groups (sensitivity, 92.9%; specificity, 88.30%).ConclusionsA smaller AL/CR could identify CEL in children with myopia. An AL/CR cut-off value of 3.024 may be the most sensitive and specific parameter for the differential diagnosis of CEL in patients with mild to high myopia.

Determination of depression, anxiety, and hopelessness levels in adolescents with refractive errors after the COVID-19 pandemic

Background/Aim: The prevalence of myopia is increasing worldwide especially among adolescents. Changes in living conditions such as reduced engagement in outdoor activities as well as increased activities near the workplace like reading, writing, and screen exposure are thought to be responsible for this increase. Adolescence is a sensitive period of rapid changes in psychological, physiological, and social aspects. Mental health issues such as anxiety and depression are common during this period. During the pandemic, mental health issues among children and adolescents increased due to stress caused by the disease, social isolation, disruption of routines, and the loss of loved ones. With the rapid increase in myopia among adolescents, there is a need to investigate the effects of myopia on mental health. The aim of this study is to evaluate anxiety, depression, and hopelessness levels in adolescents with myopia after the COVID-19 pandemic and to examine the relationship between myopia and anxiety, depression, and hopelessness. Methods: This was a case-control study that included 40 myopic adolescents aged 16-19 with a spherical refractive degree of -2 diopters (D) and above and 40 emmetropic (no refractive error). Participants who had previously undergone refractive surgery, had binocular visual acuity less than 1.0, had strabismus and amblyopia, had a diagnosis of glaucoma, had undergone ocular surgery for any reason, had retinopathy, or had an astigmatic refractive degree greater than ±0.50 were excluded from the study. The study did not include patients with chronic physiological or psychiatric diseases. Both groups were administered the Automatic Thoughts Questionnaire (ATQ), Coronavirus Anxiety Scale (CAS), Beck Hopelessness Scale (BHS), and Beck Depression Inventory (BDI). The groups were compared according to the scales. Myopic degrees were compared with mixed-effect linear models according to scale categories, and the relationship between ATS scores and myopia degrees was evaluated using the Spearman correlation coefficient. Results: The mean (SD) spherical refractive power of myopic adolescents was -3.156 (1.40) diopters; 62.5% of participants with myopia had been exposed to COVID-19, and the anxiety rate in myopic participants compared to controls was 15% (P=0.026). However, no significant difference was found between the myopia and control groups in terms of automatic thoughts, hopelessness, and depression inventory scores when comparing the groups. No correlation was found between the CAS (F=1.098), BHS (F=1.610), BDI (F=1.699), and ATQ (r=0.151) scales and the increase in myopia when we performed linear mixed model analysis and Spearman correlation analysis. There was no significant relationship between the degree of myopia and automatic thoughts, hopelessness anxiety, and depression. Conclusion: The results indicate that adolescents with myopia had higher levels of anxiety after the COVID-19 pandemic. There was no significant correlation between the degree of myopia and anxiety, depression, hopelessness, and automatic thoughts. It is important to monitor adolescents with myopia carefully during pandemics and provide the necessary mental health support. This is because offering mental health support to myopic young people may protect them from potential lasting emotional problems in adulthood during potential future pandemics. It may be beneficial for adolescents to increase their engagement in outdoor activities to reduce myopia and anxiety.

Correlation between refractive errors and ocular biometric parameters in children and adolescents: a systematic review and meta-analysis

BackgroundRefractive errors are one of the most common ocular conditions among children and adolescents, with myopia showing an increasing prevalence and early onset in this population. Recent studies have identified a correlation between refractive errors and ocular biometric parameters.MethodsA systematic search was conducted in electronic databases including PubMed, EMBASE, Cochrane Library, Web of Science, and Medline from January 1, 2012, to May 1, 2023. Various ocular biometric parameters were summarized under different refractive states, including axial length (AL), central corneal thickness (CCT), anterior chamber depth (ACD), lens thickness (LT), corneal curvature (CC), Corneal curvature radius (CR),axial length-to-corneal radius ratio (AL/CR ratio), choroidal thickness (ChT), retinal thickness (RT), retinal nerve fiber layer thickness (RNFL), and retinal blood density (VD). The differences in these parameters among different refractive states were analyzed using Stata software with fixed or random-effects models, taking into account the assessed heterogeneity level.ResultsThis meta-analysis included a total of 69 studies involving 128,178 eyes, including 48,795 emmetropic eyes, 60,691 myopic eyes, 13,983 hyperopic eyes, 2,040 low myopic eyes, 1,201 moderate myopic eyes, and 1,468 high myopic eyes. The results of our study demonstrated that, compared to the control group (emmetropic group), the myopic group and low, moderate, and high myopic groups showed significant increases in AL, AL/CR ratio, and ACD, while the hyperopic group exhibited significant decreases. Compared to the control group, the myopic group had a significantly increase for CC, while CR, CCT, perifoveal RT, subfoveal ChT, foveal ChT, parafoveal ChT, perifoveal (except nasal) ChT, and pRNFL (except temporal) significantly decreased. Compared to the control group, the hyperopic group had a significantly increase for subfoveal ChT, foveal ChT, parafoveal ChT, perifoveal ChT, and nasal pRNFL. Compared to the control group, the low and moderate myopic groups had a significantly decreases for the CCT, parafoveal RT (except nasal), perifoveal RT (except nasal), and pRNFL (except superior and temporal). Compared to the control group, the high myopic group had a significantly increase for CR, while LT, perifoveal ChT (except nasal), parafoveal RT, perifoveal RT, and pRNFL (except temporal) had significant decreased.ConclusionThe changes of ocular biometric parameters in children and adolescents are closely related to refractive errors. Ocular biometric parameters devices, as effective non-invasive techniques, provide objective biological markers for monitoring refractive errors such as myopia.

Myopia & painful muscle form of temporomandibular disorders: connections between vision, masticatory and cervical muscles activity and sensitivity and sleep quality

The main aim of this study is to evaluate the effects of painful muscle form of temporomandibular disorders and myopia on the connections between the visual organ, the bioelectrical activity and sensitivity of the masticatory and cervical muscles, and sleep quality. Subjects were divided into 4 groups (Myopia & TMDs, Myopia (Without TMDs), Emmetropic & TMDs and Emmetropic (Without TMDs)). The study was conducted in the following order of assessment: examination for temporomandibular disorders, assessment of the muscle activity by electromyograph, pressure pain thresholds examination, ophthalmic examination and completion of the Pittsburgh Sleep Quality Index. It was observed that the Myopia & TMDs group had higher muscle tenderness, higher resting and lower functional muscle bioelectrical activity. The visual organ is clinical related to the masticatory and cervical muscles. TMDs and myopia alter masticatory and cervical muscle activity. The thickness of the choroid in people with myopia is related to muscle tenderness. TMDs and myopia impair sleep quality. It is recommended to determine the number of people with refractive error and its magnitude in the sEMG study in order to be able to replicate the research methodology.

Quantitative analysis of optic disc changes in school-age children with ametropia based on artificial intelligence.

To explore changes in the optic disc and peripapillary atrophy (PPA) in school-age children with ametropia using color fundus photography combined with artificial intelligence (AI) technology. Based on the retrospective case-controlled study, 226 eyes of 113 children aged aged 6-12y were enrolled from October 2021 to May 2022. According to the results of spherical equivalent (SE), the children were divided into four groups: low myopia group (66 eyes), moderate myopia group (60 eyes), high myopia group (50 eyes) and emmetropia control group (50 eyes). All subjects underwent un-aided visual acuity, dilated pupil optometry, best-corrected visual acuity (BCVA), intraocular pressure, ocular axis measurement and color fundus photography. The width of PPA, horizontal diameter ratio of PPA to the optic disc and area ratio of PPA to the optic disc were significantly different among the four groups (P<0.05). The width of the nasal and temporal neuroretinal rim, the roundness of the optic disc, the height of PPA, the vertical diameter ratio of PPA to the optic disc, and the average density of PPA in the high myopia group were significantly different compared with the other three groups (P<0.05). There were strong negative correlations between SE and area ratio of PPA to the optic disc (r=-0.812, P<0.001) and strong positive correlation between axial length (AL) and area ratio of PPA to the optic disc (r=0.736, P<0.001). In school-age children with high myopia, the nasal and temporal neuroretinal rims are narrowed and even lost, which have high sensitivity. The area ratio of the PPA to the optic disc could be used as an early predictor of myopia progression, which is of great significance for the development prevention and management of myopia.

Exploration of the pathophysiology of high myopia via proteomic profiling of human corneal stromal lenticules

This study aimed to investigate the underlying pathophysiology of high myopia by analyzing the proteome of human corneal stromal lenticule samples obtained through small incision lenticule extraction (SMILE). A total of thirty-two patients who underwent SMILE were included in the study. Label-free quantitative proteomic analysis was performed on corneal stromal lenticule samples, equally representing high myopia (n = 10) and low myopia (n = 10) groups. The identified and profiled lenticule proteomes were analyzed using in silico tools to explore biological characteristics of differentially expressed proteins (DEPs). Additionally, LASSO regression and random forest model were employed to identify key proteins associated with the pathophysiology of high myopia. The DEPs were found to be closely linked to immune activation, extracellular matrix, and cell adhesion-related pathways according to gene ontology analysis. Specifically, decreased expression of COL1A1 and increased expression of CDH11 were associated with the pathogenesis of high myopia and validated by western blotting (n = 6) and quantitative real time polymerase chain reaction (n = 6). Overall, this study provides evidence that COL1A1 and CDH11 may contribute to the pathophysiology of high myopia based on comparative proteomic profiling of human corneal stromal lenticules obtained through SMILE.

Comparison of errors in ablation depth calculation after myopic femtosecond laser in situ keratomileusis in patients with different degrees of myopia: a prospective study

BackgroundTo investigate the difference between the predicted preoperative corneal ablation depth and the measured ablation depth for femtosecond laser in situ keratomileusis (FS-LASIK) in patients with different degrees of myopia, and to analyze the source of the difference.MethodsA total of 55 patients (109 eyes) were included in this study. Multiple logistics regression was applied to analyze the sources affecting postoperative refractive outcomes. The difference between the preoperative predicted corneal ablation depth and the 1-day postoperative ablation depth in patients with different degrees of myopia was explored using linear regression. Corneal biomechanical parameters influencing error in ablation depth calculation were examined using multiple linear regression.ResultsOne hundred and nine eyes were divided into low to moderate myopia (55 eyes, myopia of 6 D or less), high myopia (45 eyes, myopia ranging from 6 D to a maximum of 9 D), and very high myopia group (9 eyes, myopia greater than 9 D) based on preoperative refractive error (spherical equivalent). Postoperative visual outcomes were comparable among the three groups of patients, with no significant difference in uncorrected visual acuity (UCVA). We did find notable disparities in spherical equivalent (SE) and central corneal thickness (CCT) in patients with different degrees of myopia at 1 day postoperatively (all p < 0.001). Logistic regression analysis showed that error in ablation depth calculation was an independent risk factor for refractive outcomes one day after surgery (OR = 1.689, 95% CI: 1.366 – 2.089). There was a substantial discrepancy in error in ablation depth calculation at 1 day postoperatively between the three groups. The measured ablation depth of the laser platform was lower than the predicted ablation depth in the low to moderate myopia and very high myopia groups, but the opposite was true in the high myopia group. Pre-operative SE (p < 0.001) and corneal front minimum radius of curvature (Front Rmin) (p = 0.007) obviously influenced the error in ablation depth calculation.ConclusionsError in ablation depth calculation values vary significantly between patients with different degrees of myopia and correlate highly with preoperative SE and Front Rmin. At the same time, the available evidence suggests that error in ablation depth calculation is an influential factor in postoperative refractive status, so it is imperative to control error in ablation depth calculation.