Low Myopia Research Articles

Link between parental myopia and early-onset high myopia: Insights from a clinical retrospective analysis.

Genetic aetiology is suspected in the development of early-onset high myopia (spherical equivalent refractive error [SER] ≤-6.00 D at ≤6 years of age), considering that the role of environmental factors in inducing high myopia is improbable at an early age. Therefore, we aimed to understand if early-onset high myopia is associated with parental myopia in a clinical setting. A retrospective study was conducted in which information about demographics, age of apparent onset of myopia, refractive error, axial length, number of myopic parents, time spent outdoors and time spent on near-work was obtained from electronic medical records (EMR). It included 195 myopic individuals categorised into (1) Early-onset high myopes (EOHM): SER ≤ -6.00 D with age of presentation ≤6 years, (2) Early-onset low myopes (EOLM): SER > -6.00 D with age of apparent onset ≤6 years, (3) Late-onset high myopes (LOHM): SER ≤ -6.00 D with age of presentation and age of apparent onset >6 years and (4) Late-onset low myopes (LOLM): SER > -6.00 D with age of apparent onset >6 years. Overall, 63% of individuals were found to have parental myopia. The proportion of individuals with EOHM, EOLM, LOHM and LOLM with parental myopia was 57%, 74%, 53% and 64%, respectively. After adjustment for age, gender and environmental factors, the odds of development of EOHM (Odds ratio: 0.78, 95% confidence interval: 0.25-2.48), EOLM (1.54, 0.65-3.67) or LOHM (0.70, 0.30-1.65) were similar in the presence of myopic parents, when compared with LOLM. The SER and axial length did not differ based on the number of myopic parents in any of these categories. This retrospective analysis reveals that the presence of parental myopia, which was self-reported, did not induce additional risk for early-onset high myopia.

Clinical outcomes of topography-guided versus wavefront-optimized LASIK for correction of myopia and compound myopic astigmatism.

To compare the safety, efficacy, and visual outcomes of topography-guided (TG) LASIK ablation versus advanced ablation algorithm (AAA) on Zeiss Mel 90 on virgin eyes. A tertiary care hospital in north India. A retrospective comparative study. Case sheets of 30 patients who underwent TG LASIK and 45 patients who underwent AAA LASIK between January 2021 and September 2022 were retrieved and reviewed. The TG group included 60 eyes of 30 patients, and the AAA group included age- and sex-matched 90 eyes of 45 patients. Both groups were compared for visual outcomes, residual refraction, and root-mean-square higher-order aberrations (rms HOA) at 1 week, 1 month, 3 months, and 6 months postoperatively and using unpaired t-test and Mann-Whitney U test. The mean preoperative spherical equivalent in the TG group and AAA group was - 3.12 (1.67) and - 3.19 (1.61), respectively. The safety and efficacy of the treatment were 100% in both groups. The postoperative increase in rms HOA was comparable in both groups (P = 0.55). The ablation duration was significantly longer in topo-guided LASIK (P = 0.001). AAA LASIK on MEL 90 is comparable to topography-guided LASIK for the management of low myopia and myopic astigmatism.

Observation of structural and vascular features of retina and choroid in myopia using ultra-widefield SS-OCTA

BackgroundTo find the relationship between the changes of retinal and choriodal structure/ vascular densities (VD) and the myopia progress.Methods126 eyes of 126 age-matched young participants were divided into three groups: Emmetropia and Low Myopia (EaLM) (33 eyes), Moderate Myopia (MM) (39 eyes), and High Myopia (HM) (54 eyes). Fundus images measuring 12 × 12 mm were captured using ultra-widefield swept-source optical coherence tomography angiography (SS-OCTA). Each image was uniformly divided into nine regions: supra-temporal (ST), temporal (T), infra-temporal (IT), superior (S), central macular area (C), inferior (I), supra-nasal (SN), nasal (N), and infra-nasal (IN). Various structural parameters, including inner retina thickness (IRT), outer retina thickness (ORT), and choroid thickness (CT), were assessed, and the VD of the superficial capillary plexus (SCP), deep capillary plexus (DCP), choriocapillaries (CC), and choroid vessels (ChdV) were quantified.ResultsCT in upper fundus exhibited a significant reduction from EaLM to MM. Additionally, ORT (ST, S. SN, C, N, IT, I, IN), CT (ST, S, SN, T, C, N, IT, I, IN) and VDs of SCP (ST, S, C, I, IN), DCP (ST, S, T, C, I) and ChdV (T, N, I, IN) were statistically diminished in EaLM compared to HM. Furthermore, IRT (N), ORT (N, IN), CT (S, SN, T, C, IT, I) and VDs of SCP (I, IN) and DCP (I) exhibited significant decreases as MM progressed towards HM. Intriguingly, there was a notable increase in the VD of CC (ST, S, T, C, N) as myopia progressed from MM to HM.ConclusionSignificant changes in retinal and choroid structure and vascular density occur as moderate myopia advances to high myopia. Efforts to curb myopia progression to this stage are essential, as the failure to do so may lead to the development of corresponding retinopathy.

Glutathione and a Pool of Metabolites Partly Related to Oxidative Stress Are Associated with Low and High Myopia in an Altered Bioenergetic Environment.

Oxidative stress forms part of the molecular basis contributing to the development and manifestation of myopia, a refractive error with associated pathology that is increasingly prevalent worldwide and that subsequently leads to an upsurge in degenerative visual impairment due to conditions that are especially associated with high myopia. The purpose of our study was to examine the interrelation of potential oxidative-stress-related metabolites found in the aqueous humor of high-myopic, low-myopic, and non-myopic patients within a clinical study. We conducted a cross-sectional study, selecting two sets of patients undergoing cataract surgery. The first set, which was used to analyze metabolites through an NMR assay, comprised 116 patients. A total of 59 metabolites were assigned and quantified. The PLS-DA score plot clearly showed a separation with minimal overlap between the HM and control samples. The PLS-DA model allowed us to determine 31 major metabolite differences in the aqueous humor of the study groups. Complementary statistical analysis of the data allowed us to determine six metabolites that presented significant differences among the experimental groups (p < 005). A significant number of these metabolites were discovered to have a direct or indirect connection to oxidative stress linked with conditions of myopic eyes. Notably, we identified metabolites associated with bioenergetic pathways and metabolites that have undergone methylation, along with choline and its derivatives. The second set consisted of 73 patients who underwent a glutathione assay. Here, we showed significant variations in both reduced and oxidized glutathione in aqueous humor among all patient groups (p < 0.01) for the first time. Axial length, refractive status, and complete ophthalmologic examination were also recorded, and interrelations among metabolic and clinical parameters were evaluated.

Polygenic risk score-based phenome-wide association for glaucoma and its impact on disease susceptibility in two large biobanks

BackgroundGlaucoma is a leading cause of worldwide irreversible blindness. Considerable uncertainty remains regarding the association between a variety of phenotypes and the genetic risk of glaucoma, as well as the impact they exert on the glaucoma development.MethodsWe investigated the associations of genetic liability for primary open angle glaucoma (POAG) with a wide range of potential risk factors and to assess its impact on the risk of incident glaucoma. The phenome-wide association study (PheWAS) approach was applied to determine the association of POAG polygenic risk score (PRS) with a wide range of phenotypes in 377, 852 participants from the UK Biobank study and 43,623 participants from the Penn Medicine Biobank study, all of European ancestry. Participants were stratified into four risk tiers: low, intermediate, high, and very high-risk. Cox proportional hazard models assessed the relationship of POAG PRS and ocular factors with new glaucoma events.ResultsIn both discovery and replication set in the PheWAS, a higher genetic predisposition to POAG was specifically correlated with ocular disease phenotypes. The POAG PRS exhibited correlations with low corneal hysteresis, refractive error, and ocular hypertension, demonstrating a strong association with the onset of glaucoma. Individuals carrying a high genetic burden exhibited a 9.20-fold, 11.88-fold, and 28.85-fold increase in glaucoma incidence when associated with low corneal hysteresis, high myopia, and elevated intraocular pressure, respectively.ConclusionGenetic susceptibility to POAG primarily influences ocular conditions, with limited systemic associations. Notably, the baseline polygenic risk for POAG robustly associates with new glaucoma events, revealing a large combined effect of genetic and ocular risk factors on glaucoma incidents.

OBESITY IN CHILDREN AS A PREDICTOR OF THE DEVELOPMENT OF MYOPIA

Despite a suffi cient number of scientifi c studies devoted to the study of myopia risk factors, the infl uence of obesity on the degree of myopia risk in childhood has not been suffi ciently studied, which prompted us to study this issue using children as an example. The aim is to study the frequency and degree of myopia risk in overweight and obese children.Material and Methods. The sample of children for the study was formed step by step in the process of randomization. Thefi rst stage included a one-time epidemiological study of children aged 10-18 years during preventive examinations in schools of Chernivtsi and Chernivtsi region (1,035 persons). The primary screening included anthropometry and assessment of physical development. For detailed examination 205 persons were selected: with overweight (OW, 65 persons), with obesity (75 persons) and with normal body weight (65 persons, comparison group). The ophthalmologic examination included: visometry without and with correction, autorefractokeratometry before and after cycloplegia, biomicroscopy, ophthalmoscopy, optical biometry of the eye. To reveal the statistical diff erence between indicators in normally distributed groups, the Student’s t criterion of reliability was used, the degree of signifi cance – r. Comparison of groups on a qualitative basis was performed using Pearson’s χ2 test. Diff erences were considered statistically signifi cant at p &lt;0.05.The research design and all methods used in this study were reviewed and approved by the Bioethics Committee of theBukovinian State Medical University (Protocol No. 10, dated 18.05.2002). The study was conducted within the research work «Early diagnosis, treatment and prevention of combined pathology of gastrointestinal tract and thyroid gland in children» (state registration number 0116U002937, implementation period 02.2016-11.2022).Results. The frequency of myopia in children with OW and obesity was signifi cantly higher than in children with average body weight (χ2 = 3.2, p &lt; 0.05). Children with obesity and myopia were 2.7 times more likely to have diseases of the musculoskeletal system, 1.8 times more likely to have pathology of the autonomic nervous system, and 3.1 times more likely to have chronic diseases of the oropharynx than children in the control group. In all groups of children, the additional risk was greatest in children whose mother or father was myopic (49.6 and 41.3 %, respectively). Minimal additional risk was associated with a history of childhood infections (&lt;1.6 %), helminthiasis (&lt;3.9 %), nasal polyps (&lt;3.4 %), adenoids (&lt;2.4 %), and spinal cord injury at birth (&lt;9.1 %). The odds ratio for the development of low myopia in the group with OW and obesity compared to the control group (normal weight) were 1.25 [95 % CI 0.56-2.82] and 0.88 [95 % CI 0.49-1. 58], for the development of moderate myopia – 1.22 [95 % CI 0.57-2.59] and 0.82 [95 % CI 0.46-1.49], respectively, and for the development of high myopia–1.37 [95 % CI 0.51-3.66] and 0.80 [95 % CI 0.49-2.09], respectively.Conclusion. The risk of myopia is higher in children with overweight and obesity, which emphasizes the importance andnecessity of taking into account the somatic condition of the child.

Corneal biomechanics are not exclusively compromised in high myopia.

Research assuming linearity has concluded that corneal biomechanics are compromised in high myopia. We investigated whether this assumption was appropriate and re-examined these associations across different levels of myopia. Myopic (spherical equivalent refraction, SER ≤ -0.50 D) eyes of 10,488 adults aged 40-69 years without any history of systemic and ocular conditions were identified in the UK Biobank. Ordinary least squares (OLS) regression was employed to test the linear association between corneal hysteresis (CH) or corneal resistance factor (CRF), separately, and SER while controlling for age, sex, corneal radius and intraocular pressure. Quantile regression (QR) was used to test the same set of associations across 49 equally spaced conditional quantiles of SER. In OLS regression, each standard deviation (SD) decrease in CH and CRF was associated with 0.08 D (95% CI: 0.04-0.12; p < 0.001) and 0.10 D (95% CI: 0.04-0.15; p < 0.001) higher myopia, respectively. However, residual analysis indicated that the linearity assumption was violated. QR revealed no evidence of a significant association between CH/CRF and SER in low myopia, but a significant (p < 0.05) positive association became evident from -2.78 D (0.06 and 0.08 D higher myopia per SD decrease in CH and CRF). The magnitude of association increased exponentially with increasing myopia: in the -5.03 D quantile, every SD decrease in CH and CRF was associated with 0.17 D (95% CI: 0.08-0.25; p < 0.001) and 0.21 D (95% CI: 0.10-0.31; p < 0.001) higher myopia. In the -8.63 D quantile, this further increased to 0.54 D (95% CI: 0.33-0.76; p < 0.001) and 0.67 D (95% CI: 0.41-0.93; p < 0.001) higher myopia per SD decrease in CH and CRF. Corneal biomechanics appeared compromised from around -3.00 D. These changes were observed to be exponential with increasing myopia.

Prevalence of myopia in schoolchildren of a highly urbanized city in Eastern Siberia

Myopia is one of the most urgent problems of modern ophthalmology. Statistics show that the number of children and adolescents suffering from myopia is steadily increasing worldwide. But it also noted that in different regions of the Russian Federation, the proportion of children who are diagnosed with myopia may differ markedly. Purpose: to determine the prevalence and structure of myopia in schoolchildren of the city of Krasnoyarsk, depending on age and gender. Materials and methods. A survey of 3005 students of secondary schools in the city of Krasnoyarsk aged from 6 to 18 years, including 1,421 schoolboys and 1,584 schoolgirls, was conducted. Refraction was determined after cycloplegia using the autorefractometry method. Results. The predominant type of refraction in primary school students of both fi elds is emmetropia, myopia is in second place and other refractive errors are in third place. The prevalence of myopia in schoolchildren increases as they grow up. At the same time, in the schools of the city of Krasnoyarsk, already in the primary grades in the group of subjects of both sexes, the proportion of students with myopia was 17.9 %, in the middle – 36.8 %, and by the high classes it reached 49.7 %. When considering the data obtained, depending on gender, approximately the same proportions of myopia were found in primary grades in both schoolgirls (19.2 %) and schoolchildren (16.7 %), in middle grades, a statistically significant predominance of myopic refraction in girls, compared with boys (42.8 and 29.5 %, respectively, p &lt; 0.05). In high school, the proportion of myopia increases both in girls to 52.1 % and in boys to 47.2 %. The proportion of subjects with emmetropic refraction decreases as individuals of both sexes grow up. The percentage of other refractive errors remains without significant gender-age changes. Low myopia was the most common in all groups, but its percentage significantly decreased as they moved to higher grades, simultaneously with an increase in the proportion of moderate and high myopia. Conclusions. There is an increase in the prevalence of myopia in schoolchildren as they move to higher grades. A threefold increase in the proportion of myopia in high school compared with primary school was revealed. It is necessary to further study the prevalence of myopia in all Russian regions and develop preventive programs to control myopia in children.

Reduced contrast sensitivity function is correlated with changes to cone photoreceptors in simple high myopia.

To investigate the contrast sensitivity function (CSF) changes in simple high myopia (SHM) and evaluate the correlations between these changes with the early changes in the retinal microstructure. This prospective study comprised 81 subjects, 20 with emmetropia (EM), 26 with low myopia and moderate myopia (LM/MM), and 35 with SHM. The area under the log CSF curve (AULCSF) and the cut-off spatial frequency (Cut-off SF) were employed as measures of CSF. Adaptive optics (AO) was employed to quantify the cone density, spacing, and regularity. The thickness and blood flow of the retinal sublayers were determined from vertical and horizontal optical coherence tomography angiography (OCTA) A-scans. Swept-source optical coherence tomography (SS-OCT) was employed to analyze the choroidal thickness (CT) and choroidal vascularity using a custom algorithm. Differences in the retinal and choroidal parameters, cone distribution, AULCSF, and Cut-off SF were compared among the three groups. Multivariate linear mixed models were used to elucidate the associations between photoreceptor morphological alterations, retinal and choroidal parameters, and AULCSF. The AULCSF and Cut-off SF were significantly lower in the SHM group compared to the EM and LM groups (p < 0.05). The SHM group had less cone density, larger cone spacing, and lower cone regularity than the EM and LM/MM groups (p < 0.05). Moreover, the thickness of the inner segment of photoreceptors (IS), retinal pigment epithelium (RPE) layer and choroid were reduced, and the outer segment of photoreceptors (OS) was thicker in the SHM group compared to the EM and LM/MM groups (all p < 0.05). A longer axial length (AL) was correlated with decreased AULCSF, cone density, and cone spacing (r = -0.800 to 0.752, all p < 0.050). Additionally, decreased CSF was correlated with lower cone density (r = 0.338, p = 0.035). Decreased contrast sensitivity was observed in patients with SHM and cone density was significantly correlated with reduced AUCSF.

The first experience of parallel measurements of objective accommodation parameters in children with myopia using various instruments: in search of a common denominator

Purpose: to study the relationship between the parameters of reflex and tonic accommodation measured using various objective methods.Material and methods. A comprehensive parallel study of objective accommodation parameters of 57 children (114 eyes) with low and moderate myopia (average -2.6 ± 1.4 D) aged from 8 to 12 years (average 9.9 ± 1.6 years) was carried out on three devices: Grand Seiko WAM-5500K, Acomoref 2 K-model Righton; TONOREF III, Nidek.Results. Both coincidences and differences of the indicators obtained by different methods as well as their correlations were revealed: positive - between the values of AR in the open field and in the virtual space (r = 0.23, r = 0.2); between the virtual responses to Righton K-2 and Nidek (r = 0.38); direct correlations of the accommodation response with accommodation tones. A correlation of average strength (r = 0.44) was found between the HAT on the Grand Seiko WR-5100K and the CMF on the Righton K2, which allows us to consider them as synonymous indicators. A negative relationship of CMF with PRA and SE refraction was found. A positive correlation of CMF with the rate of progression of myopia and a negative one with PRA suggests that a high CMF is a bad prognostic sign. However, CMF positively correlates with the magnitude of the accommodative response on all three devices. In this case, it turns out that an increase in CMF accompanies an increase in the amplitude of accommodation and, therefore, is not always a troublesome factor. Perhaps we are dealing with the limits of the norm for this indicator, which still need to be studied.Conclusion. With the help of objective methods of studying qualitatively different characteristics of one process, it is possible to investigate the actual and prognostic parameters of accommodation, which will allow us to offer an individualized approach to the treatment of patients with myopia using optical and drug instruments.

Prevalence and Estimation of the Evolution of Myopia in Spanish Children.

Background: In recent decades, myopia has turned into a public health issue across the world. Between 1993 and 2016, the percentage of myopes increased from 10.4% to 34.2%. This study aims to analyze the myopia prevalence in Spanish children from five to seven years old over the last five years and to predict the rate of myopia in Spain by 2030. Methods: The sample consisted of children aged between 5 and 7, who underwent an optometric examination consisting of the measurement of visual acuity (VA) and determination of objective and subjective refraction. The cut-off points to define refractive error are established by the spherical equivalent (SE) value: hyperopia for an SE over or equal to +0.50 D; myopia for an SE under or equal to -0.50 D; and emmetropia when the SE is between -0.50 D and +0.50 D. Results: The myopia rate in Spanish children aged between five and seven was 19%. Myopia prevalence progressively increased as children grew up (p ≤ 0.001). It is estimated that, in the year 2030, the rate of myopia will be 30.2% [CI: 25.3-35.0], of which 81.9% [CI: 78.3-85.3] will have low myopia, 10.0% [CI: 7.2-12.8] moderate myopia, and 7.3% [CI: 4.9-9.7] high myopia. Conclusions: Nineteen percent of Spanish children between five and seven are myopes. In 2030, is expected that 30.2% of Spanish children between 5 and 7 years of age will be myopes. These estimations will support eye care professionals in recommending that children spend more time outdoors to prevent the onset of myopia and the use of methods to control myopia to avoid reaching these figures of high myopia.

Academic performance and musculoskeletal pain in adolescents with uncorrected vision problems

BackgroundUndetected vision problems are common in school children, and a prevalence of up to 40% has previously been reported. Uncorrected vision and lack of optimal eye wear can have a significant impact on almost all aspects of everyday life, such as development and learning, academic performance, pain and discomfort, and quality of life. This study aimed to analyze the relationship between uncorrected vision problems, educational outcomes, and musculoskeletal pain symptoms.MethodsA total of 152 school children (15.1 ± 0.8 years, mean ± SD; 40% males) were included in the study. All participants were recruited from a free-of-charge school vision testing program in Kathmandu, Nepal. Academic grades were collected from the school records of the participants’ nationwide final grade examinations. A questionnaire was used to record the use of digital devices, screen time, and associated symptoms, including musculoskeletal pain (Wong-Baker FACES Pain Rating Scales).ResultsA total of 61 children (40%) had uncorrected vision, with a cycloplegic refraction of SER − 0.53 ± 0.52 (mean ± SD). Children with uncorrected vision had significantly more third division grades (26 vs. 9%, p = 0.004) and shoulder pain in general/during screen use (66 vs. 43/40%, p = 0.008/0.003; 2.1/1.9 vs. 1.1/1.0 mean pain score, p = 0.002/0.001) compared with children with normal vision. Sex based subanalyses showed that only girls with uncorrected vision had more third division grades (25 vs. 4%, p = 0.006), and only boys with uncorrected vision had more shoulder pain in general/during screen use (76 vs. 28/31%, p < 0.001; 2.2/2.4 vs. 0.7 mean pain score, p < 0.001), compared with children with normal vision.ConclusionsThe results of this study showed that even small refractive errors may impact educational outcomes and musculoskeletal pain in adolescents. Most of the participating children had low myopia, easily corrected with glasses. This suggests that regular eye examinations are important in school children, and there is a need for raised awareness among parents, and school- and healthcare personnel.

Changes in posterior corneal elevation after small incision lenticule extraction for different myopic diopters.

To study the changes and effect factors of posterior corneal surface after small incision lenticule extraction (SMILE) with different myopic diopters. Ninety eyes of 90 patients who underwent SMILE were included in this retrospective study. Patients were allocated into three groups based on the preoperative spherical equivalent (SE): low myopia (SE≥-3.00 D), moderate myopia (-3.00 D>SE>-6.00 D) and high myopia (SE≤-6.00 D). Posterior corneal surfaces were measured by a Scheimpflug camera preoperatively and different postoperative times (1wk, 1, 3, 6mo, and 1y). Posterior mean elevation (PME) at 25 predetermined points of 3 concentric circles (2-, 4-, and 6-mm diameter) above the best fit sphere was analyzed. All surgeries were completed uneventfully and no ectasia was found through the observation. The difference of myopia group was significant at the 2-mm ring at 1 and 3mo postoperatively (1mo: P=0.017; 3mo: P=0.018). The effect of time on ΔPME was statistically significant (2-mm ring: P=0.001; 4-mm ring: P<0.001; 6-mm ring: P<0.001). The effect of different corneal locations on ΔPME was significant except 1wk postoperatively (1mo: P=0.000; 3mo: P=0.000; 6mo: P=0.001; 1y: P=0.001). Posterior corneal stability was linearly correlated with SE, central corneal thickness, ablation depth, residual bed thickness, percent ablation depth and percent stromal bed thickness. The posterior corneal surface changes dynamically after SMILE. No protrusion is observed on the posterior corneal surface in patients with different degrees of myopia within one year after surgery. SMILE has good stability, accuracy, safety and predictability.

Effect of Low Myopia on Near and Distance Vision in Astigmatic Pseudophakic Eyes

Purpose: To investigate the effect of the postoperative spherical equivalent (SE) and astigmatism on the uncorrected near/distance visual acuity (UNVA/UDVA) in monofocal intraocular lens (IOL)-implanted pseudophakic eyes.Methods: Of the eyes that underwent successful cataract surgery and monofocal IOL implantation from January 2020 to September 2021 by a single surgeon, eyes with postoperative astigmatism ≤ 1.5 diopters (D) and -0.75 D ≤ SE &lt; +0.25 D were included. Eyes implanted with a toric IOL or with a best corrected visual acuity under 20/25 were excluded. This was a cross-sectional study, and the correlation of SE/astigmatism and UNVA/UDVA at 1 month postoperatively was analyzed retrospectively. The eyes were divided into mini-myopia (-0.75 D ≤ SE &lt; -0.25 D) and emmetropia (-0.25 D ≤ SE &lt; 0.25 D) groups according to the SE.Results: This study included 118 eyes (86 patients). The UNVA was significantly better in the mini-myopia group than in the emmetropia group (&lt;i&gt;p&lt;/i&gt; = 0.009), without a significant difference in UDVA (&lt;i&gt;p&lt;/i&gt; = 0.412). Dividing the range into 0.5 D units according to the degree of astigmatism, no significant difference was observed in UNVA/UDVA between the mini-myopia and emmetropia groups in eyes with astigmatism ≤ 1.0 D. However, the mini-myopia group had a significantly better UNVA (&lt;i&gt;p&lt;/i&gt; = 0.03), without a significant difference in UDVA (&lt;i&gt;p&lt;/i&gt; = 0.879) in eyes with astigmatism &gt; 1.0 D or ≤ 1.5 D.Conclusions: In non-toric monofocal IOL-implanted pseudophakic eyes with postoperative residual astigmatism of ≤ 1.5 D, especially in eyes with astigmatism &gt; 1.0 D and ≤ 1.5 D, the mini-myopia group had a significantly better UNVA compared to the emmetropia group, without a significant difference in UDVA.

Quantitative Evaluation of the Topographical Maps of Three-Dimensional Choroidal Vascularity Index in Children With Different Degrees of Myopia.

To investigate topographical maps of the three-dimensional choroidal vascularity index (3D-CVI) in children with different levels of myopia. We enrolled 274 eyes from 143 children with various severity of myopia, including emmetropia (EM), low myopia (LM), and moderate-high myopia (MHM). The choroidal vessel volume (CVV), choroidal stroma volume (CSV), and 3D-CVI in different eccentricities (fovea, parafovea, and perifovea) and quadrants (nasal, temporal, superior, and inferior) were obtained from swept-source optical coherence tomography angiography (SS-OCTA) volume scans. All choroidal parameters were compared among groups, and the associated factors contributing to different 3D-CVIs were analyzed. Compared to the less myopic group, the more myopic group showed a significant decrease in CVV and CSV (MHM < LM < EM) and a significant increase in the 3D-CVI (MHM > LM > EM) in most areas (all P < 0.05). The nasal quadrant had the greatest 3D-CVI and lowest CSV and CVV, and vice versa in the temporal quadrant. The 3D-CVIs of the EM and LM groups gradually increased from the fovea to the perifovea, whereas the 3D-CVI of the MHM group first decreased and then increased. Regression analysis showed that axial length was an independent risk factor affecting foveal and parafoveal 3D-CVIs. Restricted cubic spline analysis revealed that the 3D-CVI increased with spherical equivalent (SE) when the SE was less than threshold and decreased when the SE was greater than threshold (SE thresholds for foveal, parafoveal, and perifoveal 3D-CVIs were -5.25 D, -5.125 D, and -2.00 D, respectively; all P < 0.05). Children with myopia exhibited decreased CSV and CVV, increased 3D-CVIs, and altered 3D-CVI eccentricity characteristics (from the fovea to the perifovea). The quadratic relationship between the 3D-CVI and SE should be explored in longitudinal investigations.

Comparison of the long-term effects of atropine in combination with Orthokeratology and defocus incorporated multiple segment lenses for myopia control in Chinese children and adolescents.

The aim of this study was to evaluate the efficacy of Orthokeratology (Ortho-K), defocus incorporated multiple segment (DIMS) lens, combined Ortho-K/atropine, and combined DIMS/atropine for myopia control in children. A retrospective study included 167 myopic children aged 6-14 years with a spherical equivalent refraction (SER) of -0.75 to -4.00 diopter treated with Ortho-K (OK, n = 41), combined Ortho-K/atropine (OKA, n = 43), DIMS (n = 41), or combined DIMS/atropine (DIMSA, n = 42). Axial length (AL) was measured at baseline and at 3, 6, 9 and 12 months. Axial elongation over time and between groups were analysed. After 12 months, the AL change was 0.20 ± 0.12 mm, 0.12 ± 0.14 mm, 0.22 ± 0.14 mm, and 0.15 ± 0.15 mm in the OK, OKA, DIMS, and DIMSA, respectively. There was no significant difference in AL change between OK and DIMS. OKA and DIMSA significantly slowed axial elongation compared to OK and DIMS monotherapy. After stratification by age, in the subgroup aged 6-10 years, there was significant difference in AL change between OKA and DIMS (p = 0.013), and no difference between other groups, while in the subgroup aged 10-14 years, the difference between OKA and DIMS became insignificant (p = 0.237), and the difference between OK and OKA, OK and DIMSA, DIMS and DIMSA became significant. Ortho-K and DIMS lenses show similar reductions in myopia progression among children with low initial myopia. Atropine can significantly improve the efficacy of myopia control of both Ortho-K and DIMS lenses, and this add-on effect is better in older children.

Refractive error and vision related quality of life

BackgroundTo investigate and compare the vision-related quality of life (QOL) in different types of refractive error (RE).MethodsThis cross-sectional study was performed on 200 subjects, categorized into four groups of 50 each, consisting of subjects with myopia, hyperopia, astigmatism, and emmetropia, the latter being the control group. The mean age of the participants was 23.88 ± 5.87 (range, 15 to 38: 110 females and 90 males). RE was defined as myopia, spherical equivalent (SE) < -0.25 diopters (D), hyperopia, SE > + 0.25 D, astigmatism, cylinder < -0.25 D, and emmetropia (-0.25 ≤ SE(D) ≤ + 0.25, cylinder ≥ -0.25). Groups are subdivided into very low magnitudes of RE (0.50 and 0.75) and significant RE (1.00 ≤). Vision-related QOL was assessed using the Persian version of the 25-item National Eye Institute Visual Functioning Questionnaire (NEI-VFQ-25). The NEI-VFQ was scored as visual function and socioemotional scales using Rasch analysis.ResultsCorrected myopia, astigmatism, uncorrected myopia, and hyperopia had a lower vision-related QOL than emmetropes. (P < 0.001). Vision-related QOL in myopic subjects was lower than that in astigmatic participants. Very low myopes, who often do not use correction, had a significantly lower QOL than other groups.ConclusionIndividuals with refractive errors experience a lower QOL score than those without. Notably, the adverse impact on QOL score is significantly greater in myopic cases, particularly very low myopia, compared to other refractive errors. Therefore, it is strongly recommended not to neglect managing very low myopia since it may improve participants’ QOL.

Refractive outcomes of small lenticule extraction (SMILE) Pro® with a 2 MHz femtosecond laser

PurposeTo evaluate the initial visual outcomes of Small Incision Lenticule Extraction (SMILE) Pro® using a 2 MHz femtosecond laser (VisuMax 800, Carl Zeiss Meditec) and to assess the efficacy, safety, predictability, accuracy, and complication rate.MethodsThis retrospective analysis included eyes which underwent the SMILE Pro® procedure using VisuMax 800 femtosecond laser to correct myopia. All surgeries were performed by one surgeon (DB). Follow-up was conducted 3 months postoperatively to evaluate visual outcomes after neuroadaptation, corrected visual acuity (CDVA) and intra- and postoperative complications.ResultsOne hundred and fifty-two eyes of 82 patients (mean age 31 ± 6 years) results at 3 months are presented. The mean spherical equivalent (SE) was − 4.44 ± 1.86 D preoperatively while -0.24 ± 0.32 D postoperatively. 99% of eyes achieved SE within ± 1.0 D of attempted correction and 91% were within ± 0.5 D. Efficacy index was 0.93 while the safety index was 1. No complications occurred intra- or postoperatively. No eyes lost more than 1 line of their preoperative CDVA. All highly myopic eyes (− 6.25 to − 10.00 D; n = 18) achieved 20/20 at 3 months postoperatively and were within 0.5 D from the attempted SE and no eyes lost more than 1 line of CDVA.ConclusionThe SMILE Pro® is a safe, efficient, and predictable procedure for the treatment of myopia and myopic astigmatism, with comparable results of conventional SMILE surgery. High myopic eyes achieve better results than low and moderate myopia. No complications were recorded in our patients.

Investigation and analysis of the status of myopia and related behavior in children and adolescents in Northeast Sichuan.

In this study, we examined the current status of myopia among primary and secondary school children in northeastern Sichuan to analyze the factors connected to myopia and provide data support and a theoretical foundation for the prevention and control of myopia. Using a cross-sectional study and a comprehensive sampling survey, 34,138 students aged 5-19 years were screened for refraction in 22 primary and secondary schools in Langzhong, and 4000 behavioral questionnaires were delivered at random. After evaluation and rational problem-solving, a total of 3764 valid questionnaires were obtained. SPSS 23.0 statistical software was used for data analysis. The percentage of myopia among primary and secondary school students in Langzhong was 65.61%, with female students having a higher rate than male students ( P < 0.05); 52.81% of primary school students, 86.26% of secondary school students, and 88.17% of high school students had myopia. The incidence of myopia detection increased with school age ( P < 0.001), indicating a correlation between age and myopia prevalence. The prevalence of myopia was mainly low (40.53%) and moderate myopia (19.89%). The prevalence of high myopia (5.19%) was relatively high. The prevalence of myopia among female students (5.54%) was greater than that in male students ( P < 0.05) and increased with age ( P < 0.001). The proportion of students who wore eyeglasses was 24.36%, with a larger proportion of female students (25.93%) than male students (22.61%) ( P < 0.001). In addition, the rate of eyeglass use increased with school age ( P < 0.001). A logistic regression analysis revealed that higher grade point averages, female gender, and long-term usage of electronic items were risk factors for myopia. The results of the questionnaire survey revealed that students in this region were under immense pressure to perform well academically, spent a lot of time engaged in near-work activities, and had a low rate of myopia awareness; 24.43% of the students had not had a vision examination in the previous year, indicating that parents did not pay sufficient attention to eye health. The incidence of myopia among children and teenagers is high in Northeast Sichuan, and the outlook for addressing the problem is bleak. Therefore, it is critical to improve vision monitoring and eye health education.

Association Between Peripheral Retinal Defocus and Myopia by Multispectral Refraction Topography in Chinese Children.

To investigate the association between the peripheral refractive errors of the fundus in different regions and moderate and high myopia. In this case-control study, 320 children and adolescents aged 6 to 18 years were recruited. Peripheral refractive errors were measured using multispectral retinal refractive topography (MRT). Spherical equivalent (SE) and cylinder errors were classified into low, moderate, and high categories based on the magnitude range. Logistic regression was performed to test the factors associated with myopia. There were 152 participants with low myopia and 168 participants with moderate and high myopia included in the current study. Participants with moderate and high myopia were most likely to be older, with larger axial length (AL), lower SE, less time to watch electronic devices on the weekend, a higher difference between central refractive error and paracentral refractive error from the superior side of the retina (RDV-S), but a smaller difference between the central refractive error and paracentral refractive error from the inferior side of the retina (RDV-I) than those with low myopia (all P <0.05). After logistic analysis, female sex (odds ratio [OR] = 4.14; 95% confidence interval [CI] = 2.16-7.97, P <0.001), AL (OR = 6.88, 95% CI = 4.33-10.93, P <0.001), and RDV-I (OR = 0.52, 95% CI = 0.32-0.86, P = 0.010) were independent factors for moderate and high myopia. Our study demonstrated that the retina peripheral refraction of the eyes (RDV-I) was associated with moderate and high myopia, and RDV-S was only associated with high myopia.