Cycloplegic refraction is the gold standard for epidemiological studies

Mean cycloplegic refractive error in emmetropic adults - The Tehran Eye Study

PURPOSE

In children under 20 years, refractive development targets a cycloplegic refractive error of +0.5 to +1.5D, while presbyopes over 40 years generally have non-cycloplegic errors of ≥ +1D. Some papers suggest these periods are separated by a period of myopic refractive error (i.e., ≤ -0.50D), but this remains unclear. Hence, this work investigates the mean cycloplegic refractive error in adults aged between 20 - 40 years.

METHODS

In 2002 a cross-sectional study with stratified cluster sampling was performed on the population of Tehran, providing cycloplegic and non-cycloplegic refractive error data for the right eyes of 3,576 participants, aged 30.6±18.6 years (range: 1-86 years). After grouping these data into age groups of 5 years, the refractive error histogram of each group was fitted to a Bigaussian function. The mean of the central, emmetropized peak was used to estimate the mean refractive error without the influence of myopia.

RESULTS

The mean cycloplegic refractive error at the emmetropized peak decreased from +1.10±0.11D (95 % confidence interval) to +0.50±0.04D before 20 years and remains stable at that value until the age of 50 years. The non-cycloplegic refractive error also sees a stable phase at 0.00±0.04D between 15 - 45 years. After 45 - 50 years both cycloplegic and non-cycloplegic refractive error become more hypermetropic over time, +1.14±0.12D at 75 years.

CONCLUSIONS

The cycloplegic refractive error in adults is about +0.50D between 20 - 50 years, disproving the existence of the myopic period at those ages.

The Performance of Spot Photoscreener in 6 to 10 Weeks Infants in China: A Cross-Sectional Study

Purpose

To compare the refractive errors measured by the Spot photoscreener (with or without cycloplegia) to cycloplegic retinoscopy in 6- to 10-week-old infants.

Materials and Methods

101 right eyes from 101 healthy infants aged 6 to 10 weeks were recruited for this cross-sectional observational study. Refractive errors were measured using Spot photoscreener before and after cycloplegia, as well as cycloplegic retinoscopy. Comparisons between the refractive measurements were performed using one-way ANOVA with the post hoc Tukey HSD test or Kruskal-Wallis test with the Steel-Dwass test according to the data normality. Pearson's correlation test and 95% confidence intervals were calculated. The agreement was evaluated using a Bland-Altman plot with 95% limits of agreement of the differences.

Results

Spot photoscreener was found to underestimate the spherical equivalent by 2.33 Diopters (D) in these infants. Following the induction of cycloplegia, the spherical equivalent measured by Spot photoscreener was in excellent agreement with cycloplegic retinoscopy with the mean difference of 0.01 D. Spot photoscreener overestimated cylindrical parameter by 0.2 D with poor agreement with cycloplegic retinoscopy no matter whether cycloplegia was induced. It had good agreement with cycloplegic retinoscopy in the J0 vector than the J45 vector measurement.

Conclusions

With the induction of cycloplegia, Spot photoscreener can accurately evaluate spherical equivalent in hyperopic infants with mild-to-moderate astigmatism. While it may provide valuable measurements of astigmatism, discrepancies in cylinder and axis should be taken into account.

Clinical Evaluation Of a 0.05 D-step Binocular Wavefront Optometer in Young Adults in China

CLINICAL RELEVANCE

Myopia has become a public health priority as its prevalence increases worldwide, and in clinical practice, the precise evaluation of refraction errors is necessary.

BACKGROUND

This study aimed to compare objective and subjective refraction measured by a binocular wavefront optometer (BWFOM) in adults with conventional objective and subjective refractions measured by an optometrist.

METHODS

This cross-sectional study included 119 eyes of 119 participants (34 men and 85 women; mean age:27.5 ± 6.3 years). Refractive errors were measured using BWFOM and conventional methods, with and without cycloplegia. The mean outcome measures were spherical power, cylindrical power, and spherical equivalence (SE). The agreement test was assessed using a two-tailed paired t-test and Bland - Altman plots.

RESULTS

Under noncycloplegic conditions, there were no significant differences in the objective SE between BWFOM and Nidek. Significant differences in subjective SE were observed between BWFOM and conventional subjective refraction (-5.79 ± 1.86 vs -5.65 ± 1.75 D, P < 0.01). Under cycloplegic conditions, the mean objective SE was significantly different between BWFOM and Nidek (-5.70 ± 1.76 vs -5.50 ± 1.83 D, P < 0.001); the mean subjective SE was significantly different between BWFOM and conventional subjective refractions (-5.52 ± 1.77 vs -5.62 ± 1.79 D, P < 0.001). The Bland - Altman plots revealed mean percentages of 95.38% and 95.17% for the points within the limits of agreement between BWFOM and conventional measurements and those between noncycloplegic and cycloplegic refractions, respectively.

CONCLUSION

The BWFOM is a new device that measures both objective and subjective refraction. It is more convenient and faster to obtain a proper prescription at a 0.05-D interval. The subjective refraction results of the BWFOM and the conventional subjective refraction were in good agreement.

Prevalence of refractive error in Nigerian children

Refractive errors can have profound effects on children. Cost and logistics prohibit national population-based studies and global data do not accurately reflect the burden among Nigerian children. This systematic review and meta-analysis aim to provide pooled prevalence and pattern of refractive error in Nigerian children. This review followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. The protocol for this study was pre-specified and registered on the International Prospective Register of Systematic Review (registration number ID: CRD42022303419). A systematic search of PubMed, EMBASE, Scopus, CINAHL Cochrane Library, African Journal Online, and African Index Medicus databases, was done for school-based, or population-based studies on refractive error prevalence in Nigerian children younger than 18 years of age or school children in pre-tertiary institutions. Quality-effect model was used to calculate weighted prevalence, odds ratio, and corresponding 95% confidence interval. Twenty-eight school-based studies including 34,866 children were identified. No population-based studies were found. The pooled prevalence of refractive error in Nigerian children was 5.9% (3.6-8.7%) and varied between regions and with the definition of refractive error used in the studies. The number of children needed to be screened to detect one case of refractive error was 15 (9-21). The odds of refractive error was higher in girls (odds ratio: 1.3 {1.1 to 1.5}), children >10 years (odds ratio: 1.7 {1.3 to 2.2}), and urban residents (odds ratio: 2.0 {1.6 to 2.5}). The high prevalence of refractive error in Nigerian children substantiates the value of screening school children for refractive error, particularly targeting urban and older children. Research is needed to refine case definitions and improve screening protocol. Population-based studies are needed to define the prevalence of refractive error in communities. The epidemiologic and methodological challenges in conducting prevalence reviews is discussed.

Predicting the onset of myopia in children by age, sex, and ethnicity: Results from the CLEERE Study

SIGNIFICANCE

Clinicians and researchers would benefit from being able to predict the onset of myopia for an individual child. This report provides a model for calculating the probability of myopia onset, year-by-year and cumulatively, based on results from the largest, most ethnically diverse study of myopia onset in the United States.

PURPOSE

This study aimed to model the probability of the onset of myopia in previously nonmyopic school-aged children.

METHODS

Children aged 6 years to less than 14 years of age at baseline participating in the Collaborative Longitudinal Evaluation of Ethnicity and Refractive Error (CLEERE) Study who were nonmyopic and less hyperopic than +3.00 D (spherical equivalent) were followed up for 1 to 7 years through eighth grade. Annual measurements included cycloplegic autorefraction, keratometry, ultrasound axial dimensions, and parental report of children's near work and time spent in outdoor and/or sports activities. The onset of myopia was defined as the first visit with at least -0.75 D of myopia in each principal meridian. The predictive model was built using discrete time survival analysis and evaluated with C statistics.

RESULTS

The model of the probability of the onset of myopia included cycloplegic spherical equivalent refractive error, the horizontal/vertical component of astigmatism (J0), age, sex, and race/ethnicity. Onset of myopia was more likely with lower amounts of hyperopia and less positive/more negative values of J0. Younger Asian American females had the highest eventual probability of onset, whereas older White males had the lowest. Model performance increased with older baseline age, with C statistics ranging from 0.83 at 6 years of age to 0.92 at 13 years.

CONCLUSIONS

The probability of the onset of myopia can be estimated for children in the major racial/ethnic groups within the United States on a year-by-year and cumulative basis up to age 14 years based on a simple set of refractive error and demographic variables.

The etiology, diagnostics, and treatment of the spasm of the near reflex - a narrative review

Physiological adaptation of the eye to the visual perception of near objects consists of the "near triad": convergence, accommodation, and pupil miosis. Normally, these tend to revert when one stops fixating on a near object. Spasm of the near reflex (SNR) is a pathological phenomenon, which manifests itself by the persistence of the above-mentioned adjustments, which prevents the eye from returning to its relaxed state. In this narrative review, we aim to summarize the etiology, diagnostics, treatment, and prevention of SNR. The literature review was performed by searching online databases. The clinical presentation of SNR is diverse; it presents as isolated accommodative spasm more frequently than impairment of all three components of the near triad. Patients usually present with fluctuations in visual acuity, blurred vision, diplopia, and asthenopia. The etiology is not fully understood. Potential causes include neuroanatomic, organic, and psychogenic disorders. The diagnosis is clinical, based on the constellation of symptoms and assessment of the near triad. The diagnostic golden standard is a cycloplegic examination of refraction, preferably using cyclopentolate hydrochloride (1%, 0.5%, or 0.1% solution). The first-line treatment requires the administration of a cycloplegic drug in combination with plus lenses, flipper lenses, optical fogging, or miotics. For secondary cases, causal treatment should be implemented. Prevention of SNR should be based on eliminating modifiable risk factors. We propose including screening for SNR symptoms in every ophthalmic examination, especially among patients with psychogenic or neural disorders, after brain trauma, or young adults spending much time in front of computer screens.

Visual Impairment from Uncorrected Refractive Error among Participants in a Novel Program to Improve Eye Care Access among Low-Income Adults in Michigan

PURPOSE

To assess the rate of visual impairment (VI) from uncorrected refractive error (URE) and associations with demographic and socioeconomic factors among low-income patients presenting to the Michigan Screening and Intervention for Glaucoma and Eye Health through Telemedicine (MI-SIGHT) program.

DESIGN

Cross-sectional study.

PARTICIPANTS

Adults ≥ 18 years without acute ocular symptoms.

METHODS

MI-SIGHT program participants received a telemedicine-based eye disease screening and ordered glasses through an online optical store. Participants were categorized based on refractive error (RE) status: VI from URE (presenting visual acuity [PVA], ≤ 20/50; best-corrected visual acuity [BCVA], ≥ 20/40), URE without VI (PVA, ≥ 20/40; ≥ 2-line improvement to BCVA), and no or adequately corrected RE (PVA, ≥ 20/40; < 2-line improvement to BCVA). Patient demographics, self-reported visual function, and satisfaction with glasses obtained through the program were compared among groups using analysis of variance, Kruskal-Wallis, chi-square, and Fisher exact testing.

MAIN OUTCOME MEASURES

PVA, BCVA, and presence of VI (defined as PVA ≤ 20/50).

RESULTS

Of 1171 participants enrolled in the MI-SIGHT program during the first year, average age was 55.1 years (SD = 14.5), 37.7% were male, 54.1% identified as Black, and 1166 (99.6%) had both PVA and BCVA measured. VI was observed in 120 participants (10.3%); 96 had VI from URE (8.2%), 168 participants (14.4%) had URE without VI, and 878 (75.3%) had no or adequately corrected RE. A smaller percentage of participants with VI resulting from URE reported having a college degree, and a larger percentage reported income < $10 000 compared with participants with no or adequately corrected RE (3.2% vs. 14.2% [P = 0.02]; 45.5% vs. 21.6% [P < 0.0001], respectively). Visual function was lowest among participants with VI from URE, followed by those with URE without VI, and then those with no or adequately corrected RE (9-item National Eye Institute Visual Function Questionnaire composite score, 67.3 ± 19.6 vs. 77.0 ± 14.4 vs. 82.2 ± 13.3, respectively; P < 0.0001). In total, 71.2% (n = 830) ordered glasses for an average cost of $36.80 ± $32.60; 97.7% were satisfied with their glasses.

CONCLUSIONS

URE was the main cause of VI at 2 clinics serving low-income communities and was associated with reduced vision-related quality of life. An online optical store with lower prices made eyeglasses accessible to low-income patients.

FINANCIAL DISCLOSURE(S)

Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.

Subjective versus objective refraction in healthy young adults

PURPOSE

To evaluate objective and subjective refraction differences in healthy young adults.

METHODS

Data concerning candidates for the Israeli Air Force Flight Academy, as well as active air force pilots in all stages of service who underwent a routine health checkup between the years 2018 and 2019 were retrospectively analyzed. Objective refraction measured using a single autorefractometer was compared with subjective refraction measured by an experienced military optometrist during the same visit. The results were converted to power vectors (spherical equivalent [SE], J0, and J45). To interpret astigmatism using power vector values, the cylinder power (Cp) was determined.

RESULTS

This study included 1,395 young adult participants. The average age was 22.17 years (range, 17-39, 84.8% males). The average SE was - 0.65 ± 1.19 diopter (D) compared with - 0.71 ± 0.91D in the auto- and subjective refraction, respectively (p = 0.001). Cp was 0.91 ± 0.52D and 0.67 ± 0.40D, respectively (p < 0.001). This difference was more common in older participants (p < 0.001). J0 and J45 value differences were not significant. The absolute SE value of subjective refraction was lower in the myopic (p < 0.001) and hyperopic (p < 0.001) patients.

CONCLUSIONS

Young hyperopic participants tended to prefer "less plus" in subjective refraction compared with autorefraction. Young myopic participants tended to prefer "less minus" in subjective refraction compared with autorefraction. All participants, but mainly older participants, preferred slightly "less Cp" than that measured using autorefraction; The astigmatic axis did not differ significantly between the methods.

Cutoff values of axial length/corneal radius ratio for determining myopia vary with age among 3-18 years old children and adolescents

PURPOSE

To investigate the effectiveness and cutoffs of axial length/corneal radius (AL/CR) ratio for myopia detection in children by age.

METHODS

Totally, 21 kindergartens and schools were enrolled. Non-cycloplegic autorefraction (NCAR), axial length (AL), horizontal and vertical meridian of corneal radius (CR1, CR2), and cycloplegic autorefraction were measured. Receiver operating characteristic (ROC) curve was used to obtain the effectiveness and cutoff for myopia detection.

RESULTS

Finally, 7803 participants aged 3-18 years with mean AL/CR ratio of 2.99 ± 0.16 were included. Area under the ROC curve (AUC) of AL/CR ratio for myopia detection (0.958 for AL/CR1, 0.956 for AL/CR2, 0.961 for AL/CR) was significantly larger than that of AL (0.919, all P < 0.001), while AUCs of the three were similar with different cutoffs (> 2.98, > 3.05, and > 3.02). When divided by age, the ROC curves of AL/CR ratio in 3- to 5-year-olds showed no significance or low accuracy (AUCs ≤ 0.823) in both genders. In ≥ 6-year-olds, the accuracies were promising (AUCs ≥ 0.883, all P < 0.001), the cutoffs basically increased with age (from > 2.93 in 6-year-olds to > 3.07 in 18-year-olds among girls, and from > 2.96 in 6-year-olds to > 3.07 in 18-year-olds among boys). In addition, boys presented slightly larger cutoffs than girls in all ages except for 16 and 18 years old. For children aged 3-5 years, AL/CR ratio or AL combined with NCAR increased AUC to > 0.900.

CONCLUSION

AL/CR ratio provided the best prediction of myopia with age-dependent cutoff values for all but preschool children, and the cutoffs of boys were slightly larger than those of girls. For preschool children, AL/CR ratio or AL combined with NCAR is recommended to achieve satisfactory accuracy. AL/CR ratio calculated by two meridians showed similar predictive power but with different cutoffs.

The impact of accommodation function on the difference between noncycloplegic and cycloplegic refraction in adult myopes

PURPOSE

To investigate the impact of accommodation function on the difference between cycloplegic and noncycloplegic subjective and automatic refraction in adult myopes.

METHODS

Myopic patients between 18 and 50 years old evaluated at Peking University Third Hospital who underwent cycloplegic and noncycloplegic automatic and subjective refraction were enrolled. Accommodation function, including negative and positive relative accommodation (PRA/NRA) and accommodation response (binocular cross cylinder, BCC) was examined.

RESULTS

Of the 3268 individuals enrolled, the mean age was 27.3 ± 6.9 years, and 34.8% of participants were male. The noncycloplegic spherical equivalent (SE) was 0.23 ± 0.29 D and 0.64 ± 0.61 D more myopic than cycloplegic subjective and automatic refraction. Adjusting for associated factors, participants with at least 0.50 D of more myopia SE refraction by noncycloplegic subjective refraction were more likely to be older (odds ratio [OR], 1.029; 95% confidence interval [CI], 1.013-1.045) and with insufficient (OR, 1.514; 95% CI, 1.093-2.096) and excessive (OR, 2.196; 95% CI, 1.538-3.137) NRA value. The automatic refraction SE difference of at least 1.00 D more myopia was more likely to be found in individuals with older age (OR, 1.036; 95% CI, 1.022-1.050) and accommodative lead (OR, 1.255; 95% CI, 1.004-1.568).

CONCLUSION

A quarter of adult myopes had at least 0.50 and 1.00 D of subjective and automatic SE difference with cycloplegia. The accommodation function significantly affects the difference between cycloplegic and noncycloplegic refraction. Investigating the differences in refraction measurement guarantees the proper use of cycloplegia in adults for myopia correction.

Tropicamide Versus Cyclopentolate for Cycloplegic Refraction in Pediatric Patients With Brown Irides: A Randomized Clinical Trial

PURPOSE

To compare the final cycloplegic refraction of tropicamide 1% and cyclopentolate 1% in children 3-16 years of age with brown irides.

DESIGN

Randomized, controlled, multicenter prospective clinical trial.

METHODS

Included patients were randomized to either cyclopentolate 1% or tropicamide 1% in the first visit with autorefraction measurements. Each subject underwent a second cycloplegic refraction using the other agent on a separate visit with a minimum of 1-week interval and a maximum of 12 weeks. We measured the change in SE (ΔSE) for each eye by deducting the SE before cycloplegia from the SE after cycloplegia.

RESULTS

A total of 185 eyes from 94 children aged 3-16 years (average= 8.79 ±3.11 years) were included. The average SE of both eyes before cycloplegia was -0.082 ± 4.8 diopters. The SE after instillation of cyclopentolate and tropicamide in both eyes was 1.07±5.2 and 0.96±5.1, respectively (P value < .001). The average ΔSE after cycloplegia was 1.15±1.2 for cyclopentolate and 1.04±1.2 for tropicamide (P value < .001). The difference between ΔSE of cyclopentolate and tropicamide was found statistically significant at 0.11±1.2 (P < .001), although clinically insignificant. The ΔSE between the 2 drops before and after cycloplegia in both eyes for all refractive error groups was clinically insignificant. The greatest effect of cyclopentolate and tropicamide was in hyperopic eyes with ΔSE of 1.54±1.4 and 1.39±1.4, respectively.

CONCLUSIONS

Tropicamide might be an effective and safe replacement for cyclopentolate in the refracting nonstrabismic pediatric population 3-16 years of age regardless of their refractive error status.

Axial length to corneal radius of curvature ratio and refractive error in Chinese preschoolers aged 4-6 years: a retrospective cross-sectional study

OBJECTIVE

This study aims to investigate the associations of axial length to corneal radius of curvature (AL/CRC) ratio with refractive error and to determine the effect of AL/CRC ratio on hyperopia reserve and myopia assessment among Chinese preschoolers.

METHODS

This was a retrospective cross-sectional study that evaluated subjects aged 4-6 years. AL and CRC were obtained using a non-contact ocular biometer. Correlation analysis was performed to explore the associations of AL/CRC ratio with spherical equivalent refractive error (SER). The accuracy of AL/CRC ratio for hyperopia reserve and myopia assessment was analysed using cycloplegic refraction by drawing receiver operating characteristic (ROC) curves.

RESULTS

The analysis included 1024 participants (537 boys, 52.4%). The mean AL/CRC ratios in hyperopes, emmetropes and myopes were 2.90±0.06, 2.95±0.05 and 3.08±0.07, respectively. The SER was found to be more strongly correlated with AL/CRC ratio (ρ=-0.66, p<0.001) than either AL or CRC alone (ρ=-0.52, p<0.001; ρ=-0.03, p=0.33, respectively). AL/CRC was correlated with SER in hyperopes (ρ=-0.54, p<0.001), emmetropes (ρ=-0.33, p<0.001) and myopes (r=-0.67, p<0.001). For low hyperopia reserve assessment, the area under the ROC curves of AL/CRC ratio was 0.861 (95% CI 0.829 to 0.892), the optimal cut-off value of the AL/CRC ratio was ≥2.955. For myopia assessment, the area under the ROC curves of AL/CRC ratio was 0.954 (95% CI 0.925 to 0.982), the optimal cut-off value of the AL/CRC ratio was ≥2.975.

CONCLUSIONS

The SER showed a better correlation with AL/CRC ratio than either AL or CRC alone, especially in myopes, among children aged 4-6 years. These findings indicate that when cycloplegic refraction is unavailable, AL/CRC ratio could be used as an alternative indicator for identifying low hyperopia reserve and myopia among preschoolers, helping clinicians and parents screen children with low hyperopia reserve before primary school in a timely manner.

Establishment of noncycloplegic methods for screening myopia and pre-myopia in preschool children

Purpose

Pre-myopia, a non-myopic refractive state, is a key concern for myopia prevention because of its association with a significantly higher risk of myopia in children under 3 years of age. Amid the myopia pandemic, its onset at younger ages is increasing, yet research on screening methods for myopia and pre-myopia in preschool children remains limited. This study aimed to establish effective noncycloplegic screening methods for myopia and pre-myopia in preschool children.

Methods

This cross-sectional study included 16 kindergartens in Shanghai, China. Uncorrected distance visual acuity (UDVA) was recorded using a logMAR visual acuity chart. Pre- and post-cycloplegic refractions were obtained using an auto-refractor (TopconKR-800). Noncycloplegic axial length (AL) and corneal curvature radius (CR) were measured using the IOL Master-700. Logistic regression models were developed to establish accurate noncycloplegic screening methods for myopia and pre-myopia.

Results

A total of 1,308 children with a mean age of 4.3 ± 0.9 years were included; among them 640 (48.9%) were girls. The myopia prevalence rate was 2.8% (n = 36), and the prevalence of pre-myopia was 21.9% (n = 286). Pre-myopia screening (cycloplegic spherical equivalent [SE] ≤ -0.5 < SE ≤0.75 diopters [D]) using UDVA exhibited an area under the receiver operating curve (AUC) of 0.52, noncycloplegic SE had an AUC of 0.70 and AL had an AUC of 0.63. The accuracy of combining the SE and AL/CR ratio was among the best with the least number of checks used, and the AUC was 0.74 for pre-myopia screening and 0.94 for myopia screening (cycloplegic SE ≤ -0.5 D). The addition of UDVA did not further improve the accuracy.

Conclusion

Using UDVA alone did not achieve good accuracy in pre-myopia or myopia screening of young children. Under non-cycloplegic conditions, the combination of AL/CR and SE demonstrated favorable results for pre-myopia and myopia screening of preschool children.

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

BACKGROUND

The 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.

METHODS

This 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.

RESULTS

All 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.

CONCLUSIONS

Myopia 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.

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

PURPOSE

By 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.

METHODS

Cross-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.

RESULTS

The 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.

CONCLUSION

This 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.

The Guiding Significance of Ocular Biometry in Evaluating the Refractive Status of Preschool Children

INTRODUCTIONS

This study aimed to analyze the correlation between refractive status and ocular biological parameters in preschool-age children (3-6 years old), establish a regression curve, guide the clinical judgment of children's refractive status, and improve the accuracy of refractive screening for this age group.

METHODS

A total of 508 children, aged 3-6 years, were admitted to the hospital, exhibiting symptoms of ametropia and a need for dilation optometry. Among these, 326 children were included in the statistics group, having been examined between August 2021 and October 2022, and 182 children were included in the validation group, having been examined between November 2022 and March 2023. Using IOL Master700, ocular biometry parameters were measured for all participants, including axial length (AL), keratometry readings (K1 and K2), anterior chamber depth (ACD), lens thickness (LT), and central corneal thickness (CCT). One percent atropine sulfate eye gel was administered, and then the spherical equivalent (SE) was calculated by Bennett's formula. The correlation between SE and other ocular biometrics was analyzed, followed by the establishment of an SE prediction equation. The SE prediction equation was used to calculate the spherical equivalent (SE#) using ocular biometry data from the validation group, and the consistency between SE and SE# was evaluated.

RESULTS

SE showed a negative correlation with AL/CR (r = -0.936), AL (r = -0.811), ACD (r = -0.500), age (r = -0.396), and Km (r = -0.213) (p < 0.001), and positive correlation with LT (r = 0.301), LP (r = 0.176) (p < 0.001). A multiple linear regression equation was established for SE using the stepwise selection method, SE = 49.232 - 23.583 × AL/CR + 1.703 × ACD + 0.589 × Km - 0.609 × LP + 1.103 × LT (R2 = 0.997). Based on the regression equation, the predicted SE# highly correlated with SE after cycloplegia in the validation group (r = 0.998, p < 0.001).

CONCLUSION

The main ocular biological factors of ocular diopter in children aged 3-6 years are AL/CR, ACD, Km, LP, and LT, which are jointly influenced by multiple factors. Ocular biometry is a reliable predictor of real refraction among children aged 3-6.

Accuracy and intrasession variability of noncycloplegic autorefraction of school-aged children and adolescents

The aims of the study were (1) to compare the accuracy and intrasession variability of noncycloplegic autorefraction (AR) obtained by a photorefractor and conventional and open-field autorefractors and (2) to evaluate the impact of accommodative and binocular vision anomalies on the accuracy of autorefraction. Twenty-nine children and adolescents aged 8-18 years were examined. All instruments gave more myopic results than subjective refraction (SR). Mean differences between the SR and the AR were +0.52/-0.25×96∘ for the photorefractor, +0.63/-0.31×93∘ for the conventional autorefractor, and +0.19/-0.26×94∘ for the open-field instrument. The photorefractor appeared to be the most repeatable. The impact of the examined vision anomalies on the accuracy of autorefraction was not statistically significant.

A large-scale analysis of refractive errors in students attending public primary schools in Mexico

A cross-sectional, retrospective study was conducted from September 2013 through July 2014 to determine the prevalence of refractive errors among students attending public primary schools in Mexico. Among 3,861,156 students at 14,566 public primary schools in all 32 states of Mexico, teachers identified reduced visual acuity in 1,253,589 (32.5%) using visual acuity measurement. Optometrists confirmed 391,498 [31.2%, mean (SD) age: 8.8 (1.9) years; 204,110 girls (52.9%)] had refractive errors using visual acuity measurement and noncycloplegic static retinoscopy. Among 288,537 (72.4%) of children with previous eyeglasses usage data reported, 241,505 (83.7%) had uncorrected refractive errors. Before prescription eyeglasses were provided, 281,891 students (72%) had logMAR visual acuity ≤ 0.2; eyeglasses corrected vision loss in 85.6% (n = 241,352) of them. Simple myopic astigmatism was the most frequent refractive error (25.7%, n = 100,545). Astigmatism > - 1.00 diopters was present in 54.6% of all students with ametropia. The anisometropia rate based on spherical equivalent difference between right and left eye ≥ 1.50 diopters was 3.9% (n = 15,402). Uncorrected refractive errors are an important issue in primary school students in Mexico. An updated study is needed to analyze the evolving trends over the past decade.

The Influence of Accommodation on Retinal Peripheral Refraction Changes in Different Measurement Areas

Background

The change in refraction caused by accommodation inevitably affects the peripheral defocus state and thus may influence the effect of retinal peripheral myopic defocus measures in myopia control. This study investigated accommodation changes in different peripheral retinas under cycloplegia to help improve myopia control.

Methods

Fifty-six eyes of fifty-six myopic subjects were recruited for this prospective study. The center and peripheral retina refractions were measured using multispectral refractive topography. The subjects were divided into low-to-moderate myopia group (range: -1.25 D to -6.00 D) and high myopia group (range: -6.25 D to -9.75 D) according to spherical equivalent (SE). The compound tropicamide (0.5% tropicamide and 0.5% phenylephrine) was used to relax the accommodation. The difference between cycloplegia and non-cycloplegia peripheral retinal refraction was analyzed using the t-test. The correlation between eccentricity and changes in peripheral refraction was analyzed using Pearson's correlation analysis.

Results

The manifest refraction of the retina significantly decreased with an increase in eccentricity after cycloplegia. The annular refraction difference value at 50°-53° (ARDV 50-53) showed the largest refraction decrease of 1.31 D compared with the central retinal refraction decrease of 0.84 D. The inferior quadrantal refraction difference value had the least change compared to the other quadrants. The relative peripheral refraction (RPR) changes in refraction difference value (RDV) at 15° (RDV-15), RDV-30, and RDV-45 were less than 0.15 D. When the range of annulus narrowed to 5°, the narrower annulus showed faster change with eccentricity increase in ARDV 30-35, ARDV 35-40, ARDV 40-45, ARDV 45-50, and ARDV 50-53. The RPR was highly correlated with eccentricity (R = 0.938 and P < 0.001). The high myopia group had a greater hyperopic shift in the periphery than the low-to-moderate group after cycloplegia.

Conclusions

Peripheral refraction showed a significant hyperopic shift after cycloplegia with an increase in eccentricity. The RPR became more hyperopic than the central refraction. The high myopia group showed more hyperopic shifts in the peripheral region. Accommodation should be taken into consideration in peripheral defocus treatment.

Evaluation of a Pilot Protocol for Detecting Infant Hyperopia

SIGNIFICANCE

Highly hyperopic children are at greater risk for developing conditions such as strabismus, amblyopia, and early literacy and reading problems. High hyperopia is a common finding in infants in a pediatric medical practice, and early detection can be done effectively in that setting with tropicamide autorefraction.

PURPOSE

This study aimed to evaluate the effectiveness of a pilot screening program to detect high hyperopia in 2-month-old infants in a pediatric medical practice in Columbus, Ohio.

METHODS

Cycloplegic refractive error (1% tropicamide) was measured by retinoscopy and autorefraction with the Welch Allyn SureSight (Welch Allyn/Hillrom, Skaneateles Falls, NY) in 473 infants (55.4% female) who were undergoing their 2-month well-baby visit at their pediatrician's medical practice. Cycloplegic retinoscopy (1% cyclopentolate) was repeated at a subsequent visit in 35 infants with ≥+5.00 D hyperopia in the most hyperopic meridian during the screening.

RESULTS

Twenty-eight infants (5.9%) had high hyperopia (spherical equivalent, ≥+5.00 D), and 61 (12.9%) had high hyperopia (≥+5.00 D in at least one meridian of at least one eye) by retinoscopy with 1% tropicamide. The mean ± standard deviation spherical equivalent tropicamide cycloplegic refractive error measured with retinoscopy was +2.54 ± 1.54 D (range, -3.25 to +7.00 D) and with SureSight was +2.29 ± 1.64 D (range, -2.90 to +7.53 D). Retinoscopy done using 1% cyclopentolate was 0.44 ± 0.54 D more hyperopic in spherical equivalent than with 1% tropicamide ( P < .001).

CONCLUSIONS

High hyperopia was a common finding in 2-month-old infants in a pediatric medical setting that could be detected effectively by cycloplegic autorefraction using tropicamide. Greater cooperation between pediatric primary vision and medical care could lead to effective vision screenings designed to detect high hyperopia in infants.

Evaluation of the Prevalence of Refractive Defects and Ocular Function in a Group of 1518 Children Aged 8 Years in Northwestern Poland-A Retrospective Study

PURPOSE

To determine the prevalence of refractive errors in a group of 8-year-old school children in northwestern Poland.

MATERIAL AND METHODS

In 2017-2019, refractive errors were examined in a group of 1518 Caucasian children aged 8 years old with cycloplegia. Refraction was obtained with a hand-held autorefractor (Retinomax 3). The refractive error reading was expressed as the spherical equivalent (SE) as myopia (≤-0.5 D), emmetropia (>-0.5 D to ≤+0.5 D), mild hyperopia (>+0.5 D to ≤+2.0 D) and hyperopia (>+2.0 D), and astigmatism (≤-0.75 DC) and anisometropia (≥1.00 D). Data analysis was performed using Statistica 13.5 software and included Pearson's chi-squared and Mann-Whitney U tests. p-values of <0.05 were considered statistically significant.

RESULTS

Mild hyperopia was most common (37.6%), myopia was observed in 16.8% and astigmatism in 10.6% of participants. Pseudomyopia concerned up to 51.91% children. Girls were significantly more likely to have mild hyperopia (p = 0.0144) and were significantly more likely to wear glasses (p = 0.00093).

CONCLUSIONS

Screening children for refractive errors after cycloplegia is key for detecting accommodative spasm and refractive errors. The largest group of children presented with mild hyperopia, which is a physiological feature of refraction in 8-year-old children, but myopia and astigmatism were the most common refractive errors.

Analysis of 2-year spherical equivalent progression in emmetropic children with non-cycloplegic refraction: a retrospective chart review

BACKGROUND

We aimed to investigate children with an emmetropic non-cycloplegic refraction (NCR) to compare the difference in progression of NC spherical equivalent (SE) over 2 years between the children with emmetropic and hyperopic cycloplegic refraction (CR) values.

METHODS

Through a retrospective medical record review, 59 children aged under 10 years were evaluated. Refractive error was calculated as the average of the SE values of both eyes. According to the CR results, children with emmetropia (-0.50 to 1.00 diopter [D]) were assigned to group 1 (n = 29), and those with hyperopia (≥ 1.00 D) were assigned to group 2 (n = 30). The prevalence of myopia and SE progression were compared over 2 years. Correlations between final SE progression and baseline age and refractive error were analyzed and multiple regression analysis was conducted. Receiver operating characteristic curves that achieved the best cutoff points to distinguish between the groups were calculated.

RESULTS

Group 1 showed significantly myopic SE changes compared to baseline at the 1-year follow-up, and group 1 was significantly myopic compared with group 2 at the 2-year follow-up. Myopia prevalence was 51.7% in group 1 and 6.7% in group 2 after 1 year, and 61.1% and 16.7% after 2 years, respectively. In the correlation analysis, baseline age, baseline CR, and difference between CR and NCR showed significant correlations with the 2-year SE progression (r = -0.359, p = 0.005; r = 0.450, p < 0.001; r = -0.562, p < 0.001, respectively). However, NCR refractive error showed no significant correlation (r = -0.097, p = 0.468). In multiple regression analysis, baseline age (β= -0.082), and CR-NCR difference (β= -0.214) showed a significant effect on SE progression for 2 years. When an NCR value of 0.20 D was set as the cut-off value to distinguish between the groups, a sensitivity of 70% and specificity of 92% were obtained.

CONCLUSION

Even if NCR showed emmetropia, children with baseline CR values of emmetropia showed greater SE progression compared with those with hyperopia. Cycloplegia is essential to confirm the correct refractive status in children. It may be useful for predicting prognosis of SE progression.

Emmetropization and nonmyopic eye growth

Most eyes start with a hypermetropic refractive error at birth, but the growth rates of the ocular components, guided by visual cues, will slow in such a way that this refractive error decreases during the first 2 years of life. Once reaching its target, the eye enters a period of stable refractive error as it continues to grow by balancing the loss in corneal and lens power with the axial elongation. Although these basic ideas were first proposed over a century ago by Straub, the exact details on the controlling mechanism and the growth process remained elusive. Thanks to the observations collected in the last 40 years in both animals and humans, we are now beginning to get an understanding how environmental and behavioral factors stabilize or disrupt ocular growth. We survey these efforts to present what is currently known regarding the regulation of ocular growth rates.

Association between sleep duration and myopia among Chinese children during the COVID-19 pandemic: A cross-sectional study

Background

The studies on the association between sleep duration and myopia are limited, and the evidence is inconsistent. This study aimed to evaluate the association between sleep duration and myopia, cycloplegic spherical equivalent (SE) and axial length (AL) among Chinese children during the Corona Virus Disease 2019 (COVID-19) pandemic.

Methods

The study was a cross-sectional study on Chinese children aged 6-18 years. The comprehensive ophthalmic examinations for children included cycloplegic SE, AL, and standardized questionnaires. The questionnaire included sleep duration, parental myopia, outdoor time, and continuous near work duration without breaks. Myopia was defined as SE ≤-0.50 diopters (D).

Results

A total of 1,140 children were included in the analyses, with 84.7% of myopic children and 74.4% of children's daily sleep duration being more than 8 h/d. In univariate regression analysis, compared with sleep duration < 8 h/d, children with sleep duration of 8-9 and >9 h/d were less myopia (p < 0.01 for all), and had less myopic SE (p < 0.01 for all), and shorter AL (p < 0.01 for all). After adjusting for age, gender, parental myopia, outdoor time, and continuous near work duration without breaks, sleep duration was not associated with myopia, cycloplegic SE, and AL (p > 0.05 for all).

Conclusions

This study showed sleep duration was related to myopia, cycloplegic SE, and AL among Chinese children during the COVID-19 pandemic-related lifestyles, but no independent association.

Comparison of an open view autorefractor with an open view aberrometer in determining peripheral refraction in children

PURPOSE

The aim of this study was to compare central and peripheral refraction using an open view Shin-Nippon NVision-K 5001 autorefractor and an open view COAS-HD VR aberrometer in young children.

METHODS

Cycloplegic central and peripheral autorefraction was measured in the right eye of 123 children aged 8 to 16 years. Three measurements each were obtained with both Shin-Nippon NVision-K 5001 autorefractor and COAS-HD VR aberrometer along the horizontal visual field up to 30° (nasal and temporal) in 10° steps. The refraction from the autorefractor was compared with aberrometer refraction for pupil analysis diameters of 2.5-mm and 5.0-mm.

RESULTS

The Shin-Nippon was 0.30 D more hyperopic than COAS-HD VR at 2.5-mm pupil and 0.50 D more hyperopic than COAS-HD VR at 5-mm pupil for central refraction. For both pupil sizes, the 95% limits of agreement were approximately 0.50 D for central refraction, and limits were wider in the nasal visual field compared to the temporal visual field. The mean difference for both J₀ and J₄₅ were within 0.15 D and the 95% limits of agreement within 0.90 D across the horizontal visual field.

CONCLUSION

Defocus components were similar between the Shin-Nippon autorefractor and the COAS-HD VR aberrometer with a 2.5-mm pupil for most visual field angles. However, there was a significant difference in defocus component between the Shin-Nippon autorefractor and the COAS-HD VR aberrometer with a 5.0-mm pupil, wherein the autorefractor measured more hyperopia. The astigmatic components J₀ and J₄₅ were similar between instruments for both central and peripheral refraction.

Prediction of spherical equivalent difference before and after cycloplegia in school-age children with machine learning algorithms

Purpose

To predict the need for cycloplegic assessment, as well as refractive state under cycloplegia, based on non-cycloplegic ocular parameters in school-age children.

Design

Random cluster sampling.

Methods

The cross-sectional study was conducted from December 2018 to January 2019. Random cluster sampling was used to select 2,467 students aged 6-18 years. All participants were from primary school, middle school and high school. Visual acuity, optical biometry, intraocular pressure, accommodation lag, gaze deviation in primary position, non-cycloplegic and cycloplegic autorefraction were conducted. A binary classification model and a three-way classification model were established to predict the necessity of cycloplegia and the refractive status, respectively. A regression model was also developed to predict the refractive error using machine learning algorithms.

Results

The accuracy of the model recognizing requirement of cycloplegia was 68.5-77.0% and the AUC was 0.762-0.833. The model for prediction of SE had performances of R^2 0.889-0.927, MSE 0.250-0.380, MAE 0.372-0.436 and r 0.943-0.963. As the prediction of refractive error status, the accuracy and F1 score was 80.3-81.7% and 0.757-0.775, respectively. There was no statistical difference between the distribution of refractive status predicted by the machine learning models and the one obtained under cycloplegic conditions in school-age students.

Conclusion

Based on big data acquisition and machine learning techniques, the difference before and after cycloplegia can be effectively predicted in school-age children. This study provides a theoretical basis and supporting evidence for the epidemiological study of myopia and the accurate analysis of vision screening data and optometry services.

Comparisons of objective and subjective refraction with and without cycloplegia using binocular wavefront optometer with autorefraction and retinoscopy in school-age children

Purpose

To compare school-age children’s objective and subjective refraction using a binocular wavefront optometer (BWFOM) with autorefraction and retinoscopy before and after cycloplegia.

Methods

Eighty-six eyes from 86 children (6–15 years old) were enrolled in this cross-sectional study. BWFOM objective and subjective refractions were compared with autorefraction and retinoscopy under cycloplegia. BWFOM refraction was evaluated before and after cycloplegia. Measurements were compared using a paired t-test; agreement was assessed using Bland–Altman plots.

Results

Under cycloplegia, the sphere, spherical equivalence, and J45 were significantly more negative on BWFOM objective refraction than autorefraction (− 1.39 ± 2.20 D vs. − 1.28 ± 2.23 D, P = 0.003; − 1.84 ± 2.38 D vs. − 1.72 ± 2.43 D, P = 0.001; − 0.02 ± 0.17 D vs. 0.03 ± 0.21 D, P = 0.004). The subjective sphere of BWFOM was less myopic, and the cylinder and the J45 were more negative than those with retinoscopy (− 1.17 ± 2.09 D vs. − 1.25 ± 2.20 D, P = 0.02; − 0.91 ± 0.92 D vs. − 0.76 ± 0.92 D, P < 0.001; − 0.01 ± 0.15 D vs. 0.03 ± 0.21 D, P = 0.028). For both BWFOM objective and subjective refraction, sphere and spherical equivalence with noncycloplegia were more myopic than those with cycloplegia (objective: − 1.76 ± 2.10 D vs. − 1.39 ± 2.20 D, − 2.21 ± 2.30 D vs. − 1.84 ± 2.38 D, P < 0.001; subjective: − 1.57 ± 1.92 D vs. − 1.17 ± 2.09 D, − 2.01 ± 2.13 D vs. − 1.62 ± 2.27 D, P < 0.001). Bland–Altman plots showed good agreement in spherical equivalence between BWFOM objective refraction and autorefraction (mean difference = 0.12 D, 95% confidence interval [CI] − 0.52 to 0.76), subjective refraction with retinoscopy (mean difference =  − 0.01 D, 95% CI − 0.65 to 0.64), and BWFOM refractions with or without cycloplegia (objective: mean difference =  − 0.37 D, 95% CI − 1.31 to 0.57; subjective: mean difference =  − 0.39 D, 95% CI − 1.30 to 0.51). The time cost by BWFOM was significantly less than the total time of autorefraction and retinoscopy (264.88 ± 90.67 s vs. 315.89 ± 95.31 s, P < 0.001).

Conclusion

BWFOM is a new device that realizes both objective and subjective refraction. For children’s refractive errors, it is more convenient and quicker to obtain the proper prescription at a 0.05-D interval, and it is more accurate than autorefraction and retinoscopy under cycloplegia.

Identification of ocular refraction based on deep learning algorithm as a novel retinoscopy method

BACKGROUND

The evaluation of refraction is indispensable in ophthalmic clinics, generally requiring a refractor or retinoscopy under cycloplegia. Retinal fundus photographs (RFPs) supply a wealth of information related to the human eye and might provide a promising approach that is more convenient and objective. Here, we aimed to develop and validate a fusion model-based deep learning system (FMDLS) to identify ocular refraction via RFPs and compare with the cycloplegic refraction. In this population-based comparative study, we retrospectively collected 11,973 RFPs from May 1, 2020 to November 20, 2021. The performance of the regression models for sphere and cylinder was evaluated using mean absolute error (MAE). The accuracy, sensitivity, specificity, area under the receiver operating characteristic curve, and F1-score were used to evaluate the classification model of the cylinder axis.

RESULTS

Overall, 7873 RFPs were retained for analysis. For sphere and cylinder, the MAE values between the FMDLS and cycloplegic refraction were 0.50 D and 0.31 D, representing an increase of 29.41% and 26.67%, respectively, when compared with the single models. The correlation coefficients (r) were 0.949 and 0.807, respectively. For axis analysis, the accuracy, specificity, sensitivity, and area under the curve value of the classification model were 0.89, 0.941, 0.882, and 0.814, respectively, and the F1-score was 0.88.

CONCLUSIONS

The FMDLS successfully identified the ocular refraction in sphere, cylinder, and axis, and showed good agreement with the cycloplegic refraction. The RFPs can provide not only comprehensive fundus information but also the refractive state of the eye, highlighting their potential clinical value.

Comparison of lens refractive parameters in myopic and hyperopic eyes of 6-12-year-old children

Background/aims

To evaluate the influence of cycloplegia on lens refractive parameters in 6-12-year-old children with myopia and hyperopia for exploring the pathogenesis of myopia.

Methods

One hundred eyes of 100 patients (50 boys) were included. In the myopic group, 50 subjects (25 boys and 25 right eyes) were enrolled with a mean age of 9.20 ± 1.69 years. IOLMaster 700 measurements were performed pre- and post-cycloplegia. The pictures were marked using semi-automatic software. The lens curvature and power were obtained using MATLAB image processing software. Paired and independent sample t-tests were used for data analysis. Statistical significance was set at P < 0.05.

Results

Anterior and posterior lens curvature radius in myopic eyes were larger than those in hyperopic eyes, both pre- and post-cycloplegia (both P < 0.001). The refractive power in myopic eyes was lower than that in hyperopic eyes without cycloplegia, both pre- and post-cycloplegia (both P < 0.001). The changes in anterior lens curvature and refractive power between pre- and post-cycloplegia in hyperopic eyes were larger than those in myopic eyes (both P < 0.05). No significant difference was found in the change in posterior lens curvature and refractive power after cycloplegia in hyperopic and myopic eyes (P > 0.05).

Conclusion

Anterior and posterior surfaces of the lens were flatter, and the refractive power was lower in the myopia group than in the hyperopia group. Myopic and hyperopic patients showed a tendency for lens flattening and refractive power decrease after cycloplegia. Hyperopic patients had more changes in anterior lens curvature and refractive power after cycloplegia.

Effect of six different autorefractor designs on the precision and accuracy of refractive error measurement

PURPOSE

To evaluate the precision of objective refraction measurements with six different autorefractors that have different designs and measurement principles and to compare the objective refraction values with the subjective refraction.

METHOD

Objective refraction of 55 participants was measured using six autorefractors with different designs. The instrument features mainly varied in terms of measurement principles, inbuilt fogging, open or closed view, and handheld or stationary designs. Two repeated measurements of objective refraction were performed with each autorefractor. The objective refractions from the six autorefractors were compared with the standard subjective refraction. The repeatability limit and Bland-Altman were used to describe the precision and accuracy of each autorefractor, respectively. The analysis was done using the spherical component of the refraction and the power-vector components, spherical equivalent (M), and cylindrical vectors.

RESULTS

The repeatability of all autorefractors was within 1.00 and 0.35D for measuring the M and both cylindrical components, respectively. Inbuilt fogging was the common feature of the instruments that showed better repeatability. Compared to subjective refraction, the mean difference for sphere and M was below +0.50D, and it was close to zero for the cylindrical components. The instruments that had inbuilt fogging showed narrower limit of agreement. When combined with fogging, the open field refractors showed better precision and accuracy.

CONCLUSIONS

The inbuilt fogging is the most important feature followed by the open view in determining the precision and accuracy of the autorefractor values.

Ocular Cyclopentolate: A Mini Review Concerning Its Benefits and Risks

Cycloplegic and mydriatic agents are essential in ophthalmological clinical practice since they provide the means for diagnosing and treating certain eye conditions. In addition, cyclopentolate has proven to possess certain benefits compared to other available cycloplegics and mydriatics. Still, the incidence of some adverse drug reactions related to this drug, especially in susceptible patients, has created interest in reviewing the literature about the benefits and risks of using cyclopentolate. A literature search was conducted in Medline/PubMed and Google Scholar, focusing on identifying cyclopentolate's benefits and risks; the most important benefit was its usefulness for evaluating refractive errors, especially for hyperopic children, pseudomyopia, anterior uveitis, treatment of childhood myopia, idiopathic vision loss, and during examinations before refractive surgery, with particular advantages compared to other cycloplegics. While the risks were divided into local adverse drug reactions such as burning sensation, photophobia, hyperemia, punctate keratitis, synechiae, and blurred vision, which are relatively frequent but mild and temporary; and systemic adverse drug reactions such as language problems, visual or tactile hallucinations and ataxia, but unlike ocular, systemic adverse drug reactions are rare and occur mainly in patients with risk factors. In addition, six cases of abuse were found. The treatment with cyclopentolate is effective and safe in most cases; nevertheless, special care must be taken due to the potential severe ADRs that may occur, especially in susceptible patients like children, geriatrics, patients with neurological disorders or Down's syndrome, patients with a low blood level of pseudocholinesterase, users of substances with CNS effects, and patients with a history of drug addiction. The recommendations are avoiding the use of 2% cyclopentolate and instead employing solutions with lower concentrations, preferably with another mydriatic such as phenylephrine. Likewise, the occlusion of the nasolacrimal duct after instillation limits the drug's absorption, reducing the risk of systemic adverse events.

Normal range of ocular biometry in healthy children: A systemic review and meta-analysis of 33,559 individuals under seven years of age

PURPOSE

To conduct a systemic review and meta-analysis on the normative range of ocular biometry in healthy children under seven years of age.

METHODS

A literature search was performed using the PubMed (MEDLINE) database. The main outcomes were normative values of axial length (AL), central corneal thickness (CCT), cornea curvature (CC), anterior chamber depth (ACD), lens thickness (LT) and vitreous chamber depth (VCD). Pooled estimates were obtained with a random-effects meta-analysis. Multivariate meta-regressions ascertained the moderator-related trends.

RESULTS

We included 47 studies for a total of 33,559 subjects. The pooled ALs for 0.0-1.9 years, 2.0-3.9 years and 4.0-6.9 years were 18.33 mm (95% confidence interval [CI] 17.57-19.09), 21.71 mm (21.49-21.93) and 22.37 mm (22.29-22.45), respectively. Children aged 0.0-1.9 years had a greater CCT (576.70 μm, 567.20-586.21), steeper cornea (7.41 mm, 7.16-7.65) and shallower ACD (2.46 mm, 2.23-2.69). LT ranged from 3.65 to 3.74 mm for 0-6 years, and VCD increased from 11.94 mm at birth to 15.36 mm at 4.0-6.9 years. Differences in AL between East Asian and non-East Asian children were found below two years of age (17.30 mm vs. 18.40 mm, p = 0.008) and for CC at 4.0-6.9 years of age (7.82 mm vs. 7.79 mm, p = 0.004). In a multivariate meta-regression, AL, CC, ACD and VCD increased with age (p < 0.05 for all), while CCT decreased with age (p = 0.0007).

CONCLUSIONS

This study reports normative data for ocular biometry in children. Few differences were found with ethnicity in the ocular biometry of infants and pre-schoolers.

Systematic review and meta-analysis on the agreement of non-cycloplegic and cycloplegic refraction in children

OBJECTIVE

To determine the diagnostic agreement of non-cycloplegic and cycloplegic refraction in children.

METHOD

The study methodology followed Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Electronic databases were searched for comparative studies exploring refraction performed on children under non-cycloplegic and cycloplegic conditions. There was no restriction on the year of publication; however, only publications in the English language were eligible. Inclusion criteria consisted of children aged ≤12 years, any degree or type of refractive error, either sex and no ocular or binocular co-morbidities. The QUADAS-2 tool was used to evaluate the risk of bias. Meta-analysis was conducted to synthesise data from all included studies. Subgroup and sensitivity analyses were undertaken for those studies with a risk of bias.

RESULTS

Ten studies consisting of 2724 participants were eligible and included in the meta-analysis. The test for overall effect was not significant when comparing non-cycloplegic Plusoptix and cycloplegic autorefractors (Z = 0.34, p = 0.74). The pooled mean difference (MD) was -0.08 D (95% CI -0.54 D, +0.38 D) with a prediction interval of -1.72 D to +1.56 D. At less than 0.25 D, this indicates marginal overestimation of myopia and underestimation of hyperopia under non-cycloplegic conditions. When comparing non-cycloplegic autorefraction with a Retinomax and Canon autorefractor to cycloplegic refraction, a significant difference was found (Z = 9.79, p < 0.001) and (Z = 4.61, p < 0.001), respectively.

DISCUSSION

Non-cycloplegic Plusoptix is the most useful autorefractor for estimating refractive error in young children with low to moderate levels of hyperopia. Results also suggest that cycloplegic refraction must remain the test of choice when measuring refractive error ≤12 years of age. There were insufficient data to explore possible reasons for heterogeneity. Further research is needed to investigate the agreement between non-cycloplegic and cycloplegic refraction in relation to the type and level of refractive error at different ages.

Regional variations and temporal trends of childhood myopia prevalence in Africa: A systematic review and meta-analysis

PURPOSE

To provide contemporary and future estimates of childhood myopia prevalence in Africa.

METHODS

A systematic online literature search was conducted for articles on childhood (≤18 years) myopia (spherical equivalent [SE] ≤ -0.50D; high myopia: SE ≤ -6.00D) in Africa. Population- or school-based cross-sectional studies published from 1 Jan 2000 to 30 May 2021 were included. Meta-analysis using Freeman-Tukey double arcsine transformation was performed to estimate the prevalence of childhood myopia and high myopia. Myopia prevalence from subgroup analyses for age groups and settings were used as baseline for generating a prediction model using linear regression.

RESULTS

Forty-two studies from 19 (of 54) African countries were included in the meta-analysis (N = 737,859). Overall prevalence of childhood myopia and high myopia were 4.7% (95% CI: 3.3%-6.5%) and 0.6% (95% CI: 0.2%-1.1%), respectively. Estimated prevalence across the African regions was highest in the North (6.8% [95% CI: 4.0%-10.2%]), followed by Southern (6.3% [95% CI: 3.9%-9.1%]), East (4.7% [95% CI: 3.1%-6.7%]) and West (3.5% [95% CI: 1.9%-6.3%]) Africa. Prevalence from 2011 to 2021 was approximately double that from 2000 to 2010 for all studies combined, and between 1.5 and 2.5 times higher for ages 5-11 and 12-18 years, for boys and girls and for urban and rural settings, separately. Childhood myopia prevalence is projected to increase in urban settings and older children to 11.1% and 10.8% by 2030, 14.4% and 14.1% by 2040 and 17.7% and 17.4% by 2050, respectively; marginally higher than projected in the overall population (16.4% by 2050).

CONCLUSIONS

Childhood myopia prevalence has approximately doubled since 2010, with a further threefold increase predicted by 2050. Given this trajectory and the specific public health challenges in Africa, it is imperative to implement basic myopia prevention programmes, enhance spectacle coverage and ophthalmic services and generate more data to understand the changing myopia epidemiology to mitigate the expanding risk of the African population.

Using electronic medical record data to establish and monitor the distribution of refractive errors. JOURNAL OF OPTOMETRY 2022;15 Suppl 1:S32-S42. [PMID: 36220741 PMCID: PMC9732486 DOI: 10.1016/j.optom.2022.09.001]

OBJECTIVE

To establish the baseline distribution of refractive errors and associated factors amongst a population that attended primary care optometry clinics.

DESIGN

Retrospective cross sectional cohort study of electronic medical records (EMR).

METHODS

Electronic medical record data was extracted from forty optometry clinics, representing a mix of urban and rural areas in Ireland. The analysis was confined to demographic and clinical data gathered over a sixty-month period between 2015 and 2019. Distribution rates were calculated using the absolute and relative frequencies of refractive error in the dataset, stratified for age and gender using the following definitions: high myopia ≤ -6.00 D, myopia ≤ -0.50 D, hyperopia ≥ +0.50 D, astigmatism ≤ -0.75 DC and anisometropia ≥ 1.00 D. Visual acuity data was used to explore vision impairment rates in the population. Further analysis was carried out on a gender and age-adjusted subset of the EMR data, to match the proportion of patients in each age grouping to the population distribution in the most recent (2016) Irish census.

RESULTS

153,598 clinic records were eligible for analysis. Refractive errors ranged from -26.00 to +18.50 D. Myopia was present in 32.7%, of which high myopia represented 2.4%, hyperopia in 40.1%, astigmatism in 38.3% and anisometropia in 13.4% of participants. The clinic distribution of hyperopia, astigmatism and anisometropia peaked in older age groups, whilst the myopia burden was highest amongst people in their twenties. A higher proportion of females were myopic, whilst a higher proportion of males were hyperopic and astigmatic. Vision impairment (LogMAR > 0.3) was present in 2.4% of participants. In the gender and age- adjusted distribution model, myopia was the most common refractive state, affecting 38.8% of patients.

CONCLUSION

Although EMR data is not representative of the population as a whole, it is likely to provide a reasonable representation of the distribution of clinically significant (symptomatic) refractive errors. In the absence of any ongoing traditional epidemiological studies of refractive error in Ireland, this study establishes, for the first time, the distribution of refractive errors observed in clinical practice settings. This will serve as a baseline for future temporal trend analysis of the changing pattern of the distribution of refractive error in EMR data. This methodology could be deployed as a useful epidemiological resource in similar settings where primary eyecare coverage for the management of refractive error is well established.

Systematic Review and Meta-Analysis on the Impact of COVID-19 Pandemic-Related Lifestyle on Myopia

PURPOSE

To conduct a systematic review and meta-analysis to assess the effects of coronavirus disease 2019 (COVID-19) pandemic-related lifestyle on myopia outcomes in children to young adults.

METHODS

A systematic search was conducted on PubMed, Embase, and the Cochrane Central Register of Controlled Trials databases (with manual searching of reference lists of reviews). Studies included assessed changes in myopia-related outcomes (cycloplegic refraction) during COVID and pre-COVID. Of 367 articles identified, 7 (6 prospective cohorts; 1 repeated cross-sectional study) comprising 6327 participants aged 6 to 17 were included. Quality appraisals were performed with Joanna Briggs Institute Critical Appraisal Checklists. Pooled differences in annualized myopic shifts or mean spherical equivalent (SE) during COVID and pre-COVID were obtained from random-effects models.

RESULTS

In all 7 studies, SE moved toward a myopic direction during COVID (vs pre-COVID), where 5 reported significantly faster myopic shifts [difference in means of changes: -1.20 to -0.35 diopters per year, [D/y]; pooled estimate: -0.73 D/y; 95% confidence interval (CI): -0.96, -0.50; P<0.001], and 2 reported significantly more myopic SE (difference in means: -0.72 to -0.44 D/y; pooled estimate: -0.54 D/y; 95% CI: -0.80, -0.28; P<0.001). Three studies reported higher myopia (SE ≤-0.50 D) incidence (2.0- to 2.6-fold increase) during COVID versus pre-COVID. Of studies assessing lifestyle changes, all 4 reported lower time outdoors (pre-COVID vs during COVID: 1.1-1.8 vs 0.4-1.0 hours per day, [h/d]), and 3 reported higher screen time (pre-COVID vs during COVID: 0.7-2.8 vs 2.4-6.9 h/d).

CONCLUSIONS

This review suggests more myopic SE shifts during COVID (vs pre-COVID) in participants aged 6 to 17. COVID-19 restrictions may have worsened SE shifts, and lifting of restrictions may lessen this effect. Evaluations of the long-term effects of the pandemic lifestyle on myopia onset and progression in large studies are warranted to confirm these findings.

Accommodation lags are higher in myopia than in emmetropia: Measurement methods and metrics matter

Purpose

To determine whether accommodative errors in emmetropes and myopes are systematically different, and the effect of using different instruments and metrics.

Methods

Seventy‐six adults aged 18–27 years comprising 24 emmetropes (spherical equivalent refraction of the dominant eye +0.04 ± 0.03 D) and 52 myopes (−2.73 ± 0.22 D) were included. Accommodation responses were measured with a Grand Seiko WAM‐5500 and a Hartmann–Shack Complete Ophthalmic Analysis System aberrometer, using pupil plane (Zernike and Seidel refraction) and retinal image plane (neural sharpness—NS; and visual Strehl ratio for modulation transfer function—VSMTF) metrics at 40, 33 and 25 cm. Accommodation stimuli were presented to the corrected dominant eye, and responses, referenced to the corneal plane, were determined in the fellow eye. Linear mixed‐effects models were used to determine influence of the refractive group, the measurement method, accommodation stimulus, age, race, parental myopia, gender and binocular measures of heterophoria, accommodative convergence/accommodation and convergence accommodation/convergence ratios.

Results

Lags of accommodation were affected significantly by the measurement method (p < 0.001), the refractive group (p = 0.003), near heterophoria (p = 0.002) and accommodative stimulus (p < 0.05), with significant interactions between some of these variables. Overall, emmetropes had smaller lags of accommodation than myopes with respective means ± standard errors of 0.31 ± 0.08 D and 0.61 ± 0.06 D (p = 0.003). Lags were largest for the Grand Seiko and Zernike defocus, intermediate for NS and VSMTF, and least for Seidel defocus.

Conclusions

The mean lag of accommodation in emmetropes is approximately equal to the previously reported depth of focus. Myopes had larger (double) lags than emmetropes. Differences between methods and instruments could be as great as 0.50 D, and this must be considered when comparing studies and outcomes. Accommodative lag increased with the accommodation stimulus, but only for methods using a fixed small pupil diameter.

Noncycloplegic Compared with Cycloplegic Refraction in a Chicago School-Aged Population

PURPOSE

To evaluate differences between autorefraction measurements with and without cycloplegia among school-aged individuals and to explore factors associated with significant differences.

DESIGN

Cross-sectional, retrospective study.

PARTICIPANTS

Individuals between 3 and 22 years of age evaluated at the Illinois College of Optometry from September 2016 through June 2019 who underwent same-day noncycloplegic and cycloplegic autorefraction of the right eye.

METHODS

Demographic information including age, sex, and race or ethnicity were collected during the eye examination. Autorefraction was performed before and after cycloplegia. Myopia, defined as at least -0.50 diopter (D) spherical equivalent (SE), hyperopia, defined as at least +0.50 D SE, and astigmatism of at least 1.00 D cylinder were determined using noncycloplegic and cycloplegic autorefractions. Factors associated with at least 1.00 D more myopic SE or at least 0.75 D cylindrical difference by noncycloplegic autorefraction were assessed using logistic regression models.

MAIN OUTCOME MEASURES

Differences between noncycloplegic and cycloplegic autorefraction measurements.

RESULTS

The mean age was 10.8 ± 4.0 years for the 11 119 individuals; 52.4% of participants were female. Noncycloplegic SE measured 0.65 ± 1.04 D more myopic than cycloplegic SE. After adjusting for demographic factors and refractive error, individuals with at least 1.00 D of more myopic SE refraction by noncycloplegic autorefraction (25.9%) were more likely to be younger than 5 years (odds ratio [OR], 1.45; 95% confidence interval [CI], 1.18-1.79) and 5 to younger than 10 years (OR, 1.32; 95% CI, 1.18-1.48) than those 10 to younger than 15 years. This difference of at least 1.00 D of more myopic SE was more likely to be observed in Hispanic people (OR, 1.23; 95% CI, 1.10-1.36) and those with hyperopia (OR range, 4.20-13.31). Individuals with 0.75 D or more of cylindrical difference (5.1%) between refractions were more likely to be younger than 5 years, to be male, and to have mild-moderate-high myopia or moderate-high hyperopia.

CONCLUSIONS

Three quarters of school-aged individuals had < 1 D of myopic SE difference using noncycloplegic compared with cycloplegic autorefraction. Understanding measurement differences obtained for refractive error and associated factors may provide useful information for future studies or programs involving refraction in school-aged children.

Healthcare utilization and economic burden of myopia in urban China: A nationwide cost-of-illness study

Background

China contributes to a significant proportion of the myopia in the world. The study aims to investigate the utilization of various correction methods and health service in urban China, and to estimate the cost of myopia treatment and prevention. In addition, we aimed to estimate the cost of productivity loss due to myopia.

Methods

The study was a cross-sectional investigation carried out in urban areas in three provinces located in the east (Shanghai), middle (Anhui) and west part (Yunnan) of China, in 2016. A total of 23819 people aged between 5 to 50 years were included. Health utilization and the cost of myopia were analyzed from patients’ perspective.

Results

The total number of people with myopia in the urban China was estimated to be 143.6 million. The correction rate was 89.5%, 92.1%, and 92.7% for Anhui, Shanghai, and Yunnan (χ² = 19.5, P < 0.01). Over the recent year, 20.6%, 16.8%, and 28.8% of myopic subjects visited hospital due to myopia, in Anhui, Shanghai and Yunnan. The annual cost of treatment and prevention of myopia was 10.1 billion US dollar (US$, floating from 9.2 to 11.2 billion US$), and the cost per person was 69US$. The annual cost of loss of productivity was estimated to be 6.7 billion US$ for those with mild to moderate visual impairment (floating from 6.1 to 7.4 billion US$), and 9.4 billion US$ (floating from 8.5 to 10.4 billion US$) for those with severe visual impairment to blindness. Therefore, the total economic burden of myopia was estimated as 173.6 billion CNY (26.3 billion US$).

Conclusions

The present study shows that myopia leads to substantial economic burden in China. The loss of productivity caused by myopia is an important part of the disease burden compared to the cost of correction and treatment paid by individuals. Therefore, the focus of myopia prevention and control should be to decrease the myopia prevalence, and prevent the uncorrected refractive errors and the irreversible damage of visual acuity by high myopia.

Systematic review and meta-analysis of myopia prevalence in African school children

Purpose

Increased prevalence of myopia is a major public health challenge worldwide, including in Africa. While previous studies have shown an increasing prevalence in Africa, there is no collective review of evidence on the magnitude of myopia in African school children. Hence, this study reviews the evidence and provides a meta-analysis of the prevalence of myopia in African school children.

Methods

This review was conducted using the 2020 Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) guidelines. Five computerized bibliographic databases, PUBMED, Scopus, Web of Science, ProQuest, and Africa Index Medicus were searched for published studies on the prevalence of myopia in Africa from 1 January 2000 to 18 August 2021. Studies were assessed for methodological quality. Data were gathered by gender, age and refraction technique and standardized to the definition of myopia as refractive error ≥ 0.50 diopter. A meta-analysis was conducted to estimate the prevalence. Significant heterogeneity was detected among the various studies (I² >50%), hence a random effect model was used, and sensitivity analysis was performed to examine the effects of outliers.

Results

We included data from 24 quality assessed studies, covering 36,395 African children. The overall crude prevalence of myopia over the last two decades is 4.7% (95% CI, 3.9–5.7) in African children. Although the prevalence of myopia was slightly higher in females (5.3%, 95%CI: 4.1, 6.5) than in males (3.7%, 95% CI, 2.6–4.7; p = 0.297) and higher in older [12–18 years 5.1% (95% CI, 3.8–6.3) than younger children (aged 5–11 years, 3.4%, 95% CI, 2.5–4.4; p = 0.091), the differences were not significant. There was a significantly lower prevalence of myopia with cycloplegic compared with non-cycloplegic refraction [4.2%, 95%CI: 3.3, 5.1 versus 6.4%, 95%CI: 4.4, 8.4; p = 0.046].

Conclusions

Our results showed that myopia affects about one in twenty African schoolchildren, and it is overestimated in non-cycloplegic refraction. Clinical interventions to reduce the prevalence of myopia in the region should target females, and school children who are aged 12–18 years.

Refractive errors in a large dataset of French children: the ANJO study

Undetected refractive errors (REs) in children can lead to irreversible vision loss. This study aimed to show the proportions of REs in French children using cycloplegic refraction. Multicentre cross-sectional retrospective study including children with cycloplegic refraction and without associated ocular conditions from 2015 to 2018 in French eye clinics. The following data were collected: age, symptoms of eye strain, best-corrected visual acuity (BCVA), cycloplegic refraction. The analysis included 48,163 children (mean age: 7.75 years, range: 2 to 12 years). The proportion of each RE was as follows: emmetropia (− 0.50 < Spherical Equivalent (SE) ≤  + 2.0; 58.3%), hyperopia (+ 2.0 \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$<$$\end{document}< SE \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\le$$\end{document}≤+5; 17.2%), myopia (− 6 \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\le$$\end{document}≤ SE \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\le$$\end{document}≤− 0.50; 15.5%), high myopia (SE < − 6; 0.5%), high hyperopia (SE >  + 5; 3.6%), mixed astigmatism (4.9%). Anisometropia (SE difference ≥ 1.5) was found in 5.0%. Functional amblyopia in children attending primary school (aged over 6 years) was encountered in 2.7%. Symptoms of eye strain were frequent (70%) but not specific to any RE. REs are frequently found in French children and may remain undetected in the absence of symptoms of eye strain. Few studies have investigated REs in children using cycloplegic refraction, which has been shown to be the gold standard for RE assessment.

Pseudomyopia: A Review

This review has identified evidence about pseudomyopia as the result of an increase in ocular refractive power due to an overstimulation of the eye’s accommodative mechanism. It cannot be confused with the term “secondary myopia”, which includes transient myopic shifts caused by lenticular refractive index changes and myopia associated with systemic syndromes. The aim was to synthesize the literature on qualitative evidence about pseudomyopia in terms that clarify its pathophysiology, clinical presentation, assessment and diagnosis and treatment. A comprehensive literature search of PubMed and the Scopus database was carried out for articles published up to November 2021, without a data limit. This review was reported following the preferred reporting items for systematic reviews and meta-analyses (PRISMA) guidelines. Following inclusion and exclusion criteria, a total of 54 studies were included in the qualitative synthesis. The terms pseudomyopia and accommodation spasm have been found in most of the studies reviewed. The review has warned that although there is agreement on the assessment and diagnosis of the condition, there is no consensus on its management, and the literature describes a range of treatment.

Physical activity, time spent outdoors, and near work in relation to myopia prevalence, incidence, and progression: An overview of systematic reviews and meta-analyses

Myopia has reached epidemic levels in recent years. Stopping the development and progression of myopia is critical, as high myopia is a major cause of blindness worldwide. This overview aims at finding the association of time spent outdoors (TSO), near work (NW), and physical activity (PA) with the incidence, prevalence, and progression of myopia in children. Literature search was conducted in PubMed, Scopus, Cumulative Index to Nursing and Allied Health Literature, Cochrane Database of Systematic Reviews, ProQuest, and Web of Science databases. Systematic reviews (SR) and meta-analyses (MA) on the TSO, NW, and PA in relation to myopia were reviewed. Methodological nature of qualified studies were evaluated utilizing the Risk of Bias in Systematic Review tool. We identified four SRs out of which three had MA, which included 62 unique studies, involving >1,00,000 children. This overview found a protective trend toward TSO with a pooled odds ratio (OR) of 0.982 (95% confidence interval (CI) 0.979-0.985, I2 = 93.5%, P < 0.001) per extra hour of TSO every week. A pooled OR 1.14 (95% CI 1.08-1.20) suggested NW to be related to risk of myopia. However, studies associating myopia with NW activities are not necessarily a causality as the effect of myopia might force children to indoor confinement with more NW and less TSO. PA presented no effect on myopia. Though the strength of evidence is less because of high heterogeneity and lack of clinical trials with clear definition, increased TSO and reduced NW are protective against myopia development among nonmyopes.

The Refractive Error and Vision Impairment Estimation with Spectacle Data Study

Purpose

To investigate whether spectacle lens sales data can be used to estimate the population distribution of refractive error among patients with ametropia and hence to estimate the current and future risk of vision impairment.

Design

Cross-sectional study.

Participants

A total of 141 547 436 spectacle lens sales records from an international European lens manufacturer between 1998 and 2016.

Methods

Anonymized patient spectacle lens sales data, including refractive error information, was provided by a major European spectacle lens manufacturer. Data from the Gutenberg Health Survey was digitized to allow comparison of a representative, population-based sample with the spectacle lens sales data. A bootstrap analysis was completed to assess the comparability of both datasets. The expected level of vision impairment resulting from myopia at 75 years of age was calculated for both datasets using a previously published risk estimation equation combined with a saturation function.

Main Outcome Measures

Comparability of spectacle lens sales data on refractive error with typical population surveys of refractive error and its potential usefulness to predict vision impairment resulting from refractive error.

Results

Equivalent estimates of the population distribution of spherical equivalent refraction can be provided from spectacle lens data within limits. For myopia, the population distribution was equivalent to the Gutenberg Health Survey (≤ 5% deviation) for levels of –2.0 diopters (D) or less, whereas for hyperopia, the distribution was equivalent (≤ 5% deviation) for levels of +3.0 D or more. The estimated rates of vision impairment resulting from myopia were not statistically significantly different (chi-square, 182; degrees of freedom, 169; P = 0.234) between the spectacle lens dataset and Gutenberg Health Survey dataset.

Conclusions

The distribution of refractive error and hence the risk of vision impairment resulting from refractive error within a population can be determined using spectacle lens sales data. Pooling this type of data from multiple industry sources could provide a cost-effective, timely, and globally representative mechanism for monitoring the evolving epidemiologic features of refractive error and associated vision impairment.

The Impact of Hyperopia on Academic Performance Among Children: A Systematic Review

PURPOSE

To assess the impact of uncorrected hyperopia and hyperopic spectacle correction on children's academic performance.

DESIGN

Systematic review and meta-analysis.

METHODS

We searched 9 electronic databases from inception to July 26, 2021, for studies assessing associations between hyperopia and academic performance. There were no restrictions on language, publication date, or geographic location. A quality checklist was applied. Random-effects models estimated pooled effect size as a standardized mean difference (SMD) in 4 outcome domains: cognitive skills, educational performance, reading skills, and reading speed. (PROSPERO registration: CRD-42021268972).

RESULTS

Twenty-five studies (21 observational and 4 interventional) out of 3415 met the inclusion criteria. No full-scale randomized trials were identified. Meta-analyses of the 5 studies revealed a small but significant adverse effect on educational performance in uncorrected hyperopic compared to emmetropic children {SMD -0.18 [95% confidence interval (CI), -0.27 to -0.09]; P < 0.001, 4 studies} and a moderate negative effect on reading skills in uncorrected hyperopic compared to emmetropic children [SMD -0.46 (95% CI, -0.90 to -0.03); P = 0.036, 3 studies]. Reading skills were significantly worse in hyperopic than myopic children [SMD -0.29 (95% CI, -0.43 to -0.15); P < 0.001, 1 study]. Qualitative analysis on 10 (52.6%) of 19 studies excluded from meta-analysis found a significant (P < 0.05) association between uncorrected hyperopia and impaired academic performance. Two interventional studies found hyperopic spectacle correction significantly improved reading speed (P < 0.05).

CONCLUSIONS

Evidence indicates that uncorrected hyperopia is associated with poor academic performance. Given the limitations of current methodologies, further research is needed to evaluate the impact on academic performance of providing hyperopic correction.

China Turns to School Reform to Control the Myopia Epidemic: A Narrative Review

ABSTRACT

Myopia is now a major public health issue in parts of East and Southeast Asia, including mainland China. In this region, around 80% of students completing 12 years of school education are now myopic, and from 10% to 20% have high myopia in excess of -6D. Interventions to prevent the onset of myopia based on increasing time outdoors have now been implemented at a system-wide scale in Chinese Taipei (Taiwan) and Singapore with some success, but the prevalence of myopia still remains high by international standards. In mainland China, until recently, myopia prevention was largely based on eye exercises, but these have not been sufficient to prevent an epidemic. Control of myopia progression with atropine eye drops has been widely practiced in Singapore and Taiwan, with recent practice concentrating on low-dose concentrations. Orthokeratology has also been widely used across the region. Recent research has produced both contact and spectacle lenses that slow myopia progression by imposing myopic defocus. The new approaches to myopia control are ready for systematic use, which may be facilitated by system-wide screening and referral. In recent years, renewed emphasis has been placed on the prevention of myopia in mainland China by China's President Xi Jinping. In addition to making use of all the measures outlined above, China now seems to be aiming for major reforms to schooling, reducing educational pressures, particularly in the early school years, freeing more time for outdoor play and learning. These new initiatives may be crucial to myopia prevention and control.