Comparison of the refractive measurements with hand-held autorefractometer, table-mounted autorefractometer and cycloplegic retinoscopy in children

Retinoscopes: Past and present

BACKGROUND

Retinoscopy is arguably the most important method in the eye clinic for diagnosing and managing refractive errors. Advantages of retinoscopy include its non-invasive nature, ability to assess patients of all ages, and usefulness in patients with limited cooperation or communication skills.

AIM

To discuss the history of retinoscopes and examine current literature on the subject.

METHODS

A search was conducted on the PubMed and with the reference citation analysis (https://www.referencecitationanalysis.com) database using the term “Retinoscopy,” with a range restricted to the last 10 years (2013-2023). The search string algorithm was: "Retinoscopy" (MeSH Terms) OR "Retinoscopy" (All Fields) OR "Retinoscopes" (All Fields) AND [(All Fields) AND 2013: 2023 (pdat)].

RESULTS

This systematic review included a total of 286 records. Publications reviewed iterations of the retinoscope into autorefractors, infrared photo retinoscope, television retinoscopy, and the Wifi enabled digital retinoscope.

CONCLUSION

The retinoscope has evolved significantly since its discovery, with a significant improvement in its diagnostic capabilities. While it has advantages such as non-invasiveness and broad applicability, limitations exist, and the need for skilled interpretation remains. With ongoing research, including the integration of artificial intelligence, retinoscopy is expected to continue advancing and playing a vital role in eye care.

Efficacy of 3D-printed eye model to enhance retinoscopy skills

We conducted a prospective study to evaluate the efficacy of simulation-based education using a three-dimensional (3D)-printed schematic eye model in improving the retinoscopy refraction skills of medical students. A schematic eye model was printed using a fused deposition modeling-based 3D printer. Twenty medical students randomized into 3D (n = 10) and control (n = 10) groups received a 1-h lecture on the principles and methods of manifest refraction and were shown how to use the retinoscope and sciascope bars. The 3D group additionally attended a tutorial on the schematic eye. Both groups performed refractive examinations on four eyes of volunteer patients, and the results were recorded as a baseline. Instructor feedback and refraction practice was provided with the 3D group or with control group. To account for subject fatigue, patients spent no more than 8 min on the examination. After a 1-h break to allow for fatigue and familiarity, refraction tests were repeated on four randomly selected eyes of patients. Students' refraction readings were compared with the autorefractor values using a spherical equivalent value and blur strength. All participants measured the time required to complete the refraction test and reported their subjective confidence in the results of each refraction test. Refractive errors before and after training did not differ between the control and 3D groups, with a significant improvement in errors observed in both groups (p = 0.005 and 0.008, respectively). The time to complete refraction before and after training did not differ between the two groups, both of which showed a significant reduction in time (p = 0.005 and 0.028, respectively). Pre- and post-training confidence scores for the accuracy of each refraction on a 10-point Likert scale were not significantly different. However, when comparing score changes between pre- and post-training, only the control group showed a significant increase in confidence (p = 0.005). Tests for the non-inferiority of refractive errors after training indicated that the 3D group was non-inferior to the control group. In conclusion, training in retinoscopy refraction skills using a 3D-printed eye model resulted in significant improvement in accuracy and speed compared to practice with real patients. Except for better confidence in the control group, schematic eye model training was not inferior to practice with real patients.

Training in retinoscopy: learning curves using a standardized method

BACKGROUND

Retinoscopy is one of the most effective objective techniques for evaluating refractive status, especially in non-cooperative patients. However, it presents a slow learning curve that often leads to student frustration. With the current Covid-19 pandemic and the need for social isolation, clinical education based on simulation has become more relevant. Therefore, we implemented retinoscopy laboratories and learning protocols to reduce student stress and learning time.

METHODS

We conducted a study to evaluate the retinoscopy learning curve using a new training protocol proposal. One hundred trainees were assessed in four stages, corresponding to 08, 12, 16, and 20 hours of training. Six different refractive defects were used trying to reproduce frequent conditions of care. The time spent on the assessment was not considered as additional training time. To analyze the data, we used non-parametric statistics and linear regression to assess the variables associated with training time and performance rate.

RESULTS

The mean performance score at 08 hrs was 32.49% (±16.69 SD); at 12 hrs was 59.75% (±18.80 SD); at 16 hrs was 70.83% (±18.53 SD) and at 20 hrs was 84.26% (±13.18 SD). Performance at 12 hrs was significative higher than 08 hrs of training, but did not show significant differences with the performance rate at 16 and 20 hrs. We found a strong positive correlation between performance and training time in retinoscopy (R = 0.9773, CI: 0.2678 - 0.9995 p = 0.0227).

CONCLUSION

This study showed that an increasing number of hours of practice positively correlates with performance in retinoscopy. The elaboration of a protocol and standardization of performance per hour also allowed us to estimate that a minimum of 13.4 hrs of practice is required to achieve 60% performance. Using the resulting formula, it is possible to determine the number of hours of retinoscopy practice are necessary to reach a certain level of performance.

Comparability of the Retinomax K-plus 3 handheld autorefractometer in quick mode versus on-table autorefractometer in standard mode

INTRODUCTION

This study analyzes the comparability of measurements taken by a Retinomax K-plus 3 handheld autorefractometer in Quick mode and a Topcon KR-800 on-table autorefractometer in standard mode on the pediatric population, and establishes their correlation.

METHODS

It is a retrospective comparative study. Spherical diopter power (SPH), cylindrical diopter power (CYL), angle of cylindrical axis (AX), and spherical equivalent (SE) were measured with the Retinomax in Quick mode and with the Topcon in standard mode. Each patient was evaluated in cycloplegic and non-cycloplegic conditions by both autorefractometers. Student's t-test was performed between the two instruments for SPH, CYL, and SE. The Pearson correlation coefficient was calculated and the dispersion was represented using Bland-Altman graphs, also evaluating the subgroup of patients under 4 years of age. A descriptive analysis of the percentages of measures that differed was performed.

RESULTS

It included 98 eyes of 49 subjects (age range: 3-16 years). The data for HPS without cycloplegia are virtually identical, whereas with cycloplegia there is a hyperopic bias of +0.5 diopters measured with Retinomax. CYL results are very similar with and without cycloplegia. There is a high Pearson correlation for both instruments (>0.91) and a low degree of dispersion in the Bland-Altman plots under cycloplegia.

CONCLUSION

The Retinomax data were consistent with those obtained by Topcon. The Retinomax is a useful instrument for detecting refractive errors in children between 3 and 16 years of age.

Automated and subjective refraction with monofocal, multifocal, and EDOF intraocular lenses: review

Automated refraction (Scheiner principle) is universally used to start a visual examination. Although the results are reliable in eyes implanted with monofocal intraocular lenses (IOLs), they may be less precise with multifocal (mIOL) or extended depth-of-focus (EDOF) IOLs and can even indicate a refractive error that does not clinically exist. Autorefractor results with monofocal, multifocal, and EDOF IOLs were investigated through literature search analyzing the papers reporting the difference between automated and clinical refraction. The average difference ranged between -0.50 diopter (D) and -1.00 D with most mIOL and EDOF IOLs. The differences in astigmatism were generally much lower. Autorefractors using infrared light cannot measure eyes with high technology IOLs precisely because of the influence of the refractive or of the diffractive near add. The systematic error induced with some IOLs should be mentioned in the IOL label to prevent possible inappropriate refractive procedures to treat apparent myopia.

Rise of the Machines? Comparison of Cycloplegic Refraction Using Retinoscopy and the Retinomax K-Plus 5 in Children

PURPOSE

To compare the ability to detect refractive anomalies in children using automated refraction versus retinoscopic cycloplegic refraction.

METHODS

A pediatric population from a pediatric eye institute underwent complete ophthalmic examinations. Children were randomly assigned to one of two pediatric optometrists who performed manual cycloplegic refraction using retinoscopy and automated cycloplegic refraction using a handheld autorefractometer (Retinomax K-plus 5; Right Mfg. Co., Ltd.). Recorded patient data included refraction values for each eye (sphere, astigmatism, and axis), use of glasses, and degree of cooperation.

RESULTS

Two hundred thirteen children were included. The mean age was 6.2 years. For all ages, strong associations were found in sphere and spherical equivalent (SE) measurements between the two methods (b = 0.78, P < .001; b = 0.71, P < .001; respectively). Among children older than 5 years, associations between the two methods were significant in all parameters (sphere: b = 0.99, P < .001; astigmatism: b = 0.69, P < .001; axis: b = 0.19, P < .05; SE: b = 0.97, P < .001), whereas among children 5 years and younger, a significant association was found only in the axis measurements (b = 0.31, P < .01). Retinomax K-plus 5 measurements showed significantly more hyperopic results in sphere measurements and higher astigmatism in all children examined, but this difference was markedly higher in children 5 years and younger. Good cooperation was observed in 94.1% of children older than 5 years and 77% of children 5 years and younger (P < .001).

CONCLUSIONS

The Retinomax K-plus 5 may be used for screening in children older than 5 years. However, in all age groups, it may not be accurate enough for treatment and decision making, even with good cooperation. [J Pediatr Ophthalmol Strabismus. 2022;59(6):380-387.].

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.

Non-Cycloplegic and Cycloplegic Autorefraction with Retinomax: An Agreement Study in Preschoolers in Los Angeles, California

PURPOSE

To evaluate the agreement between non-cycloplegic autorefraction (NCAR) and cycloplegic autorefraction (CAR) in an ethnically diverse population of preschool-aged children and the validity of the screening criteria used to refer for further evaluation.

METHODS

This study included data from 7,073 preschoolers who underwent NCAR and CAR, which enabled refractive error classification based on the American Association for Pediatric Ophthalmology and Strabismus (AAPOS) 2013 criteria. Right eye data of sphere and cylinder were used to compare NCAR to CAR via paired t-testing and vector analyses, and left eye data for an analysis on anisometropia. The sensitivity and specificity of screening referral criteria for refractive error were calculated.

RESULTS

Mean values of sphere differed between NCAR and CAR by 1.95 ± 1.45 D (p < .05) with 95% limits of agreement (LoA) of -0.94 to 4.85 D, with less discrepancy found in myopic eyes. The mean values of cylinder differed by -0.08 ± 0.43 D (p < .05) with 95% LoA of -0.93 to 0.77 D. Power vector results reflected a similar lack of agreement. The sensitivity and specificity of our screening referral criteria were, respectively, 66% and 84% for myopia, 66% and 98% for hyperopia, and 98% and 58% for astigmatism.

CONCLUSION

NCAR is insufficient in preschoolers for spherical refractive error referrals. Level of agreements was lower for spherical (15.5% within 0.5D) and higher for cylindrical refractive errors (89.6%) compared to CAR. In the absence of cycloplegic examination, screening programs using NCAR should utilize low referral thresholds for spherical refractive error.

Neutral Density Filters as a Tool for Cycloplegic Plusoptix-Photorefractor Measurements: An Explorative Study

Purpose:

The purpose of this study is to investigate the usefulness of neutral-density (ND) filters in cycloplegic-Plusoptix-photorefractor measurements.

Methods:

No-filter and ND-filter 0.04, 0.1 and 0.2 cycloplegic-Plusoptix-photorefractor measurements were made in 42 hypermetropic eyes. Sphere, cylinder, spherical equivalent (SEQ), J0, and J45 values were compared.

Results:

Mean Plusoptix-photorefractor pupil sizes were 7.7±0.68 and 7.7±0.72 mm The no-filter failure rate was 16%, with 87% in pupils >7.8 mm. Mean no-filter sphere, cylinder, SEQ, J0 and J45 values were +0.34±0.35D, -0.29±0.22D, +0.20±0.36, -0.00±0.15, and +0.02±0.11, respectively. Only ND-filter-0.04 provided 5% more successful measurements and a clinically significant alteration in the percentage of values exceeding 0.5D for sphere and SEQ (-10% and -20%), but not for cylinder (+5%). Despite the increased accuracy, 21% of the spherical outcome exceeded 0.50D. Furthermore, the single-measure-intraclass-correlation-coefficient between no-filter and ND-filter-0.04 outcome was moderate (sphere 0.78 (0.62-0.87), cylinder 0.59 (0.35-0.75), SEQ 0.68 (0.48-0.82), J0 0.73 (0.54-0.84) and J45 0.57 (0.50-0.86)) and indicated significant individual variation. Bland-Altman-analyses indicated significant bias for sphere and SEQ; p=0.038 and p=0.030.

Conclusion:

ND-filter-0.04 resulted in a larger proportion of successful measurements and an increased accuracy. However, an unacceptable percentage of inaccuracy was still present compared to retinoscopy. There could be validity issues with the ND-filter 0.04 or the baseline no-filter readings at the start. We conclude that cycloplegic Plusoptix-photorefraction, even with the use of a 0.04 ND filter, is not a suitable method for exact objective refraction purposes in children.

Learning retinoscopy: A journey through problem space

PURPOSE

Retinoscopy is a skill that requires the integration of procedural skill and declarative knowledge. Whilst the actual technique is simple, retinoscopy is a complex skill to acquire and is one that students often find challenging. This study compared the strategies that novices, third-year students and experts use when performing retinoscopy, with the aim of identifying the key stages of learning that may enlighten teaching practice.

METHOD

This study employed a protocol-based approach in which the verbal protocols and cognitive strategies of novices, students and experts were recorded and then subjected to 'problem space' analysis.

RESULTS

Clear differences existed when the retinoscopy of novices, students and experts was directly compared using a standardised simulated task. Experts were more accurate in performance and used defined strategies to reach the goal. The presence of these strategies significantly predicted the accuracy of the retinoscopy result.

CONCLUSION

This study highlights the importance of meta-cognitive strategies and the need for an adequate theoretical foundation in skill acquisition. The underpinning knowledge provides a pedagogic tool that specifies activities which are beneficial to learning a clinical skill.

Comparison of the results of four different refraction measurement devices in children with retinoscopy

Purpose: The purpose of this study was to compare the results of 4 different autorefractometer devices with the results of retinoscopy in children. Methods: A total of 120 eyes of 60 patients aged between 6 and 18, who applied to Afyonkarahisar Health Sciences University unit of Pediatric Ophthalmology, were included in the study. Refraction with Plusoptix A09 (photoscreener) without cycloplegia was the first to be measured. Spherical and cylindrical values were recorded. Then, half an hour after the patients were instilled 2 drops of cyclopentolate with an interval of 5 minutes, dilated retinoscopy was performed, and spherical and cylindrical values were recorded. Autorefractometer measurements with cycloplegia were performed with Canon RK-F1 autorefractometer, Nidek Tonoref III and Retinomax K-Plus 3, and spherical and cylindrical values were recorded. Results: The mean age of the patients was 11.02 ± 2.1. The mean spherical equivalents were Canon RKF1 autorefractometer +0.045 ± 2.49, Nidek TonoRef III +0.023 ± 2.48, Retinomax K-Plus 3 +0.078 ± 1.42, Plusoptix A09 -0.119 ± 2.20, retinoscopy +0.124 ± 2.65. Moreover, the mean cylindrical values were Canon RK-F1 autorefractometer -0.893 ± 0.69, Nidek TonoRef III -0.927 ± 0.72, Retinomax K-Plus 3 -0.888 ± 0.73, Plusoptix A09 -0.883 ± 0.719, retinoscopy -0.923 ± 0.71. The statistical values compared with retinoscopy; Canon RKF1 spherical equivalent (p=0.376), cylindrical (p=0.515), Nidek TonoRef III spherical equivalent (p=0.485), cylindrical (p=0.198), Retinomax K-Plus 3 spherical equivalent (p=0.141), cylindrical (p=0.058), Plusoptix A09 spherical equivalent (p=0.085) and cylindrical (p=0.086) values were not different. Conclusions: In spherical and cylindrical refractive error detection, all 4 devices showed reasonable and consistent results compared to retinoscopy.

Refractive outcomes of table-mounted and hand-held auto-refractometers in children: an observational cross-sectional study

BACKGROUND

To compare the refractive results of hand-held and table-mounted autorefractors.

METHODS

We designed this study as an observational, cross-sectional study. We compared the mean spheric and cylinder power, spherical equivalent, Jackson cross-cylinder values, determined the limits of agreement (LoA), and evaluated the reliability of two autorefractors.

RESULTS

We evaluated 256 eyes of 256 pediatric patients (mean age, 9.12 ± 2.26 years; range, 5-16 years). 49% of the patients were female, and 51% were male. The Nidek HandyRef-K autorefractor measured relatively more astigmatism (P < 0.001) and less hyperopia (P = 0.024). The mean differences and 95% LoA were 0.06 D ± 0.47 D (- 0.82 D to 0.98 D) in spherical power, 0.08 D ± 0.28 D (- 0.47 D to 0.64 D) in cylindrical power, 0.11 D ± 0.47 D (- 0.81 D to 1.01 D) in spherical equivalent, 0.02 D ± 0.36 D (- 0.73 D to 0.69 D) in Jackson cross-cylinder power at 0°, 0.005 D ± 0.54 D (- 1.07 D to 1.06 D) in Jackson cross-cylinder power at 45°. We found the difference within 0.50 D in 244 (95%) eyes for spherical power, in 245 (96%) eyes for cylindrical power, 228 (89%) eyes for spherical equivalent, 224 (87%) eyes for Jackson cross-cylinder power at 0°, 213 (83%) eyes for Jackson cross-cylinder power at 45°. When comparing devices, there were strong correlations for spherical power (Spearman's rho = 0.99, P < 0.001), cylindrical power (Spearman's rho = 0.88, P < 0.001), and spherical equivalent (Spearman's rho = 0.98, P < 0.001).

CONCLUSION

Two autorefractors showed clinically applicable agreement limits; excellent reliability for spherical power and spherical equivalent and good reliability for cylindrical power; high positive percent agreement for spherical and cylindrical power, spherical equivalent, Jackson cross-cylinder power at 0°and 45°. These results showed that both devices might be used interchangeably for screening of refractive error in children.

Reliability of Refraction, Keratometry, and Intraocular Pressure Measurements with an Automated All-in-one Device

SIGNIFICANCE

This study explores the reliability of TonoRef II (Nidek, Tokyo, Japan), which represents a simple tool to obtain rapid refractometry and tonometry measurements. The present device demonstrates very high repeatability of refraction and intraocular pressure (IOP) readings as compared with subjective measurements and a higher concordance of IOP readings to Goldmann application tonometry (GAT).

PURPOSE

This study aimed to evaluate the repeatability of measurements acquired with the Autorefractometer/Keratometer/Tonometer TonoRef II and assess their agreement to subjective measurements and readings of other established devices.

METHODS

In a cross-sectional study, 54 eyes of 54 healthy subjects were enrolled. Each subject underwent five measurements with the TonoRef II, three measurements with the Canon RK-F1 Autorefractor Keratometer (Canon Europe NV, Amstelveen, the Netherlands), three IOP measurements with the Canon TX-F Noncontact Tonometer (Canon Inc., Tokyo, Japan), three measurements with GAT, and a thorough subjective refraction. Repeatability coefficient (r), intraclass correlation coefficient (ICC), and Bland-Altman plots were used to evaluate repeatability of readings and agreement to the subjective values.

RESULTS

TonoRef II showed high repeatability (ICC >0.9) in all parameters tested (sphere, r = 0.157; cylinder, r = 0.196; IOP, r = 2.653). A strong correlation was found between TonoRef and Canon instruments (P < .001 in all parameters). Mean differences and limits of agreement (mean ± 1.96 standard deviation) were -0.01 ± 0.69 D, -0.11 ± 0.7 D, and 2.1 ± 3.4 mmHg for sphere, cylinder, and IOP, respectively. Both autorefractors achieved a very good to excellent agreement to the values obtained with the subjective refraction for most of the parameters tested, without any significant difference to each other (P > .05). Intraocular pressure measurements of TonoRef II showed higher agreement to the GAT values compared with those obtained with the Canon tonometer (ICC, 0.9114 and 0.7002, respectively; P < .001).

CONCLUSIONS

Intraocular pressure and refraction readings acquired with TonoRef II demonstrate very high repeatability and agreement to the subjective measurements. Regarding IOP evaluation, TonoRef II shows higher concordance to GAT compared with another established noncontact tonometer.

Preterm refraction and ocular biometry in children with and without retinopathy of prematurity in the first year of life

PURPOSE

To determine ocular biometric and refractive profiles of premature children at risk of retinopathy of prematurity (ROP), comparing those who did and did not require laser treatment.

METHODS

In this prospective study, premature infants underwent biometry and refraction with their first ROP examination. Study parameters were assessed again at 3 months, 6 months, and 1 year. The main outcome measures were spherical equivalent, axial length, and keratometry.

RESULTS

A total of 122 infants (243 eyes) were included. At baseline, infants without ROP, those with ROP who never needed treatment, and those who later needed treatment had overall comparable axial length (P = 0.53) and myopia (P = 0.05); the highest severity group had higher corneal steepness and more myopia at baseline. At 1 year, children with laser-treated ROP had the shortest axial lengths, with the least decrease in keratometry, and the greatest increase in myopia (-2.0 D; P = 0.001). Anisometropia, if present initially, persisted through the 1-year examination. Mean refractive error was more myopic in zone 1 disease (P = 0.3) and in aggressive posterior ROP (P = 0.15).

CONCLUSIONS

Severe ROP is associated with disruption of emmetropization, and steeper corneas and more myopia at the first ROP examination, before any intervention. In our study cohort, these differences became more marked over the course of 1 year after laser therapy. The myopia in these cases was not axial. Laser therapy did not induce new anisometropia.

The biometric parameters of aniso-astigmatism and its risk factor in Chinese preschool children: the Nanjing eye study

Backgrounds

Aniso-astigmatism may hinder normal visual development in preschool children. Knowing its prevalence, biometric parameters and risk factors is fundamental to children eye care. The purpose of this study was to determine the biometric components of aniso-astigmatism and associated maternal risk factors in Chinese preschool children.

Methods

In the population-based, prospective cohort Nanjing Eye Study, children were measured for noncycloplegic refractive error using an autorefractor and for biometric parameters using an optical low-coherent reflectometry. The difference of total astigmatism (TA) between both eyes was calculated using cylinder power (non-vectorial aniso-TA was defined as ≥1.00 Dioptre Cylinder [DC] between both eyes) and by vector analysis (vectorial aniso-TA was defined as a difference of ≥0.5 in J₀ or J₄₅ between both eyes which is equivalent to 1.00 DC). The prevalence of aniso-TA was presented. Interocular biometric parameters were compared between with vs. without aniso-astigmatism group. In addition, risk factors were determined using multivariate logistic regression model.

Results

Of 1131 children (66.90 ± 3.38 months, 53.31% male), the prevalence of non-vectorial aniso-TA was 1.95% (95% Confidence Interval (CI) = 1.14–2.75%), while the prevalence of vectorial aniso-TA was twice as common as non-vectorial aniso-TA, neither varying with sex or age. With aniso-TA eyes were more asymmetric in axial length and corneal curvature radius than without aniso-TA eyes. In multivariate logistic regression model, 5-min Apgar score less than 7 was significantly associated with higher risk of aniso-TA (vectorial aniso-TA: Odds Ratio (OR) = 6.42, 95%CI = 2.63–15.69, P < 0.001; non-vectorial aniso-TA: OR = 4.99, 95%CI = 1.41–17.68, P = 0.01). Being twin or triple was significantly associated with higher risk of vectorial aniso-CA (OR = 2.43, 95%CI = 1.05–5.60, P = 0.04). Pre-term delivery (OR = 2.60, 95%CI = 1.09–6.15, P = 0.03) and post-term delivery (OR = 3.61, 95%CI = 1.31–9.96, P = 0.01) were significantly associated with higher risk of vectorial aniso-CA.

Conclusions

Both corneal curvature radius and axial length asymmetry were correlated with aniso-TA. Children with 5-min Apgar score < 7 were more likely to have aniso-TA, while twin or triple, pre-term or post-term delivery were more likely to have vectorial aniso-CA.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12886-021-01808-7.

Are the results of handheld auto-refractometer as valid as the result of table-mounted refractometer?

Purpose

To determine the agreement of table-mounted and handheld auto-refractometers and to evaluate the effect of age and different types of refractive errors on this comparison.

Methods

In this cross-sectional study conducted in 2015 using multi-stage cluster sampling, two underserved villages were selected randomly in the north and southwest of Iran. All the selected participants underwent optometric and ophthalmic examinations. Refraction was measured using handheld and table-mounted auto-refractometers in 652 subjects.

Results

The mean age of the subjects was 32.7 ± 18.72 years, and 58.3% of them were female. A significant difference was observed in the results of sphere, spherical equivalent (SE), and J45 vector between the two devices (P < 0.012), but there was no significant difference in J0 vector. There was a significant difference in the results of sphere between the two devices in all age groups under 50 years (P = 0.005), but there was no difference in age groups above 50 years. Correlation coefficients of the two devices were 0.989, 0.986, 0.908, and 0.951 for the results of sphere, SE, J0 vector, and J45 vector, respectively (P < 0.0001). The 95% limit of agreement (LOA) of the two devices was -0.31 to +0.53 for sphere, -0.27 to +0.63 for SE, -0.27 to +0.27 for J0 vector, and -0.16 to -0.17 for J45 vector.

Conclusions

According to our findings, the spherical error and cylindrical power measurements of the two devices have a significant correlation. Although there is a significant difference in the mean values between the two devices, this difference may be considered clinically insignificant, and considering the narrow 95% LOA between the two devices, the results may be used interchangeably.

[Amblyopia-Basic principles and current diagnostic and therapeutic standards]

Amblyopia is a visual deficit that occurs during childhood and results in an abnormal development of the normal cortical visual pathway. It is defined as the reduction of best corrected visual acuity of one or rarely both eyes, which is not explained by structural abnormalities of the eye alone. During the sensitive period amblyopia is completely or partially reversible. The main causes of amblyopia are strabismus and refractive errors. Congenital cataracts are less common but if present may cause pronounced amblyopia. In Germany the prevalence of Amblyopia is approximately 5%, which is relatively high in relation to other countries, even though data are not completely comparable. As amblyopia can only be successfully treated during the first years of life, early detection of amblyogenic factors is important. Screening tests help in identifying children at risk of amblyopia, while only a thorough ophthalmological examination including cycloplegic refraction reliably detects all risk factors of amblyopia. Treatment consists of removal of the amblyogenic factors and stimulation of the amblyopic eye.

A Comparison of Three Different Photoscreeners in Children

PURPOSE

To compare the results obtained from three non-cycloplegic handheld photorefractometers with cycloplegic autorefractometry (Topcon KR-8100; Topcon Corporation, Tokyo, Japan) measurement in children.

METHODS

The refractive status of 238 eyes in 119 healthy children was assessed. The values acquired using photorefraction with the non-cycloplegic PlusoptiX A12 (Plusoptix GmbH, Nuremberg, Germany), Retinomax K-plus 3 (Righton, Tokyo, Japan), and Spot Vision Screener (Welch Allyn, Skaneateles Falls, NY) devices were compared with those obtained from the cycloplegic Topcon KR-8100. The agreement between the measurements was assessed using the intraclass correlation coefficient.

RESULTS

The mean age was 10.1 ± 3.2 years (range: 6 to 17 years). The mean spherical value for the right eyes was 0.38 diopters (D) (range: -4.50 to 6.25 D) for the Plusoptix A12; 0.45 D (range: -4.50 to 6.25 D) for the Spot Vision Screener; -1.15 D (range: -8.75 to 6.50 D) for the Retinomax K-plus 3; and 0.62 (range: -4.50 to 6.00) for the Topcon KR-8100. The mean spherical equivalent value for the right eyes was 0.41 D (range: -4.50 to 7.90 D) for the Plusoptix A12; 0.18 D (range: -4.75 to 6.13 D) for the Spot Vision Screener; -1.30 D (range: -10.50 to 6.38 D) for the Retinomax K-plus 3; and 0.67 D (range: -4.00 to 6.00 D) for the Topcon KR-8100 (for the right eyes).

CONCLUSIONS

The photorefractometer method was beneficial in the measurement of refractive errors of school-aged children. The PlusoptiX A12 photorefractometer method may eliminate the need for cycloplegia in the detection of refractive errors in children. [J Pediatr Ophthalmol Strabismus. 2018;55(5):306-311.].