Hyperopic Refractive Error Research Articles

The Gobi Desert Children Eye Study

Background: To summarize the design and findings of the Gobi Desert Children Eye Study. Methods: The Gobi Desert Children Eye Study is a school-based cohort study. The baseline study was carried out in 2013, with 1,565 out of 1,911 eligible (81.9%) children with a mean age of 11.9±3.5 years (range: 6–21 years) as participants. The study was repeated in 2016 with 958 out of 1,334 eligible children (71.8%, or 61.2% of original participants) with a baseline mean age of 10.3±2.7 years (range: 6–16 years) participated. The participants completed a structured questionnaire and underwent comprehensive ocular examinations including cycloplegic refractometry, pneumotonometry, slit-lamp assisted biomicroscopy, fundus photography and optical coherence tomography. Results: The mean refractive error at baseline in the worse eye was −1.38 diopter (D). In multivariate analysis, more myopic refractive errors were associated with older age (P<0.001; regression coefficient B: −0.26), female gender (P=0.005; B: −0.26), more myopic paternal refractive errors (P<0.001;B: 0.20), more myopic maternal refractive errors (P<0.001; B: 0.18) and fewer hours spent outdoors (P=0.038; B: 0.18). The prevalence of myopia, defined as refractive errors (spherical equivalent) of ≤−0.50 D in the worse eye was 60.0%±1.2%. The prevalence of high myopia (≤−6.00 D) was 2.9%±0.4% in the whole study population, and it was 9.9%±3.0% in 17-year-old. It was not associated with time spent outdoors (P=0.66). The 3-year cumulative incidence of myopia, defined as newly developed refractive error (spherical equivalent) of ≤−0.50 D and ≤−6.00 D in the worse eye during the 3-year follow-up period, was 52.6% and 4.5%, respectively. The mean change of refractive error from baseline was −0.77 and −0.71 D for the right and left eye respectively. The progression of myopia more than −1 diopter happened in 51.0% of participants with baseline myopia ≤−0.50 D. The incidence of myopia (≤−1.00 D) significantly increased with older age (P<0.001; B: 1.14), fewer outdoor activity hours (P=0.07, B: 0.66), higher body height (P=0.002, B: 1.02), more myopic paternal refractive error (P<0.02;B: 0.82), but was not significantly associated with gender (P=0.76), ethnicity (P=0.36), baseline intraocular pressure (P=0.86) and choroidal thickness (P=0.19). The mean subfoveal choroidal thickness (SFCT) was 282±49 µm. In multivariate analysis, thicker SFCT was associated (regression coefficient r: 0.38) with higher hyperopic refractive error (P<0.001; B: 0.31), younger age (P<0.001; B: −0.10), male gender (P=0.03; B: −0.05), higher corneal refractive power (P<0.001; B: 0.12), and non-Han Chinese ethnicity (P=0.03; B: 0.05). Conclusions: Even in Western China, prevalence and incidence of myopia in school children is high. As in East China, low and medium myopia was associated with less time spent outdoors. High myopia was not significantly associated with outdoor time. The relatively high myopia prevalence in school children in China predicts a marked increase in vision-threatening high myopia in future elderly populations in China.

Prevalence and associated factors of strabismus in former preterm and full-term infants between 4 and 10\xa0Years of age

BackgroundLimited data exist collating most of the associated factors for strabismus in one analysis. The aim of this study was to assess the prevalence of strabismus and to analyse associated factors in former preterm and full-term infants.MethodsIn this cross-sectional study, 239 former preterm infants with gestational age (GA) ≤ 32 weeks and 264 former full-term born infants with GA ≥ 37 weeks underwent detailed ophthalmologic examination in the age of 4–10 years and perinatal data assessment for risk factor analysis. Ophthalmologic examinations included cover testing, best corrected visual acuity, cycloplegic objective refraction, slit lamp as well as fundus examinations. For association analysis with strabismus, the following data was collected and included in multivariable analysis: sex, age at examination, anisometropia, myopic and hyperopic refractive error (≥ 3 dioptres), astigmatism, birth weight percentile, gestational age, retinopathy of prematurity occurrence, maternal age at childbirth, mother smoking, breastfeeding < 3 months, artificial ventilation, intraventricular bleeding, and other perinatal adverse events.ResultsOverall, 4/264 (2%) full-term infants, 15/125 (12%) preterm-infants with GA 29–32 weeks without ROP, 13/59 (22%) preterm infants with GA ≤ 28 weeks without ROP and 14/55 (26%) with GA ≤ 32 weeks with retinopathy of prematurity were affected by strabismus. In the multivariable regression model strabismus was associated with GA (OR = 0.84 per week; p = 0.001), hyperopic refractive error (OR = 4.22; p = 0.002) and astigmatism (OR = 1.68; p = 0.02).ConclusionThis investigation highlights that low gestational age and refraction of the eye are independent risk factors for strabismus, while the other factors show less independent influence.

Intraocular lens power calculations in short eyes using 7 formulas

To investigate the accuracy of 7 intraocular lens (IOL) calculation formulas in predicting refractive outcome in eyes with axial lengths (AL) equal to or less than 22.0mm and to evaluate factors contributing to prediction errors. Cullen Eye Institute, Baylor College of Medicine, Houston, Texas, and private practice, Mesa, Arizona, USA. Retrospective case series. Eighty-six eyes of 67 patients were included. Seven IOL calculation formulas were evaluated: Barrett Universal II, Haigis, Hill-RBF, Hoffer Q, Holladay 1, Holladay 2, and Olsen. The refractive prediction error was calculated as the difference between the postoperative refraction and the refraction predicted by each formula. The mean refractive prediction error and median absolute error were also calculated. The Hoffer Q and Holladay 2 formulas produced myopic refractive prediction errors of -0.22 diopter (D) and -0.23 D, respectively, and the Olsen formula produced a hyperopic refractive prediction error of +0.27 D (all P<.05). Without adjustment of the mean refractive prediction errors to zero, the only difference between formulas was that Hill-RBF had a statistically significantly smaller median absolute error than Hoffer Q (P<.05). With adjustment of the mean refractive prediction errors to zero, there were no statistically significant differences in the median absolute errors between the 7 formulas (P=.076). The Hoffer Q and Holladay 2 formulas produced slightly myopic refractive prediction errors, and the Olsen formula produced hyperopic refractive prediction errors. When the mean numerical refractive prediction error was adjusted to zero, no statistically significant differences in the median absolute error were found between the 7 formulas.

The correlation of hyperopia and choroidal thickness, vessel diameter and area.

This study evaluates the effect of axial length and hyperopia error on macular choroidal thickness as well as choroidal vessel lumen diameter and area with EDI-OCT in short eyes. The study includes 64 volunteers who are over 18years of ages and applied to Eye Clinic of Ankara Training and Research Hospital. Choroidal thickness, choroidal vessel lumen diameter and areas were measured with Spectralis® OCT device using EDI technique. The study group included 44 volunteers with hyperopic refractive error, and control group included 20 emmetropic volunteers. Macular choroid was statistically significantly thicker in all quadrants as the hyperopia error increased (p<0.001). There was a statistically significant negative correlation between axial lengths and macular choroidal thicknesses in all quadrants (p<0.001). There was a statistically significant difference in choroidal vessel lumen diameter and area between hyperopia groups for both large and small vessels (p<0.01). The relationships between mean axial length and mean large choroidal vessel diameter and mean area measurements were negatively correlated and they were statistically significant. On the other hand, there was no such negative correlation with small choroidal vessels that have small diameter and area. Macular choroid thickens as the hyperopic error increases as well as axial length decreases in short eyes. The diameters and areas of noticeable large choroidal vessels in EDI-OCT also increase. These findings in EDI-OCT measurements may play a role in developing population nomograms, as a correcting parameter and in understanding the pathophysiology of certain diseases in short eyes.

Prevalence and association of refractive anisometropia with near work habits among young schoolchildren: The evidence from a population-based study.

BackgroundLifestyle behaviour may play a role in refractive error among children, but the association between near work habits and refractive anisometropia remains unclear.MethodsWe estimated the prevalence of refractive anisometropia and examined its association with near work activities among 23,114 children in the Myopia Investigation Study in Taipei who were grade 2 elementary school students at baseline in 2013 and 2014. Baseline data on demographics, medical history, parental history and near work habits were collected by parent-administered questionnaire survey. Refractive status was determined by cycloplegic autorefraction. Refractive anisometropia was defined as the spherical equivalent difference ≥ 1.0 diopter between eyes.ResultsThe prevalence of refractive anisometropia was 5.3% (95% confidence interval [CI], 5.0% to 5.6%). The prevalence and severity of refractive anisometropia increased with both myopic and hyperopic refractive error. Multivariate logistic regression analysis revealed that refractive anisometropia was significantly associated with myopia (odds ratio [OR], 2.98; 95% CI, 2.53–3.51), hyperopia (OR, 2.37; 95% CI, 1.98–2.83), degree of astigmatism (OR, 1.005; 95% CI, 1.005–1.006), amblyopia (OR, 2.54; 95% CI, 2.06–3.12), male gender (OR, 0.88; 95% CI, 0.78–0.99) and senior high school level of maternal education (OR, 0.69; 95% CI, 0.52–0.92). Though anisometropic children were more likely to spend more time on near work (crude OR, 1.15; 95% CI, 1.02–1.29) and to have less eye-to-object distance in doing near work (crude OR, 1.15; 95% CI, 1.01–1.30), these associations became insignificant after additional adjustment for ocular, demographic and parental factors.ConclusionsThe present study provides large-scale, population-based evidence showing no independent association between refractive anisometropia and near work habits, though myopia is associated with refractive anisometropia.

Smoking and Eye Pathologies. A Systemic Review. Part I. Anterior Eye Segment Pathologies.

Tobacco smoking has detrimental influence on human health and is one of the leading causes of preventable mortality worldwide, associated with lung cancer, chronic obstructive lung disease and cardiovascular disease. The analysis of the influence of tobacco smoking on pathology of the anterior segment of the eye in adults and children. A comprehensive review of the literature performed through MEDLINE and PubMed searches, was published during the period 2000-2016. In adults, tobacco smoking is associated with hyperopia, delayed corneal epithelial healing and progression of Fuchs' endothelial corneal dystrophy. Smoking is a strong risk factor for age-related nuclear cataract. However, smoking is not associated with pterygium, and its influence on dry eye symptoms, central corneal thickness and progression of primary open glaucoma remains controversial. Smoking during pregnancy increases risk of convergent or divergent strabismus or poor stereo acuity, however, its influence on anophtalmia, microphtalmia, amblyopia and hyperopic refractive error is controversial. Tobacco smoking plays an important role in the pathogenesis of many diseases of anterior eye segment leading to visual impairment in adults and children.

Retinal nerve fiber layer thickness in normal Egyptian population

Purpose The aim of this study was to collect normative retinal nerve fiber layer thickness (RNFLT) data in the Egyptian population using the Spectralis SD-OCT and to assess its correlations with demographic data and ocular parameters. Participants and methods A total of 100 healthy eyes of 100 Egyptian individuals were enrolled in this study. BMI was calculated for each participant. Uncorrected visual acuity (UCVA) and best-corrected visual acuity were measured and converted to the logarithm of the minimum angle of resolution (logMAR). Autorefraction, keratometric (K) readings, and axial length were obtained. Patients underwent a comprehensive ophthalmic examination, including cup disc (CD) ratio and intraocular pressure (IOP) measurement. RNFLT measurement by Spectralis SD-OCT scanning was carried out using circular scans of the retinal nerve fiber layer of a diameter of 3.4 mm centered on the optic nerve head. Results The mean global (G) RNFLT was 101.74±10.05 μm (range: 79.0–123.0 μm). The mean RNFLT was the least at the temporal (T) sector, followed by nasal (N), nasal superior (NS), nasal inferior (NI), temporal superior (TS), and temporal inferior (TI) sectors. Using Pearson’s correlation, age showed a significant negative correlation with T and TI sectors. BMI showed a significant positive correlation with the G RNFLT and NS and TI sectors. Square root of logMAR of UCVA showed a significant negative correlation with the G RNFLT and NI and TI sectors. Spherical equivalent showed a significant positive correlation with the G RNFLT and the N sector. K-readings showed a significant positive correlation with the G RNFLT and N, NS, TS, NI, and TI sectors. IOP showed a significant negative correlation with the NS sector only. CD ratio showed a significant negative correlation with the G RNFLT and NS, TS, and TI sectors. Axial length showed a significant negative correlation with the G RNFLT and N, NS, and TI sectors. Using regression analysis, RNFLT was directly related to better UCVA, hyperopic refractive error, and steeper cornea, and inversely related to age, IOP, and CD ratio. Conclusion The mean RNFLT was the least at the T sector, followed by N, NS, NI, TS, and TI sectors, respectively. RNFLT was directly related to better UCVA, hyperopic refractive error, and steeper cornea, and inversely related to age, IOP, and CD ratio.

Refractive errors in children and adolescents in Bucaramanga (Colombia).

The aim of this study was to establish the frequency of refractive errors in children and adolescents aged between 8 and 17 years old, living in the metropolitan area of Bucaramanga (Colombia). This study was a secondary analysis of two descriptive cross-sectional studies that applied sociodemographic surveys and assessed visual acuity and refraction. Ametropias were classified as myopic errors, hyperopic errors, and mixed astigmatism. Eyes were considered emmetropic if none of these classifications were made. The data were collated using free software and analyzed with STATA/IC 11.2. One thousand two hundred twenty-eight individuals were included in this study. Girls showed a higher rate of ametropia than boys. Hyperopic refractive errors were present in 23.1% of the subjects, and myopic errors in 11.2%. Only 0.2% of the eyes had high myopia (≤-6.00 D). Mixed astigmatism and anisometropia were uncommon, and myopia frequency increased with age. There were statistically significant steeper keratometric readings in myopic compared to hyperopic eyes. The frequency of refractive errors that we found of 36.7% is moderate compared to the global data. The rates and parameters statistically differed by sex and age groups. Our findings are useful for establishing refractive error rate benchmarks in low-middle-income countries and as a baseline for following their variation by sociodemographic factors.

Intended Flap Decentration in Hyperopic Laser In Situ Keratomileusis (LASIK) in Eyes with off-Centered Corneal Apex

Laser in situ keratomileusis (LASIK) has been described as a means to correct hyperopia . Excimer laser correction of hyperopic refractive errors involves the para central removal of a negative meniscus of stromal tissue to indirectly produce central steepening of the anterior corneal surface.

Visual outcomes after spectacles treatment in children with bilateral high refractive amblyopia

PurposeThe aim was to investigate the visual outcomes of treatment with spectacles for bilateral high refractive amblyopia in children three to eight years of age.MethodsChildren with previously untreated bilateral refractive amblyopia were enrolled. Bilateral high refractive amblyopia was defined as visual acuity (VA) being worse than 6/9 in both eyes in the presence of 5.00 D or more of hyperopia, 5.00 D or more of myopia and 2.00 D or more of astigmatism. Full myopic and astigmatic refractive errors were corrected, and the hyperopic refractive errors were corrected within 1.00 D of the full correction. All children received visual assessments at four‐weekly intervals. VA, Worth four‐dot test and Randot preschool stereotest were assessed at baseline and every four weeks for two years.ResultsTwenty‐eight children with previously untreated bilateral high refractive amblyopia were enrolled. The mean VA at baseline was 0.39 ± 0.24 logMAR and it significantly improved to 0.21, 0.14, 0.11, 0.05 and 0.0 logMAR at four, eight, 12, 24 weeks and 18 months, respectively (all p = 0.001). The mean stereoacuity (SA) was 1,143 ± 617 arcsec at baseline and it significantly improved to 701, 532, 429, 211 and 98 arcsec at four, eight, 12, 24 weeks and 18 months, respectively (all p = 0.001). The time interval for VA achieving 6/6 was significantly shorter in the eyes of low spherical equivalent (SE) (−2.00 D < SE < +2.00 D) than in those of high SE (SE > +2.00 D) (3.33 ± 2.75 months versus 8.11 ± 4.56 months, p = 0.0005). All subjects had normal fusion on Worth four‐dot test at baseline and all follow‐up visits.ConclusionRefractive correction with good spectacles compliance improves VA and SA in young children with bilateral high refractive amblyopia. Patients with greater amounts of refractive error will achieve resolution of amblyopia with a longer time.

Prevalence and Risk Factors of Strabismus in a UK Multi-ethnic Birth Cohort

ABSTRACTPurpose: To determine the prevalence, types and early-life risk factors associated with strabismus in a multi-ethnic birth cohort of children aged 4-5 years in the first year of school.Methods: Data were collected prospectively over a 3-year period (2012-2015) from children participating in the vision screening program provided by orthoptists and carried out in schools located in the city of Bradford, UK. Prevalence of strabismus was determined for 17,018 children aged 4 to 5 years. Data linkage was undertaken for 4563 children participating in the Born in Bradford birth cohort study and the vision screening program. 4067 children had complete data and were included in the multivariable regression analyses to determine associated factors.Results: 401/17018 (2.4%) children were found to have either a constant or an intermittent strabismus; 179/401 (45%) had an esotropic deviation, 214 (53%) an exotropic deviation, and 8 (2%) had a vertical deviation. No significant difference in the overall prevalence of strabismus was found between the white British, Pakistani, or children of other ethnic origin (P=0.41). Multivariable analysis showed that children of white British ethnicity have twice the odds of having esotropia (OR 2.4, 95% CI: 1.1, 5.3). The odds of having esotropia were highest in children with a hyperopic mean spherical equivalent (OR 2.0, 95% CI: 1.7, 2.6). There was some evidence of an interaction between ethnicity and mean spherical equivalent in children with esotropia (P=0.058).Conclusions: Prevalence of strabismus is consistent with other population-based studies in this cohort of children aged 4-5 years. Prevalence of esotropia (constant or intermittent) is greater in the white British population, odds of esotropia increased with increasing hyperopic refractive error in both white British and Pakistani children. Exotropia (constant or intermittent) was not found to be associated with refractive error, ethnicity, or other early life factors.

Clinical features of cataract extraction with negative power intraocular lens implantation in high myopia patients

PurposeTo evaluate the clinical features of high myopic eyes with cataracts implanted with negative power intraocular lenses (IOLs) at the time of cataract surgery.MethodsA retrospective chart review was conducted of 18 eyes of 14 patients who underwent cataract surgery with negative power IOLs and 10 eyes in 9 patients with low power IOLs. We investigated axial length, IOL power, preoperative and postoperative best‐corrected visual acuity (BCVA) and preoperative and postoperative spherical equivalent (SE) refractive errors.ResultsMean BCVA showed significant improvement in both groups. We measured postoperative SE refraction and the difference between the mean intended and the mean achieved SE refractive errors in the negative power group (17 eyes) was +1.59 ± 1.34 D and +0.31 ± 0.50 D in the low power group.ConclusionsBCVA was significantly improved in the majority of eyes, although they had myopic macular degeneration or posterior staphyloma. However, the mean achieved postoperative SE refraction was more hyperopic than the predicted postoperative SE error. Additionally, hyperopic refractive error was greater in the negative power group than the low power group. Therefore, we recommend that postoperative hyperopic refractive error should be considered when performing cataract surgery in high myopic patients.

Adaptation of horizontal eye alignment in the presence of prism in young children.

Young children experience decreased convergence and increased accommodation demands relative to adults, as a result of their small interpupillary distance and hyperopic refraction. Those with typical amounts of hyperopic refractive error must accommodate more than an emmetrope to achieve focused retinal images, which may also drive additional convergence through the neural coupling. Adults and older children have demonstrated vergence adaptation to a variety of visual stimuli. Can vergence adaptation help younger children achieve alignment in the presence of these potentially conflicting demands? Purkinje image eye tracking and eccentric photorefraction were used to record simultaneous vergence and accommodation responses in adults and young children (3–6 years). To assess vergence adaptation, heterophoria was monitored before, during, and after adaptation induced by both base-in and base-out prisms. Adaptation was observed in both adults and young children with no significant effect of age, F(1, 34) = 0.014, p = 0.907. Changes in accommodation between before, during, and after adaptation were less than 0.5 D in binocular viewing. Typically developing children appear capable of vergence adaptation, which might play an important role in the maintenance of eye alignment under their changing visual demands.

A comparison of plusoptiX A12 measurements with cycloplegic refraction

To test the accuracy and reliability of the plusoptiX A12 in detecting amblyogenic risk factors. We prospectively collected data on children undergoing screening with the plusoptiX A12, cycloplegic refraction, and complete ophthalmic examination. American Association for Pediatric Ophthalmology and Strabismus (AAPOS) 2013 guidelines for the detection of amblyogenic risk factors were used for plusoptiX A12 screening and comparison of the results of both examination modes. Data on 402 eyes of 201 children (mean age, 7.63±3.41 years) was collected. Mean (with standard deviation) cycloplegic refraction results were as follows: sphere, 0.88±1.5 D; cylinder, -0.61±0.74 D; axis, 71.17±71.04; and spherical equivalent, 0.68±2.63. The plusoptiX A12 measurements were as follows: sphere, 0.58±1.4 D; cylinder, -0.66±0.77 D; axis, 77.3±68.9; and spherical equivalent, 0.25±1.3. We found a strong correlation (Pearson) for sphere (r=0.91), cylinder (r=0.81), and axis (r=0.7). The mean difference of the myopic spherical component between the plusoptiX and cycloplegic refraction was -0.048±0.55 (95% LoA, +1.04 to -1.14 D); for the hyperopic spherical component, 0.37±0.93 (LoA, +2.20 to -1.45 D); and for the cylindrical component, 0.05±0.32 (LoA, +0.68 to -0.57D). The sensitivity, specificity, positive and negative predictive values for myopia were, respectively, 86%, 93%, 82%, and 94%; for astigmatism, 85%, 98%, 88% and 98%; and for hyperopia, 40%, 100%, 100%, and 98%. The plusoptiX A12 accuracy is high in all subgroups but better in the myopic, astigmatic, and anisometropic subgroups. Reliability was lower in the hyperopic eyes, possibly resulting in underestimation of hyperopic refractive error.

Fixation Stability and Refractive Error After Cataract Surgery in Highly Myopic Eyes

To analyze the refractive error in highly myopic eyes after cataract surgery and investigate the possible impact of fixation stability on it. Secondary data analysis from a previous prospective study. Clinical data of 98 eyes of 98 consecutive patients with high myopia and 42 eyes of 42 controls, which underwent cataract surgery, were analyzed. Refractive error was calculated 1month after surgery based on both Sanders-Retzlaff-Kraff theoretic (SRK/T) and Holladay 1 formulas. Fixation stability was evaluated using the Macular Integrity Assessment microperimeter system, which assessed the fixation pattern in terms of 63% and 95% of the bivariate contour ellipse area (BCEA). Multiple linear regression analysis was performed to identify independent predictors of postoperative refractive error. The highly myopic cataract group had greater hyperopic refractive errors (P < .001 for both formulas) and larger 63% and 95% BCEA values (P= .033 and P= .034) than the control group. In the highly myopic group, the factors 63% or 95% BCEA were positively correlated with the postoperative refractive error (SRK/T formula, r= 0.383, P < .001 and r= 0.320, P= .002, respectively). Multiple linear regression analysis showed that with the SRK/T formula, postoperative refractive error in highly myopic eyes was significantly correlated with axial length (β= 0.491, P < .001), 63% BCEA (β= 0.181, P= .045), and corneal curvature (β=-0.190, P= .024). The refractive error was no longer associated with corneal curvature after using the Holladay 1 formula. Highly myopic eyes usually had hyperopic refractive errors after cataract surgery. Fixation stability might serve as an important determinant of postoperative refractive errors in this population.

Acute acquired comitant esotropia related to excessive Smartphone use.

BackgroundTo describe the clinical characteristics and outcomes of acute acquired comitant esotropia (AACE) related to excessive smartphone use in adolescents.MethodsThe medical records of 12 patients with AACE and a history of excessive smartphone use were retrospectively reviewed, and the duration of smartphone use, angle of deviation, refractive error, stereopsis, and treatment options were analyzed.ResultsAll patients showed convergent and comitant esotropia ranging from 15 to 45 prism diopters (PD; average: 27.75 ± 11.47 PD) at far fixation. The angle of deviation was nearly equivalent for far and near fixation. Every patient used a smartphone for more than 4 h a day over a period of several months (minimum 4 months). Myopic refractive errors were detected in eight patients (average:−3.84 ± 1.68 diopters (D]), and the remaining four patients showed mild hyperopic refractive error (average: +0.84 ± 0.53 D). Reductions in esodeviation were noted in all patients after refraining from smartphone use, and bilateral medial rectus recession was performed in three patients with considerable remnant esodeviation. Postoperative exams showed orthophoria with good stereoacuity in these patients.ConclusionExcessive smartphone use might influence AACE development in adolescents. Refraining from smartphone use can decrease the degree of esodeviation in these patients, and remnant deviation can be successfully managed with surgical correction.

Clinical Features of Cataract Extraction with Negative-Power Intraocular Lens Implantation in High Myopia

Purpose: To evaluate the clinical features of high myopic eyes with cataracts implanted with negative power intraocular lenses (IOLs) at the time of cataract surgery. Methods: A retrospective chart review was conducted of 18 eyes of 14 patients who underwent cataract surgery with negative power IOLs and 10 eyes in 9 patients with low power IOLs. We investigated axial length, IOL power, preoperative and postoperative best-corrected visual acuity (BCVA) and preoperative and postoperative spherical equivalent (SE) refractive errors. Results: Mean BCVA showed significant improvement in both groups. We measured postoperative SE refraction and the difference between the mean intended and the mean achieved SE refractive errors in the negative power group (17 eyes) was +1.59 ± 1.34 D and +0.31 ± 0.50 D in the low power group. Conclusions: BCVA was significantly improved in the majority of eyes, although they had myopic macular degeneration or posterior staphyloma. However, the mean achieved postoperative SE refraction was more hyperopic than the predicted postoperative SE error. Additionally, hyperopic refractive error was greater in the negative power group than the low power group. Therefore, we recommend that postoperative hyperopic refractive error should be considered when performing cataract surgery in high myopic patients. J Korean Ophthalmol Soc 2016;57(6):898-904

Five-Year Progression of Refractive Errors and Incidence of Myopia in School-Aged Children in Western China.

BackgroundTo determine the change in refractive error and the incidence of myopia among school-aged children in the Yongchuan District of Chongqing City, Western China.MethodsA population-based cross-sectional survey was initially conducted in 2006 among 3070 children aged 6 to 15 years. A longitudinal follow-up study was then conducted 5 years later between November 2011 and March 2012. Refractive error was measured under cycloplegia with autorefraction. Age, sex, and baseline refractive error were evaluated as risk factors for progression of refractive error and incidence of myopia.ResultsLongitudinal data were available for 1858 children (60.5%). The cumulative mean change in refractive error was −2.21 (standard deviation [SD], 1.87) diopters (D) for the entire study population, with an annual progression of refraction in a myopic direction of −0.43 D. Myopic progression of refractive error was associated with younger age, female sex, and higher myopic or hyperopic refractive error at baseline. The cumulative incidence of myopia, defined as a spherical equivalent refractive error of −0.50 D or more, among initial emmetropes and hyperopes was 54.9% (95% confidence interval [CI], 45.2%–63.5%), with an annual incidence of 10.6% (95% CI, 8.7%–13.1%). Myopia was found more likely to happen in female and older children.ConclusionsIn Western China, both myopic progression and incidence of myopia were higher than those of children from most other locations in China and from the European Caucasian population. Compared with a previous study in China, there was a relative increase in annual myopia progression and annual myopia incidence, a finding which is consistent with the increasing trend on prevalence of myopia in China.

Association Between Ocular Dominance and Anisometropic Hyperopia

Introduction and PurposeAnisometropia, a relative difference in the refractive state of the two eyes, is common in hyperopic patients. We investigated the association between ocular dominance (sighting dominance) and refractive asymmetry in patients with hyperopia.MethodsThis retrospective study included 223 hyperopic patients with a mean age of 10.1 ± 3.6 years (range 3 to 21 years). Refractive error was measured with cycloplegic refraction, and axial length was measured with IOLMaster® (Carl Zeiss Meditec, Dublin, CA). Ocular dominance was assessed with the hole-in-the-card test. The amount of hyperopic anisometropia was subdivided into four groups: less than 0.50 D, 0.50–0.99 D, 1.00–1.99 D, and 2.00 D or greater.ResultsOcular dominance of the right and left eye was seen in 66% and 34% of the patients, respectively. The nondominant eye had higher hyperopia, astigmatism, and shorter axial length than the dominant eye (P < 0.001). In the group with spherical equivalent anisometropia of ≥0.50 D in particular, the nondominant eye was significantly more hyperopic and had shorter axial length than the dominant eye (both P < 0.001).ConclusionsThe current study revealed that the nondominant eye had a greater hyperopic refractive error and shorter axial length than the dominant eye, in patients who had a high degree of anisometropia in particular.

Phenotypic characterization of X-linked retinoschisis: Clinical, electroretinography, and optical coherence tomography variables.

Aims:To study the phenotypic characteristics of X-linked retinoschisis (XLRS) and report the clinical, electroretinogram (ERG), and optical coherence tomography (OCT) variables in Indian eyes.Design:A retrospective study.Materials and Methods:Medical records of 21 patients with retinoschisis who were genetically confirmed to have RS1 mutation were reviewed. The phenotype characterization included the age of onset, best-corrected visual acuity, refractive error, fundus findings, OCT, and ERG.Statistical Analysis Used:Data from both the eyes were used for analysis. A P < 0.05 was set as statistical significance. Data were not normally distributed (P < 0.05, Shapiro wilk); hence, nonparametric tests were used for statistical analysis.Results:All were males whose mean age of presentation was 9 years. Visual acuity was moderately impaired (median 0.6 logMAR, interquartile range: 0.47, 1) in these eyes with a hyperopic refractive error of median +1.75 Ds (interquartile range: +0.50 Ds, +4.25 Ds). About 54.7% of the eyes had both foveal and peripheral schisis, isolated foveal schisis was seen in 28.5% of the eyes, and schisis with retinal detachment was seen in 16.6% of the eyes. The inner nuclear layer was found to be commonly involved in the schisis, followed by outer nuclear and plexiform layers as evident on OCT. On ERG, a- and b-wave amplitudes were significantly reduced in eyes with foveal and peripheral schisis when compared to the eyes with only foveal schisis (P < 0.05).Conclusions:XLRS has phenotypic heterogeneity as evident on OCT, ERG, and clinical findings.