Low-dose atropine 0.01% for the treatment of childhood myopia: a pan-India multicentric retrospective study.

OBJECTIVE: The objective of this study was to assess the efficacy of low-dose atropine 0.01% in controlling myopia progression among Indian children over a 2-year period. METHODS: This retrospective study, conducted across 20 centres in India, monitored the progression of myopia over 2 years after initiating treatment with 0.01% atropine eye drops. This included children between 6 and 14 years with baseline myopia ranging from -0.5 D to -6 D, astigmatism≤-1.5 D, anisometropia ≤ -1 D and documented myopia progression of ≥0.5 D in the year prior to starting atropine. Subjects with any other ocular pathologies were excluded. RESULTS: A total of 732 children were included in the data analysis. The mean age of the subjects was 9.3±2.7 years. The mean myopia progression at baseline (1 year before starting atropine) was -0.75±0.31 D. The rate of myopia progression was higher in younger subjects and those with higher baseline myopic error. After initiating atropine, myopia progression significantly decreased to -0.27±0.14 D at the end of the first year and -0.24±0.15 D at the end of the second year (p<0.001). Younger children (p<0.001) and higher baseline myopia (p<0.001) was associated with greater myopia progression and poor treatment response (p<0.001 for both). CONCLUSION: Low-dose atropine (0.01%) effectively reduces myopia progression over 2 years in Indian children.

Myopia and Its Association with Near Work, Outdoor Time, and Housing Type among Schoolchildren in South India.

SIGNIFICANCE: In this comprehensive assessment of environmental associations with refractive status among schoolchildren in India, outdoor time was the key modifiable risk factor associated with myopia rather than time spent on near work. PURPOSE: This study aimed to investigate the environmental risk factors associated with myopia among adolescent schoolchildren in South India. METHODS: Children in grades 8 to 10 from 11 schools in Tamil Nadu, South India, underwent eye examination and risk factor assessments through a modified version of the Sydney myopia questionnaire. Time spent on near work and outdoors was analyzed after division into three groups based on tertiles. Mixed-effects logistic regression was performed to assess the factors associated with myopia. RESULTS: A total of 3429 children (response rate, 78.4%) provided both questionnaire and refraction data. The mean (standard deviation) age was 14 (0.93) years with an equal distribution of sexes. Myopia was present among 867 children (noncycloplegic spherical equivalent refraction, ≤-0.75 D). Refraction was not associated with near work tertiles ( P = .22), whereas less time outdoors was associated with higher myopic refractions ( P = .01). Refraction shifted toward increased myopia with an increase in the near-work/outdoor time ratio ( P = .005). Children living in apartment housing had a higher prevalence of myopia compared with other types of housing ( P < .001). In multivariate analysis, increased time outdoors was a protective factor against myopia (odds ratio, 0.79; 95% confidence interval, 0.63 to 0.99; P = .04), whereas living in apartment housing (odds ratio, 1.27; 95% confidence interval, 1.04 to 1.55; P = .02) was a significant risk factor. CONCLUSIONS: In this cohort of Indian children, outdoor time, increased near-work/outdoor time ratio, and type of housing were the factors associated with myopia. Policies should target implementing a balance between near-work and outdoor time among children.

Prevalence of myopia among urban and suburban school children in Tamil Nadu, South India: findings from the Sankara Nethralaya Tamil Nadu Essilor Myopia (STEM) Study.

PURPOSE: To report the baseline prevalence of myopia among school children in Tamil Nadu, South India from a prospective cohort study. METHODS: Children between the ages of 5 and 16 years from 11 schools in two districts of Tamil Nadu underwent vision screening. All children underwent visual acuity assessment using a Pocket Vision Screener followed by non-cycloplegic open-field autorefraction (Grand Seiko WAM-5500). Myopia was defined as a spherical equivalent (SE) refraction of ≤-0.75 D and high myopia was defined as SE ≤ -6.00 D. Distribution of refraction, biometry and factors associated with prevalence of myopia were the outcome measures. RESULTS: A total of 14,699 children completed vision screening, with 2% (357) of them having ocular abnormalities other than refractive errors or poor vision despite spectacle correction. The remaining 14,342 children (7557 boys; 52.69%) had a mean age of 10.2 (Standard Deviation [SD] 2.8) years. A total of 2502 had myopia in at least one eye, a prevalence of 17.5% (95% CI: 14.7-20.5%), and 74 (0.5%; 95% CI: 0.3-0.9%) had high myopia. Myopia prevalence increased with age (p < 0.001), but sex was not associated with myopia prevalence (p = 0.24). Mean axial length (AL; 23.08 (SD = 0.91) mm) and mean anterior chamber depth (ACD; 3.45 (SD = 0.27) mm) positively correlated with age (p < 0.001). The mean flat (K1; 43.37 (SD = 1.49) D) and steep (K2; 44.50 (SD = 1.58) D) corneal curvatures showed negative correlation with age (p = 0.02 and p < 0.001, respectively). In the multivariable logistic regression, older age and urban school location had higher odds for prevalence of myopia. CONCLUSION: The baseline prevalence of myopia among 5- to 16-year-old children in South India is larger than that found in previous studies, indicating that myopia is becoming a major public health problem in this country.

Fluid reservoir thickness and aberration relationship in keratoconic eyes with scleral lenses.

PURPOSE: To investigate the effect of varying the fluid reservoir (FR) thickness of scleral lenses (SL) on corrected distance visual acuity (CDVA), contrast sensitivity (CS) and higher-order aberrations (HOAs) in keratoconic eyes. METHODS: Forty eyes with keratoconus were fitted with a diagnostic Boston Sight SL having three different FR thicknesses. CDVA, CS and HOAs were measured before and after 30 min of lens wear. An i-Trace aberrometer and anterior segment optical coherence tomography (AS-OCT) were used to measure HOAs and FR thickness, respectively. RESULTS: Statistically significant improvements in CDVA and CS were seen with different FR thickness lenses (p < 0.01). Baseline CDVA (0.22 ± 0.15) improved to 0.03 ± 0.06, 0.04 ± 0.07 and 0.07 ± 0.08 with low, standard and high FR lenses, respectively. Post-hoc testing showed better CDVA with low (p = 0.006) and standard FR (p = 0.009) lenses compared to high FR lenses. Before lens wear, CS was 1.27 ± 0.27, which improved to 1.67 ± 0.11, 1.73 ± 0.12 and 1.66 ± 0.89 with low, standard and high FR lenses, respectively. Lenses with standard FR showed better CS compared with those having low (p = 0.009) and high FRs (p < 0.001). A statistically significant reduction of higher order-root mean square aberrations (HO-RMS), coma, spherical aberration, secondary astigmatism and trefoil were found with all FR thickness lenses compared to baseline (p < 0.01). No significant difference was noted between lenses (p = 0.01). All three lenses corrected almost equal amount of HOAs. A moderate positive correlation was observed between CDVA and HO-RMS (r = 0.61, p < 0.001) for low FR lenses. CONCLUSIONS: BostonSight SCLERALs were found to be very effective in improving vision, CS and reducing HOAs in keratoconus. Lenses with varying FR thickness showed equal effectiveness in visual performance and reducing HOAs. FR thickness should be considered an important factor to provide better vision and CS by minimising HOAs, as well as to maintain the normal physiology of eyes with keratoconus.

RETRACTED: Young adults with myopia have lower concentrations of neuromodulators-dopamine and melatonin in serum and tear.

This article has been retracted: please see Elsevier Policy on Article Withdrawal (https://www.elsevier.com/about/our-business/policies/article-withdrawal). This article has been retracted at the request of the authors, as questions have arisen in the interim regarding the validity of some of the methods and therefore the results. The authors have provided the following statement: "We have addressed a question raised by the reader on the higher levels of dopamine and melatonin in serum and tear levels reported in this study in Myopia along with controls. Serum and tear levels of dopamine and melatonin in Myopia cases were estimated by HPLC (UV detector) is reported by us in a higher order of magnitude (ng/mL) in both specimens compared to most of the reported data (pg/mL) that are reported based on LC/MS/MS or kit based immunoassay(pg/mL). The sample extraction protocol that we followed before estimation of the analytes was based on removing protein by precipitation methods with no further purification by liquid/liquid extraction/use of SPE cartridges as reported in other published reports. This could have possibly extracted related compounds, such as the closely related indoles in the case of melatonin extraction; the other Dopamine related metabolites respectively. The possibility of confounding by other metabolites in our estimation has not been ruled out by any targeted analysis. This we agree is a limitation in the specificity of the protocol we have followed that may have contributed to the nmol range of detection. We have done the HPLC method of analysis and detection (UV) and not LC-MS/MS or immunoassays by kit method whose sensitivity and specificity are reportedly higher based on the range of testing reported in serum. The lower detection limit of our protocol was not in pg/mL but in ng/mL. Parity in the levels reported was discussed in the manuscript attributing to the analytical method adopted and interpretation based on relative changes. Amongst ocular fluids, Aqueous humor by similar HPLC analysis reportedly shows up to 200 ng/ml in literature (Alkozi, H. et al 2017). However, based on our serum data, we feel that further validation studies and method comparisons are required. The method of estimation of the neurotransmitters HPLC (UV detection) seems to have influenced the absolute levels of dopamine and melatonin in the cases and controls studied and therefore casts doubts on the validity of these data. Though further interpretations can be made on relative changes, we decide to withdraw our paper, to work further on the method comparison. We sincerely apologize for the inconvenience to the readers."

Nearwork-induced transient myopia and accommodation function before and after laser-assisted in situ keratomileusis surgery.

Purpose: To assess the change in Near Induced Transient Myopia (NITM) and other accommodation parameters, before and after undergoing LASIK surgery for myopia correction. Methods: Twenty-nine myopic subjects were recruited from a tertiary eye hospital in India. Age range was 21 to 35 years with an average age of 26.1 ± 3.5 years. Mean spherical equivalent was -3.86 D ± 1.50 D presurgery. NITM, lag of accommodation, near point of convergence (NPC), accommodative amplitude (AA), and binocular near accommodative facility (AF) were measured. All data were collected 21 days prior to and 30 days after LASIK surgery. Results: NITM, lag of accommodation and amplitude of accommodation were significantly lower (NITM -0.05 ± 0.15, Lag 0.38 ± 0.38, AA 10.27 ± 2.24) after surgery when compared to before (NITM 0.26 ± 0.12, Lag 0.77 ± 0.51, AA 12.18 ± 2.02; P < 0.001). Accommodative facility increased and near point of convergence was significantly more distal following surgery (AF 10.70 ± 2.29, NPC 7.96 ± 1.63) when compared to prior (AF 8.65 ± 2.74, NPC 5.62 ± 1.71; P < 0.001). Conclusion: Significant changes in NITM and accommodation function should be expected in the short term following LASIK surgery. This study supports the importance of evaluating accommodative parameters and patient counselling prior to and following refractive surgery.

The Sankara Nethralaya Tamil Nadu Essilor Myopia (STEM) Study-Defining a Threshold for Non-Cycloplegic Myopia Prevalence in Children.

The aim of this study was to investigate the agreement between cycloplegic and non-cycloplegic autorefraction with an open-field auto refractor in a school vision screening set up, and to define a threshold for myopia that agrees with the standard cycloplegic refraction threshold. The study was conducted as part of the Sankara Nethralaya Tamil Nadu Essilor Myopia (STEM) study, which investigated the prevalence, incidence, and risk factors for myopia among children in South India. Children from two schools aged 5 to 15 years, with no ocular abnormalities and whose parents gave informed consent for cycloplegic refraction were included in the study. All the children underwent visual acuity assessment (Pocket Vision Screener, Elite school of Optometry, India), followed by non-cycloplegic and cycloplegic (1% tropicamide) open-field autorefraction (Grand Seiko, WAM-5500). A total of 387 children were included in the study, of whom 201 were boys. The mean (SD) age of the children was 12.2 (±2.1) years. Overall, the mean difference between cycloplegic and non-cycloplegic spherical equivalent (SE) open-field autorefraction measures was 0.34 D (limits of agreement (LOA), 1.06 D to -0.38 D). For myopes, the mean difference between cycloplegic and non-cycloplegic SE was 0.13 D (LOA, 0.63D to -0.36D). The prevalence of myopia was 12% (95% CI, 8% to 15%) using the threshold of cycloplegic SE ≤ -0.50 D, and was 14% (95% CI, 11% to 17%) with SE ≤ -0.50 D using non-cycloplegic refraction. When myopia was defined as SE of ≤-0.75 D under non-cycloplegic conditions, there was no difference between cycloplegic and non-cycloplegic open-field autorefraction prevalence estimates (12%; 95% CI, 8% to 15%; p = 1.00). Overall, non-cycloplegic refraction underestimates hyperopia and overestimates myopia; but for subjects with myopia, this difference is minimal and not clinically significant. A threshold of SE ≤ -0.75 D agrees well for the estimation of myopia prevalence among children when using non-cycloplegic refraction and is comparable with the standard definition of cycloplegic myopic refraction of SE ≤ -0.50 D.

Comparison of axial length using a new swept-source optical coherence tomography-based biometer - ARGOS with partial coherence interferometry- based biometer -IOLMaster among school children.

PURPOSE: To compare the axial length measurements obtained by a new swept source optical coherence tomography based biometer-ARGOS with partial coherence interferometry based biometer -IOL master in school children between the ages of 11-17. METHODS: A prospective, cross-sectional, device comparison study was conducted in a school vision screening program comparing the axial length (AL) and corneal curvature (K) measurements obtained by two biometers- ARGOS and IOL master. Children with 6/9 vision or better, without any ocular abnormalities were included in the study. Two trained optometrists performed the measurements and were masked for the outcome measures. RESULTS: The sample size was 188 with a mean(SD) age of 13.88±1.69 years, of which 101 were boys. The mean (SD) AL was 23.94± 1.01 mm with Argos and 23.83 ± 1.03 mm with IOL Master (paired t-test, p>0.05). The mean K was 43.62D±1.59 with Argos and 43.64D±1.61 with IOL master (paired t-test, p>0.05). There was a strong positive correlation between the biometers for AL (r = 1.00, p<0.0001) and K (r = 0.99, p<0.0001). The mean difference in axial length between the two biometers was 0.11± 0.04 mm and the limits of agreement were between -0.02 to -0.19. The mean difference in corneal curvature was 0.02±0.15D and the limits of agreement were between -0.28 to 0.32D. CONCLUSION: Axial length measurements using SS-OCT and PCI based biometers were in agreement and comparable among children between the ages of 11 to 17.

Variant myopia: A new presentation?

Purpose: Variant myopia (VM) presents as a discrepancy of >1 diopter (D) between subjective and objective refraction, without the presence of any accommodative dysfunction. The purpose of this study is to create a clinical profile of VM. Methods: Fourteen eyes of 12 VM patients who had a discrepancy of >1D between retinoscopy and subjective acceptance under both cycloplegic and noncycloplegic conditions were included in the study. Fourteen eyes of 14 age- and refractive error-matched participants served as controls. Potential participants underwent a comprehensive orthoptic examination followed by retinoscopy (Ret), closed-field autorefractor (CA), subjective acceptance (SA), choroidal and retinal thickness, ocular biometry, and higher order spherical aberrations measurements. Results: In the VM eyes, a statistically and clinically significant difference was noted between the Ret and CA and Ret and SA under both cycloplegic and noncycloplegic conditions (multivariate repeated measures analysis of variance, P < 0.0001). A statistically significant difference was observed between the VM eyes, non-VM eyes, and controls for choroidal thickness in all the quadrants (Univariate ANOVA P < 0.05). The VM eyes had thinner choroids (197.21 ± 13.04 µ) compared to the non-VM eyes (249.25 ± 53.70 µ) and refractive error-matched controls (264.62 ± 12.53 µ). No statistically significant differences between groups in root mean square of total higher order aberrations and spherical aberration were observed. Conclusion: Accommodative etiology does not play a role in the refractive discrepancy seen in individuals with the variant myopic presentation. These individuals have thinner choroids in the eye with variant myopic presentation compared to the fellow eyes and controls. Hypotheses and clinical implications of variant myopia are discussed.

Near work-induced transient myopia in Indian subjects.

PURPOSE: The aim was to determine the characteristics of near work-induced transient myopia (NITM) in asymptomatic Indian subjects and the influence of target size and contrast. METHODS: Two studies were conducted: First, 24 myopes and 24 emmetropes viewed four targets (N8 and N12 with 50 and 90 per cent contrasts) placed at 0.2 m for five minutes. The refractive status was assessed objectively, before and after carrying out the near task, with the Grand Seiko WAM-5500 open-field autorefractor under monocular viewing conditions. Second, a different group of 24 myopes and 24 emmetropes viewed a N12 target with 90 per cent contrast for 60 minutes with pre- and post-refractive state measurements repeated as above. NITM was defined as the difference between pre-task and post-task distance refraction. RESULTS: In the first study, myopes demonstrated an initial post-task myopic shift of 0.21 D, whereas emmetropes demonstrated a small hyperopic shift of 0.07 D (p < 0.001). The myopes demonstrated a decay time constant of 6.07 seconds. There was no effect of target size or contrast on the magnitude of the NITM or the decay time constant (p > 0.05). In the second study, myopes showed a NITM of 0.31 D, which was significantly greater than emmetropes (p < 0.001). The myopes demonstrated a decay time constant of 8.16 seconds. CONCLUSION: The magnitude of the NITM was higher in myopes compared to emmetropes for both five minute and 60 minute viewing time. The NITM decayed slightly faster than that found in previous literature for some other ethnic groups. Potential reasons for these findings are discussed.