Peripheral myopic defocus signal affects the efficiency of visual information processing in myopic children.

PURPOSE: Spectacle lenses with peripheral lenslets have shown promise for myopia control by providing peripheral myopic defocus signals. Here, we aimed to investigate the impact of prolonged exposure (>6 months) to peripheral myopic defocus on visual information processing in myopic children. METHODS: The study included 30 myopic children who habitually wore spectacle lenses with highly aspherical lenslets (HAL group) and 34 children who habitually wore single-vision (SV group) spectacles. The quick contrast sensitivity function (qCSF) was used to measure contrast sensitivity (CS) under conditions of no or high noise. Both groups were tested with HAL and SV lenses. The perceptual template model was utilised to fit the contrast sensitivity function (CSF) and determine differences in information processing efficiency through internal additive noise ( N add ) and perceptual template gain (ß). RESULTS: The areas under the log CSF in the SV group were significantly higher than for the HAL group in both zero-noise conditions with the SV test lens (p = 0.03) and high-noise conditions with the HAL test lens (p = 0.02). For 2 cycle per degree (cpd) stimuli, ß was significantly higher in the SV group with the HAL test lens than in the HAL group (p = 0.02), while there was a trend towards a significant difference in ß for 6 cpd stimuli (p = 0.07). However, there were no significant differences in N add between the two groups, with or without noise interference. CONCLUSION: The reduced CS observed in myopic children wearing HAL lenses for 6 months or more may be due to decreased ß. This suggests that prolonged use of spectacle lenses with peripheral myopic defocus signals may compromise the central visual system's ability to process additional external noise, resulting in decreased efficiency in visual information processing.

Effect of myopia-control lenses on central and peripheral visual performance in myopic children.

PURPOSE: To evaluate the short-term effects of three myopia-control lenses, which impose peripheral myopic defocus while providing clear central vision, on central and peripheral visual performance in myopic children. METHODS: Twenty-one myopic children were enrolled in the study. Central visual performance was assessed using the quick contrast sensitivity function. Peripheral visual performance was evaluated by measuring peripheral contrast threshold and global motion perception, while subjects maintained fixation through the central portion of the lens. Single-vision spectacle lenses (SVL), spectacle lenses with highly aspherical lenslets (HAL) and defocus-incorporated soft contact (DISC) lenses were evaluated in random order, followed by orthokeratology (OK) lenses. All tests were performed monocularly on the right eye. RESULTS: The area under the log contrast sensitivity function (AULCSF) with DISC lenses was lower than that with SVL (1.14 vs. 1.40, p < 0.001) and HAL (1.14 vs. 1.33, p = 0.001). HAL increased the temporal visual field contrast threshold compared with OK lenses (p = 0.04), and OK lenses decreased the superior visual field contrast threshold compared with that of SVL (p = 0.04) and HAL (p = 0.005). HAL also increased the peripheral coherence threshold for identifying the contraction movement compared with OK lenses (p = 0.01). CONCLUSIONS: The short-term use of these optical interventions for myopia control exhibited measurable differences in central and peripheral visual performance. Relevant attention could be paid to these differences, especially when children switch to different treatments. DISC lenses exhibited worse central contrast sensitivity than SVL and HAL. Imposing peripheral defocus signals did not affect children's peripheral visual performance compared with SVL. However, considering the poorer peripheral visual performance provided by HAL, OK lenses are recommended for children if there are specific demands for global scene recognition and motion perception.

Eye growth pattern of myopic children wearing spectacle lenses with aspherical lenslets compared with non-myopic children.

INTRODUCTION: To evaluate eye growth of children wearing spectacle lenses with highly aspherical lenslets (HAL), slightly aspherical lenslets (SAL) and single-vision lenses (SVL) compared to eye growth patterns in non-myopes in Wenzhou, China. METHODS: The randomised trial had 170 myopic children (aged 8-13 years) randomly assigned to the HAL, SAL or SVL group. Normal eye growth was examined using 700 non-myopic schoolchildren (aged 7-9 years) in the Wenzhou Medical University-Essilor Progression and Onset of Myopia (WEPrOM) cohort study using logistic function models. Slow, normal and fast eye growth was defined as range of values <25th, 25th-75th and >75th percentiles, respectively. RESULTS: The predicted upper limits of slow eye growth (25th percentile) among non-myopes aged 7-10 years and 11-13 years were 0.20-0.13 and 0.08-0.01 mm (after 2-year period; 0.37-0.33 and 0.29-0.14 mm), respectively, while the upper limits of normal eye growth (75th percentile) were 0.32-0.31 and 0.28-0.10 mm (after 2-year period; 0.58-0.55 and 0.50-0.24 mm), respectively. The 2-year trial had 157 children, 96 of whom wore their lenses full time (everyday ≥12 h/day). The mean 2-year axial length change for HAL, SAL and SVL was 0.34, 0.51 and 0.69 mm (0.28, 0.46 and 0.69 mm in full-time wear), respectively. Slow eye growth was found in 35%, 17% and 2% (44%, 29% and 3% in full-time wear); normal eye growth in 35%, 26% and 12% (44%, 32% and 9% in full-time wear) and fast eye growth in 30%, 57% and 86% (12%, 39% and 88% in full-time wear), respectively (p < 0.001). CONCLUSIONS: The eye growth pattern in approximately 90% wearing HAL full time (compared with about 10% wearing SVL full time) was similar or slower than that of non-myopic children both after 1- and 2-year periods.

Comparison of visual performance between peripheral gradient high-addition multifocal soft contact lenses and orthokeratology.

PURPOSE: The aim of this study was to evaluate the short-term effects of peripheral gradient high-addition multifocal soft contact lenses (MFSCLs) and orthokeratology (Ortho-K lenses) on visual performance in myopic children. METHODS: Thirty myopic children participated in this prospective study. Each participant wore different sets of lenses in the following sequence: single-vision spectacles (SVSPs) as a control, MFSCLs and Ortho-K lenses. Ocular aberrations, topography, high-contrast visual acuity (HCVA), low-contrast visual acuity (LCVA) and accommodation of the right eye were measured with each type of correction on a different day. RESULTS: Compared with SVSPs, high-addition MFSCLs and Ortho-K lenses significantly increased all items of aberrations (all p < 0.05) except trefoil (p = 0.17). MFSCLs induced less coma, root mean square of the third-order aberration (RMS3) and higher order aberrations than Ortho-K lenses (all p < 0.05). No significant difference in HCVA was found across the three correction types (F = 1.19, p = 0.39). In terms of LCVA, MFSCLs performed significantly poorer than SVSPs (difference, 0.16 logMAR; p = 0.001) and slightly worse than Ortho-K lenses (difference, 0.08 logMAR; p = 0.35). No significant difference in decentration was found between the two types of contact lenses, and no associations were observed between decentration and visual acuity at both high- and low-contrast levels (all p > 0.05). For MFSCLs, decentration was positively related to coma (r = 0.43, p = 0.02) and RMS3 (r = 0.44, p = 0.02), which was not the case for Ortho-K lenses. Accommodative facility was worse with MFSCLs than Ortho-K lenses (p = 0.001). CONCLUSION: Multifocal soft contact lenses differed from Ortho-K lenses in aberration profile and LCVA, although decentration was similar. Decentration <1 mm had minimal influence on both HCVA and LCVA for either type of correction, but significantly increased third-order aberrations for MFSCLs, but not Ortho-K lenses.

Comparison of peripheral refraction and higher-order aberrations between orthokeratology and multifocal soft contact lens designed with highly addition.

PURPOSE: To compare peripheral defocus, higher-order aberrations (HOAs), and contrast visual acuity (CVA) in myopic children wearing orthokeratology (OK) lenses and multifocal soft contact lenses (MSCLs) designed with highly addition. METHODS: This is a prospective, nonrandomized, controlled study. Subjects at 8 to 13 years of age with spherical equivalent refraction from - 1.00 to - 5.00 dioptres (D) were included in the OK group (n = 30) and MSCL group (n = 23). Relative peripheral corneal defocus (RPCD) and relative peripheral refraction (RPR) were measured before and after wearing lenses. HOAs including spherical aberration (SA), coma, trefoil, and total HOAs, and high (100%) and low (10%) CVA were compared between the groups. Axial length (AL) was measured before and after wearing the lenses for 1 year. RESULTS: After wearing the lenses, subjects in the MSCL group had RPCD and RPR values similar to the OK group at the paracentral (within 2 mm of the cornea or 20° of the retina, all p > 0.05) but larger than the OK group at the periphery (all p < 0.05). All HOAs increased after wearing the lenses except the trefoil in the MSCL group (all p < 0.05). HOAs increased more in the OK group (all p < 0.05). The 100% and 10% CVAs were worse in the MSCL group (p = 0.02 and p = 0.004). After 1 year, AL elongation was 0.37 mm (SD = 0.16) in the MSCL group and 0.28 mm (0.16) in the OK group (p = 0.06). CONCLUSION: MSCL produced larger myopic defocus at the periphery, increased less HOAs and had worse CVA than OK lens. The high addition of this MSCL did not result in better myopia control efficacy TRIAL REGISTRATION: Chinese Clinical Trial Registry: ChiCTR1800018564. Registered 25 September 2018; retrospectively registered, http://www.chictr.org.cn/showproj.aspx?proj=31376.

Spectacle lenses with slightly aspherical lenslets for myopia control: clinical trial design and baseline data.

OBJECTIVES: Myopia is a major public health problem and it is essential to find safe and effective means to control its progression. The study design and baseline data are presented for a one-year prospective, double-masked, crossover, randomized clinical trial evaluating the efficacy of single vision spectacle lenses with concentric rings of slightly aspherical contiguous lenslets technology (SAL) on myopia control. METHODS: One hundred 8- to 13-year old Chinese children with a refractive error of -0.75 D to -4.75 D were assigned to two groups. In Group 1, SAL and single vision lenses were each worn for 6 months, and Group 2 wore the lenses in the reversed order. Primary outcomes are axial length and spherical equivalent of cycloplegic refractive error. Secondary outcomes included corneal thickness, anterior chamber depth, lens thickness, visual acuity, and lens adaptation. RESULTS: No significant differences in baseline parameters (cycloplegic spherical equivalent, axial length, age) were found between groups (0.49 < p < 0.94). All children adapted well to the test lenses and there was no significant difference in visual acuity between the SAL and single vision lenses (p = 0.27). CONCLUSIONS: The children in the two well balanced groups had comparable visual acuity and adapted well to the test lenses. These results imply that visual acuity can be well improved by SAL lenses. Clear visual acuity provides the assurance for good compliance in this longitudinal study.

The associations of accommodation and aberrations in myopia control with orthokeratology.

PURPOSE: This study aimed to investigate the effect of orthokeratology (OK) on accommodative function and aberrations, to explore the correlations between them and determine what role they play in myopia control. METHODS: In this prospective case-controlled study, 61 children were divided into an OK (n = 30) and a single-vision spectacles (SVS) (n = 31) group. Accommodation and ocular wavefront aberrations in the OK group were measured at baseline and after 1, 3, 6, 9 and 12 months of OK wear, and again at 1 month after stopping OK (13th month). The same procedure was performed in the SVS group at baseline and at 3, 6 and 12 months. Axial length (AL), accommodative lag area and aberrations including spherical aberration (SA), coma and total higher-order aberrations (HOAs) were analysed. RESULTS: During OK wear, the accommodative lag area at each visit was lower than the baseline level (all p < 0.01); all aberrations at each visit were higher than pre-treatment (all p < 0.001). After 1 month of OK treatment, changes in accommodative lag area and SA did not show significant correlation (p = 0.16), but after OK cessation these changes were correlated (p = 0.01). In the OK group, multivariate regression analysis showed changes in accommodative lag area were associated with AL progression in the first 6 months but not in the 1-year analysis. For the SVS group, there were no significant changes in the accommodative lag area or any aberrations during the study period. CONCLUSIONS: Increased HOAs and improved accommodative accuracy were observed during OK treatment, but began to regress after the cessation of OK. A significant positive correlation between improved accommodative accuracy and slowed axial elongation was only observed during the first 6 months of treatment.

Treatment zone decentration promotes retinal reshaping in Chinese myopic children wearing orthokeratology lenses.

PURPOSE: To investigate whether the treatment zone (TZ) decentration in orthokeratology (OK) lenses affects retinal expansion in Chinese children with myopia. METHODS: Children aged 8 to 13 years (n = 30) were assessed over 13 months comprising 12 months of OK lens wear followed by discontinuation of lens wear for 1 month. Corneal topography was measured at 0, 1, 3, 6, 9, 12 and 13 months. TZ decentration of the OK lens was calculated, and subjects were subdivided into a small decentration group (group S) and a large decentration group (group L) based on the median value of the weighted average decentration (dave ). Central axial length (AL) and peripheral eye lengths (PELs) at the central retina, as well as 10°, 20° and 30° nasally and temporally were measured at 0 and 13 months under cycloplegia. Second-order polynomial (y = ax2 + bx + c) and linear fits (y = Kx + B) were applied to the peripheral relative eye length (PREL), and the coefficients 'a' and 'K' were used to describe the shape of the eye. RESULTS: Mean AL growth for one year was 0.28 ± 0.17 mm. In a multiple linear regression model, AL elongation was related to the baseline age (ß = -0.41, p = 0.01) and the dave (ß = -0.37, p = 0.03) (R2  = 0.34, p = 0.002). When compared with smaller dave (0.45 ± 0.15 mm), a larger dave (0.89 ± 0.17 mm) was associated with slower ocular growth (central: 0.20 ± 0.13 mm vs. 0.35 ± 0.17 mm, p = 0.009; 10° nasal: 0.26 ± 0.18 mm vs. 0.45 ± 0.21 mm, p = 0.02; 10° temporal: 0.17 ± 0.14 mm vs. 0.32 ± 0.19 mm, p = 0.02) and more oblate retina shape ('a': -0.13 ± 0.02 vs. -0.14 ± 0.02, p = 0.02; Knasal : 0.35 ± 0.11 vs. 0.39 ± 0.09, p = 0.02; Ktemporal : -0.42 ± 0.08 vs. -0.46 ± 0.08, p = 0.004). CONCLUSIONS: Greater TZ decentration with the use of OK lenses was associated with slower axial growth and a more oblate retinal shape. TZ decentration caused local defocusing changes, which may inhibit myopic progression. These findings may have important implications for improving optical designs for myopia control.

Intraperitoneal chromophore injections delay early-onset and rapid retinal cone degeneration in a mouse model of Leber congenital amaurosis.

Highly expressed in the retinal pigment epithelium (RPE), the RPE-specific 65-kDa (RPE65) enzyme is indispensable to generate 11-cis-retinal (11cRAL), a chromophore for rhodopsin and cone photopigments. RPE65 deficiency can lead to Leber congenital amaurosis type 2 (LCA2), in which the isomerization of photobleached all-trans-retinal into photosensitive 11cRAL is blocked, ultimately causing severe retinal dysfunction and degeneration. The related mouse models, which are constructed through gene knockout or caused by spontaneous mutations, morphologically present with early-onset and rapid retinal cone cells degeneration, including loss of short-wavelength-sensitive cone opsins (S-opsins) and mislocalization of medium-wavelength-sensitive cone opsins (M-opsins). Studies have shown that routine Rpe65 gene replacement therapy, mediated by an adeno-associated virus (AAV) vector, can restore RPE65 protein. However, AAV transfection and Rpe65 transgene expression require at least one to two weeks, and the treatment cannot fully block the early-onset cone degeneration. To determine the feasibility of delaying cone degeneration before gene therapy, we investigated the impact of 11cRAL treatment in an early-age LCA2 retinal degeneration 12 (rd12) mouse model. Similar to human patients, the mouse model carries a spontaneous mutation in the Rpe65 gene, which results in disrupted endogenous 11cRAL regeneration. We found that RPE65 deficiency did not notably affect rodent retinal vessels. Under red light illumination, the rd12 mice were intraperitoneally injected with exogenous 11cRAL from postnatal day (P) 14 to P21. Three days after the last injection, a notable recovery of retinal function was observed using scotopic and photopic electroretinograms. Using optical coherence tomography and histological analyses of the deficient retinas, we found changes in the thickness of the photoreceptor outer segment (OS); this change could be rescued by early 11cRAL treatment. In addition, the treatment notably preserved M- and S-opsins, both of which maintained appropriate localization inside cone cells, as shown by the wild-type mice. In contrast, the age-matched untreated rd12 mice were characterized by retinal S-opsin loss and M-opsin mislocalization from the photoreceptor OS to the inner segment, outer nuclear layer, or outer plexiform layer. Notably, 11cRAL treatment could not maintain retinal function for a long time. Ten days after the last injection, the rod and M-cone electroretinograms significantly decreased, and S-cone responses almost extinguished. Our findings suggest that early 11cRAL treatment is useful for restoring retinal function and rescuing morphology in the rd12 mouse model, and the early-onset and rapid cone degeneration can be delayed before gene therapy.

[Biopharmaceutical classification and transport mechanism of 4 alkaloids in Mongolian herbal medicine Sophorae Flavescentis Radix].

In this study, we studied the solubility and permeability of matrine, oxymatrine, sophoridine, and oxysophocarpine, four alkaloids in the Mongolian herbal medicine Sophorae Flavescentis Radix, and evaluated the absorption mechanism with the Caco-2 cell model, so as to provide a basis for the new drug development and efficacy evaluation of Sophorae Flavescentis Radix. The results showed that all the four alkaloids had high solubility and high permeability and can be well absorbed, belonging to the class-I drugs of Biopharmaceutical Classification System(BCS). The absorption(AP→BL) and excretion(BL→AP) of matrine and oxymatrine were not affected by the concentration while the absorption depended on P-gp protein. The absorption(AP→BL) and excretion(BL→AP) of sophoridine and oxysophocarpine were positively related to the concentration and time, and the absorption process was independent from P-gp protein. The results provide scientific reference and an experimental basis for the development of Mongolian medical prescriptions containing Sophorae Flavescentis Radix.

Rodent retinal microcirculation and visual electrophysiology following simulated microgravity.

How the absence of gravity affects the physiology of human beings is generating global research interest as space exploration, including missions aboard the International Space Station, continues to push boundaries. Here, we examined changes in retinal microcirculation and visual electrophysiology in mice suspended by their tails to simulate the cephalad movement of blood that occurs under microgravity conditions. Tail suspension was performed with a head-down tilt with a recommended angle of 30°. Mice in the control groups were similarly attached to a tether but could maintain a normal position. Morphologically, the 15-day tail-suspended mice showed retinal microvascular dilation, tortuosity, and a relatively long fluorescence retention; however, the average diameter of the major retinal vessels was not notably changed. In addition, optical coherence tomography showed their optic nerve head had an increased diameter. However, the mice could adapt to the change, with microcirculation and the optic nerve head recovering following 30-day tail suspension. Expression of rhodopsin and cone-opsins was not notably changed, and no retinal apoptotic-positive cells were detected between 15- and 30-day tail suspensions. Moreover, the three experimental groups of suspended mice showed normal retinal layers and thickness. Functionally, following 15-day tail suspension, scotopic electroretinograms showed a decline in the oscillatory potentials (OPs), but not in the b wave; simultaneously, the peak time of flash visual evoked potential component N1 was delayed compared to its baseline and the time-matched control. Following 30-day tail suspension, the OPs (O2) amplitude recovered to approximately 97% of its baseline or 86% of the time-matched control level. By simulating cephalad shifting of blood, short-term tail suspension can affect rodent retinal microcirculation, the optic nerve head, and disturb visual electrophysiology. However, the change is reversible with no permanent injury observed in the retina. The mice could adapt to the short-term change of retinal microcirculation, indicating new conditions that could be combined with, or could enhance, simulated microgravity for further studying the impact of short- or long-term outer space conditions on the retina.

Comparison of Near Addition Value Prescription Methods for Myopic Children.

PURPOSE: To compare personalized near addition values for myopic children that induce a reasonable phoria (Ph) (meeting Sheard's criterion) and induce a null lag of accommodation at near and to evaluate changes in these metrics after lens adaptation. METHODS: Fifty-three myopic children participated in this study. Accommodative response, Ph, and fusional amplitudes (FAs) were measured at 33 cm through multiple addition lenses (0D, +1.00D, +1.50D, +2.00D, +2.50D, +3.00D). The adaptation effect on measured parameters was evaluated after 6 min of near work with each addition. The FA/Ph ratios were calculated for each addition and fitted using a rational function to obtain the optimal addition value satisfying Sheard's criterion (FA/Ph ≥ 2). Lag of accommodation change in association with addition value was assessed using linear regressions to obtain the addition values inducing a null lag. RESULTS: Lag of accommodation (r = -0.987, p < 0.001) and Ph (r = -0.999, p < 0.001) decreased linearly with addition value. The 6-min adaptation induced a small but significant increase in accommodative lag and an exophoric shift (p < 0.05). Three FA/Ph patterns with respect to addition lenses were observed based on the near Ph: orthophoria/exophoria, low esophoria, and large esophoria. Addition values based on Sheard's criterion (mean ± SD, +2.16 ± 0.79D) were significantly lower than those based on null lag (+2.83 ± 0.44D, t = 19.86, p < 0.001). The FA/Ph ratio was less than 2.0 in 75.5% of subjects with additions determined through null accommodative lag. Additions determined through FA/Ph ≥ 2 induced a lag of accommodation of 0.38 ± 0.42D. CONCLUSIONS: Personalized near addition values using Sheard's criterion were lower than those obtained through null lag of accommodation. These values should allow a better binocular balance especially for exophoric children.

Influence of Near Tasks on Posture in Myopic Chinese Schoolchildren.

PURPOSE: To investigate near-vision posture in Chinese myopic schoolchildren and compare near-vision posture during different near-vision tasks (i.e., playing video games, reading, and writing). METHODS: The study investigated 120 myopic children (grades 1 through 6 and aged 6 to 13 years). An electromagnetic motion-tracking system was used for continuous measurements of the working distance and head declination of the subjects while they were playing video games or reading or writing at a desk. The reading and writing documents were adjusted by grade level (i.e., grades 1 to 2, 3 to 4, and 5 to 6). For analysis, the subjects were grouped in two refractive groups according to their median spherical equivalent refractive error (-1.50D). RESULTS: The myopic schoolchildren used close working distances for all tasks: 21.3 ± 5.2 cm (video games), 27.2 ± 6.4 cm (reading), and 24.9 ± 5.8 cm (writing). The mean head declinations were 63.5 ± 12.2 deg (video games), 37.1 ± 12.8 deg (reading), and 44.5 ± 14.1 deg (writing). Working distance decreased significantly across time for the reading and writing tasks (p < 0.001). Head declination increased significantly across time only for the reading task (p < 0.001). Grade level significantly influenced working distance, but the difference was not significant when working distance was adjusted by the subject's size. No differences were observed within the refractive or the accommodative lag groups in terms of the posture data (p > 0.05). Working distance was negatively correlated with head declination (r = -0.53, p < 0.001). CONCLUSIONS: Close working distances were observed for Chinese myopic schoolchildren. The attention dedicated to each task, the task difficulty, and the page/screen size may affect near working distance and head declination. Handheld video games were associated with the closest working distance, which may be a risk factor for myopia progression, according to previous studies.

Differential Impact of 0.01% and 0.05% Atropine Eyedrops on Ocular Surface in Young Adults.

Purpose: To evaluate the effect of low-concentration (0.01% and 0.05%) atropine eyedrops on ocular surface characteristics in young adults. Methods: Twenty-six myopic students aged 18 to 30 years were randomly assigned to receive either 0.01% or 0.05% atropine once nightly for 14 days, followed by cessation, with a ≥14-day interval between each administration. Assessments were conducted one, two, seven, and 14 days after using atropine with corresponding timepoints after atropine cessation. Tear meniscus height and first and average noninvasive keratograph tear film breakup time (NIKBUT-first, NIKBUT-average) were measured using Keratograph 5M, whereas the objective scatter index (OSI) was measured by OQAS II devices; the ocular surface disease index (OSDI) score was also obtained. Results: The mean OSI peaked after two days of administration of 0.05% atropine (ß = 0.51, P = 0.001), accompanied by significant decreases in NIKBUT-first (ß = -7.73, P < 0.001) and NIKBUT-average (ß = -8.10, P < 0.001); the OSDI peaked after 14 days (ß = 15.41, P < 0.001). The above parameters returned to baseline one week after atropine discontinuation (all P > 0.05). NIKBUT-first and NIKBUT-average reached their lowest points after 14 days of 0.01% atropine administration (NIKBUT-first: ß = -4.46, P = 0.005; NIKBUT-average: ß = -4.42, P = 0.001), but those significant changes were diminished once atropine treatment stopped. Conclusions: Young adult myopes experienced a significant but temporary impact on the ocular surface with 0.05% atropine administration, whereas 0.01% atropine had a minimal effect. Translational Relevance: The investigation of the ocular surface effects of different concentrations of atropine may inform evidence-based clinical decisions regarding myopia control in young adults.

Effect of spectacle lenses with aspherical lenslets on choroidal thickness in myopic children: a 3-year follow-up study.

BACKGROUND: To investigate the impact of wearing spectacle lenses with highly aspherical lenslets (HAL) for 3 years and the impact of switching from single-vision lenses (SVL) to HAL on choroidal thickness (ChT). METHODS: Fifty-one participants who had already worn HAL for 2 years continued wearing them for an additional year (HAL group). Further, 50 and 41 participants who had worn spectacle lenses with slightly aspherical lenslets (SAL) and SVL for 2 years, respectively, switched to wearing HAL for another year (SAL-HAL and SVL-HAL groups). Additionally, 48 new participants aged 10-15 years were enrolled to wear SVL at the third year (new-SVL group). ChT was measured every 6 months throughout the study. RESULTS: Significant differences were observed in the changes in ChT among the four groups at the third year (all P < 0.05 except for the outer nasal region: P = 0.09), with the new-SVL group showing larger reductions compared with the other three groups. However, none of the three HAL-wearing groups showed significant changes in ChT at the third year (all P > 0.05). When comparing the changes in ChT for 3 years among the HAL, SAL-HAL, and SVL-HAL groups, significant differences were found before switching to HAL, but these differences were abolished after all participants switched to HAL. CONCLUSIONS: Compared to those in the SVL group, choroid thinning was significantly inhibited in all the HAL groups. Wearing HAL for 3 years no longer had a choroidal thickening effect but could still inhibit choroidal thinning compared to wearing SVL. TRIAL REGISTRATION: The study was registered at the Chinese Clinical Trial Registry (ChiCTR1800017683), http://www.chictr.org.cn/showproj.aspx?proj=29789 .

Effect of spectacle lenses with aspherical lenslets on choroidal thickness in myopic children: a 2-year randomised clinical trial.

OBJECTIVE: Spectacle lenses with highly aspherical lenslets (HAL) and slightly aspherical lenslets (SAL) showed effective myopia control. This study was to investigate their effects on macular choroidal thickness (ChT) in myopic children. METHODS: Exploratory analysis from a 2-year, double-masked, randomised trial. 170 children aged 8-13 years with myopia between -0.75D and -4.75D, astigmatism of 1.50D or less, and anisometropia of 1.00D or less were recruited. Participants were randomly assigned in a 1:1:1 ratio to receive HAL, SAL or single vision spectacle lenses (SVL). The subfoveal, parafoveal and perifoveal ChT were evaluated every 6 months. RESULTS: 154 participants completed all examinations. The ChT showed significant changes over time in all three groups in all regions (all p<0.05). The ChTs continuously decreased in the SVL group (ranging from -20.75 (SD 22.34) µm to -12.18 (22.57) µm after 2 years in different regions). Compared with the SVL group, ChT in the SAL group decreased less (ranging from -16.49 (21.27) µm to -5.29 (18.15) µm). In the HAL group, ChT increased in the first year and then decreased in the second year (ranging from -0.30 (27.54) µm to 8.92 (23.97) µm after two years). The perifoveal ChT decreased less than the parafoveal ChT, and the superior region decreased the least. CONCLUSIONS: The ChT of the macula decreased after 2 years of myopia progression with SVL. Wearing spectacle lenses with aspherical lenslets reduced or abolished the ChT thinning and HAL had a more pronounced effect. TRIAL REGISTRATION NUMBER: ChiCTR1800017683.

Myopia Control Efficacy of Spectacle Lenses With Aspherical Lenslets: Results of a 3-Year Follow-Up Study.

PURPOSE: To investigate myopia control efficacy in children who continued wearing spectacle lenses with highly aspherical lenslets (HAL) or switched from spectacle lenses with slightly aspherical lenslets (SAL) and single-vision spectacle lenses (SVL) to HAL for 1 year after a 2-year myopia control trial. DESIGN: This was a 1-year extension of a randomized clinical trial. METHODS: Of 54 children who had worn HAL for 2 years, 52 continued wearing HAL (HAL1 group), and of the 53 and 51 children who had originally worn SAL or SVL, 51 and 48 switched to wearing HAL (HAL2 and HAL3 groups) in year 3, respectively. A new SVL (nSVL) group of 56 children was recruited, matched for age, sex, cycloplegic spherical equivalent refraction (SER), and axial length (AL) of the HAL3 group at extension baseline, and used for a comparison of third-year changes. SER and AL were measured every 6 months in year 3. RESULTS: During year 3, the mean (SE) myopia progression in the nSVL group was -0.56 (0.05) diopters (D). Compared with nSVL, the changes in SER were less in HAL1 (-0.38 [0.05] D, P = .02), HAL2 (-0.36 [0.06] D, P = .01), and HAL3 (-0.33 [0.06] D, P = .005). The mean (SE) AL elongation in the nSVL group was 0.28 (0.02) mm. Compared with nSVL, the elongation in AL was less in the HAL1 (0.17 [0.02] mm, P < .001), HAL2 (0.18 [0.02] mm, P < .001), and HAL3 (0.14 [0.02] mm, P < .001) groups. Myopia progression and axial elongation were comparable in all 3 HAL groups (all P > .05) in year 3. CONCLUSIONS: Myopia control efficacy has remained in children who wore HAL in the previous 2 years. Children who switched from SAL or SVL to HAL in year 3 had slower myopia progression and axial elongation than that in the control group.

Effects of Spectacle Lenses With Aspherical Lenslets on Peripheral Eye Length and Peripheral Refraction in Myopic Children: A 2-Year Randomized Clinical Trial.

Purpose: To investigate changes in peripheral eye length (PEL) and peripheral refraction (PR) in myopic children after wearing spectacle lenses with highly or slightly aspherical lenslets (HAL or SAL) for 2 years. Methods: We recruited 170 children aged 8 to 13 years with myopia between -0.75 diopters (D) and -4.75 D. Participants were randomized to wear HAL, SAL, or single vision spectacle lenses (SVL). PEL and PR were measured at 0° central and 15° and 30° in the nasal and temporal retina every 6 months for 2 years. The relative PR (RPR) was calculated by subtracting central from peripheral values. Results: PELs significantly increased with time (all P < 0.001), with the greatest elongation in the SVL group and the least in the HAL group. In the SVL and SAL groups, axial length elongated faster than the periphery. Whereas in the HAL group, N30 elongated faster than other PELs, axial length elongated less than the periphery. With time, the PR became more negative (all P < 0.001), with the most negative changes in the SVL group and the least negative changes in the HAL group. RPR became more hyperopic in the SVL and SAL groups, but less hyperopic in the HAL group (all P < 0.001). Conclusions: Over the 2-year myopia progression, steeper retina and greater peripheral hyperopic defocus were found in the SVL group. In the SAL group, changes were attenuated. In the HAL group, the retina flattened and peripheral defocus became less hyperopic. Translational Relevance: HAL and SAL lenses had little impact on PEL elongation.

An indirect method to compare the reference centres for corneal measurements.

PURPOSE: Corneal measurements are commonly presented with respect to a specific reference centre, but the location of the reference centre on the corneal surface could vary from one diagnostic modality to another. This study aimed to develop a method for comparing reference centres used by corneal measurement systems. METHODS: An indirect method was developed to compare reference centres by making use of the pupil centre and its offset from the reference centre. Reference centres in a Scheimpflug imaging system, the Pentacam HR, and a Placido-ring corneal topography system, the ATLAS Corneal Topography System, were compared for the right and left eyes of 30 subjects. The subjects all had similar pupil sizes when measured by the two systems. Differences and correlations of the pupil centre offsets between the two systems were statistically tested and compared by Bland-Altman analyses. RESULTS: There were no significant differences in mean pupil offsets between the two systems for either the right or left eyes (p > 0.05). There were strong correlations of the pupil centre offsets between the two systems for each eye (right eye x-axis: r = 0.95, p < 0.0001; right eye y-axis: r = 0.98, p < 0.0001; left eye x-axis: r = 0.96, p < 0.0001, left eye y-axis: r = 0.93, p < 0.0001). Bland-Altman analyses revealed no significant differences in pupil centre offsets between the two systems. CONCLUSIONS: The Pentacam HR system and the ATLAS system have very similar reference centres. Thus it is possible to directly analyze data from the Pentacam HR and other instruments using the corneal vertex or the pupil centre as the reference centres due to the similarity in the reference centre settings between the two systems.