Visual Acuity and Over-refraction in Myopic Children Fitted with Soft Multifocal Contact Lenses

Intraocular Straylight and Multifocal Soft Contact Lens Fit With a Myopia Control Approach

OBJECTIVES

Center-distance multifocal contact lenses (MFCLs) are used to slow myopia progression. We examined the effect of two MFCLs on intraocular straylight values in myopic individuals.

METHODS

Twenty-five young myopic adults were enrolled and were fit with three contact lenses (Biofinity sphere, Biofinity Multifocal, and NaturalVue Multifocal) in a random order over two study visits. Pupil size (NeurOptics VIP-300, Laguna Hills, CA) and contact lens centration were measured. Right eye intraocular straylight measurements were collected (OCULUS C-Quant; Wetzlar, Germany) and compared with a spectacle trial lens. Log straylight (LogSL) values and straylight residuals were analyzed using repeated-measures analyses of variance with Tukey-corrected post hoc t -tests.

RESULTS

The mean participant age (±SD) was 24.1±1.5 years, and right eye spherical equivalent refractive error was -3.38±1.53 DS. There was no difference in mesopic pupil size between visits ( P =0.68) and no difference in contact lens centration between lenses ( P =0.99). LogSL values differed by lens type ( P =0.004). LogSL with the spectacle trial lens was significantly greater than with each contact lens type (all P <0.05), but there were no significant differences in LogSL between the three contact lenses (all P >0.05). There was no difference between the three contact lens designs for straylight residuals ( P =0.33).

CONCLUSIONS

Measured intraocular straylight for both MFCLs was not different than with a spherical soft contact lens. A significant increase in intraocular straylight with spectacle trial lens correction was observed compared with all contact lenses.

Myopia control efficacy of peripheral defocus soft contact lenses in children and adolescents: A meta-analysis

OBJECTIVES

To evaluate the effect of peripheral defocus soft contact lenses (PDSCLs) on controlling myopia progression in children and adolescents, and to compare it with orthokeratology (Ortho-K) and single vision lenses (SVLs).

METHODS

We conducted a systematic search of PubMed, the Cochrane Library, Medline, CNKI, CBM, VIP, and WanFang Data databases for randomized controlled trials (RCTs) and cohort studies that investigated the effects of PDSCLs on myopia control in children and adolescents. The published languages were limited to English and Chinese. The risk bias tool provided by the Cochrane risk-of-bias tool and Newcastle-Ottawa Scale were used to assess the risk bias of included studies of RCTs and CTs. The published biases of included studies were assessed by Egger`s test.

RESULTS

We included 21 studies, comprising 13 RCTs and 8 cohort studies, with a total of 1337 participants in the PDSCLs group, 428 in the Ortho-K group, and 707 in the SVLs group. The meta-analysis indicated no significant difference between PDSCLs and Ortho-K in controlling the increase of diopter (MD = 0.01, 95% CI: -0.06, 0.09; P = 0.69) and axial length (MD = -0.01, 95% CI: -0.02, 0.00; P = 0.28). Compared with SVLs, PDSCLs had a better effect in controlling the increase of diopter (MD = 0.23, 95% CI: 0.17, 0.28; P < 0.00001) and axial length (MD = -0.11, 95% CI: -0.12, -0.09; P < 0.00001) in children and adolescents.

CONCLUSIONS

Children and adolescents wearing PDSCLs can achieve better myopia control than those wearing SVLs, and their effect is comparable to that of Ortho-K.

The effect of concentric and aspheric multifocal soft contact lenses on binocular vision in young adult myopes

PURPOSE

Multifocal soft contact lenses (MFCLs) are prescribed to inhibit myopia progression; these include aspheric and concentric designs. The effects of MFCLs on visual quality, accommodation and vergence in young-adult myopes were evaluated.

METHODS

Participants were twenty-six myopes (19-25 years, spherical equivalent -0.50 to -5.75D), with normal binocular vision and no past myopia control. Pupil sizes were 4.4 ± 0.9 mm during distance viewing and 3.7 ± 0.8 mm at near. In random order, participants wore four MFCLs: Proclear single vision distance, MiSight concentric dual focus (+2.00D), distance center aspheric (Biofinity, +2.50D) (CooperVision lenses), and NaturalVue aspheric (Visioneering Technologies). Testing included visual acuity, contrast sensitivity (Pelli-Robson), stereoacuity, accommodation response, negative and positive relative accommodation, horizontal phorias, horizontal fusional vergence and AC/A ratio, and a visual quality questionnaire.

RESULTS

The four lenses differed in distance (p = 0.001) and near visual acuity (p = 0.011), and contrast sensitivity (p = 0.001). Compared with the single vision lens, the Biofinity aspheric had the greatest visual impact: 0.19 ± 0.14 logMAR distance acuity reduction, 0.22 ± 0.15 log contrast sensitivity reduction. Near acuity was affected less than distance acuity; the reduction was greatest with the NaturalVue (0.05 ± 0.07 logMAR reduction). The MFCLs altered the autorefraction measure at distance and near (p = 0.001); the accommodation response was less with aspheric lenses. Negative relative accommodation reduced with the aspheric lenses (p = 0.001): by 0.9 ± 0.5D with Biofinity and 0.5 ± 0.7D with NaturalVue. Exophoric shifts were greater with aspheric lenses (1.8 ± 2.4Δ Biofinity, 1.7 ± 1.7Δ NaturalVue) than with the concentric MiSight (0.5 ± 1.3Δ).

CONCLUSIONS

MFCLs alter visual performance, refraction and vergence; two aspheric lenses had greater effect than a concentric lens.

Peripheral Defocus and Myopia Management: A Mini-Review

Myopia is the most common refractive error in the world, and its' prevalence continually increases. The potential pathological and visual complications of progressive myopia have inspired researchers to study the sources of myopia, axial elongation, and explore modalities to arrest progression. Considerable attention has been given over the past few years to the myopia risk factor known as hyperopic peripheral blur, the focus of this review. The primary theories currently believed to be the cause of myopia, the parameters considered to contribute and influence the effect of peripheral blur, such as the surface retinal area or depth of blur will be discussed. The currently available optical devices designed to provide peripheral myopic defocus will be discussed, including bifocal and progressive addition ophthalmic lenses, peripheral defocus single vision ophthalmic lenses, orthokeratology lenses, and bifocal or multifocal center distance soft lenses, as well as their effectivity as mentioned in the literature to date.

Clinical Outcomes of a Randomized Trial with Contact Lenses for Astigmatic Myopia Management

SIGNIFICANCE

There are limited treatment options for myopia management of patients with moderate to high astigmatism. This work directly compares toric orthokeratology and soft toric multifocal lenses to show differences in visual acuity and patient satisfaction that could impact clinical care. Toric orthokeratology caused reduced visual acuity but was preferred subjectively for vision and overall.

PURPOSE

This study aimed to quantify objective and subjective clinical differences between toric orthokeratology and soft toric multifocal contact lenses in the same cohort of myopic wearers with moderate to high astigmatism.

METHODS

Thirty adults with refractive myopia (plano to -5.00 D) and astigmatism (1.25 to 3.50 D) were fitted empirically with both toric orthokeratology and soft toric multifocal contact lenses. Participants wore lenses for 10 days in random order, separated by a 14-day washout period. High-contrast visual acuity, low-contrast visual acuity, and glare logMAR visual acuity were measured. Surveys ascertained subject preference for comfort, vision, handling, and cost. Friedman, Wilcoxon signed rank, and χ2 tests were performed.

RESULTS

A subset of participants (n = 17) who achieved good vision with both lens types was analyzed. High-contrast and glare acuity with toric orthokeratology were reduced by one line compared with soft toric multifocal lenses (both 0.00 vs. -0.10, P ≤ .003). Participants preferred toric orthokeratology for vision ( P ≤ .03) but soft toric multifocal lenses for handling ( P ≤ .006). When forced to choose between lens types, participants preferred toric orthokeratology for vision and overall (both P ≤ .007).

CONCLUSIONS

Participants who achieved good vision with both lens types preferred toric orthokeratology over soft toric multifocal lenses, despite reduced high-contrast and glare visual acuity. Further research is needed to understand the relationship between visual performance and patient satisfaction.

Randomized Trial of Soft Contact Lenses with Novel Ring Focus for Controlling Myopia Progression

Purpose

To evaluate efficacy and vision with 2 prototype myopia control soft contact lenses with noncoaxial ring-focus designs (for enhancing efficacy [EE] and enhancing vision [EV]) compared with dual-focus (DF) and single-vision (SV) designs.

Design

Multicenter, 6-month, randomized, controlled, double-masked clinical trial.

Participants

One hundred ninety-nine myopic (-0.75 diopters [D] to -4.50 D) children aged 7 to 12 years.

Methods

Participants were randomized with stratification into myopia control (EE, EV, or DF) or SV arms at 9 clinical sites in 3 countries. Postcycloplegia axial length (AL) and spherical equivalent autorefraction (SECAR) were measured at baseline and 26 weeks. Axial length was also measured without cycloplegia at baseline, 1, 4, 13, and 26 weeks. Progression was analyzed using linear mixed models by intention-to-treat population. Visual acuity (VA) and vision quality were monitored.

Main Outcome Measures

Axial elongation, change in SECAR.

Results

A total of 185 subjects completed the study (n = 44, 49, 45, and 47 for EE, EV, DF, and SV, respectively). There were no serious/significant ocular adverse events. After 26 weeks, EE, EV, and DF all had statistically significantly less axial elongation than SV (unadjusted mean [standard deviation]: EE, 0.079 [0.125]; EV, 0.119 [0.101]; DF, 0.135 [0.117]; SV; 0.189 [0.121] mm). The estimated least-square mean (LSM) differences (adjusted 95% confidence interval) compared with SV were -0.105 (-0.149, -0.062), -0.063 (-0.106, -0.020), and -0.056 (-0.100, -0.013) mm for EE, EV, and DF, respectively. Enhancing efficacy alone had statistically significantly less progression of SECAR than SV (EE: -0.12 [0.27] D vs. SV: -0.35 [0.33] D; LSM difference: 0.22 D [0.09, 0.35]). Enhancing efficacy also had statistically significantly less axial elongation than DF (-0.049 mm [-0.093, -0.004]). Changes in AL and SECAR of EV and DF were not statistically different. All 3 myopia control lenses had mean VA close to 0.00 logarithm of the minimum angle of resolution (logMAR) with estimated 95% upper confidence limits <0.10 logMAR. Enhancing efficacy and DF produced similar reports of halos but more than EV and SV.

Conclusions

The prototype contact lenses met the design intent; EE was more efficacious in slowing axial elongation than DF with comparable vision performance, whereas EV produced comparable efficacy to DF with similar vision performance to SV.

Visual performance with multifocal corneal gas-permeable contact lenses in young adults: A pilot study

OBJECTIVES

To evaluate the performance of four experimental multifocal gas permeable contact lens (MFGPCL) designs and their impact on visual function in young adults.

METHODS

Seventeen young adults (age, 23.17 ± 4.48 years) enrolled in the study. Each participant was randomly assigned to wear two of four MFGPCL designs. They wore the first type of the assigned lens binocularly for one week and, after one week of washout period, wore another design on both eyes for another week. The four MFGPCL designs were as follows: design A (distance zone [DZ] 1.5 mm / add 3.0 D), B (DZ 1.5 mm / add 1.5 D), C (DZ 3.0 mm / add 3.0 D), and D (DZ 3.0 mm / add 1.5 D). Baseline visual acuity, contrast sensitivity function, and accommodation data were collected at baseline and repeated after one week of MFGPCL daily wear.

RESULTS

Distance and near visual acuities were not significant affected with the four MFGPCL designs. Contrast sensitivity was significantly lower in design A across all measured spatial frequencies (p < 0.05), with no significant impact from other designs on all frequencies. No significant effect was observed on accommodation measured at 33 cm (p > 0.05).

CONCLUSIONS

Three of the investigated MFGPCL designs preserve satisfactory visual performance. Lens design A incorporated with higher add and smaller center zone diameter had a stronger impact on the visual performance.

Contrast Sensitivity with Center-distance Multifocal Soft Contact Lenses

SIGNIFICANCE

The contrast sensitivity (CS) function provides a more detailed assessment of vision than visual acuity. It was found that center-distance multifocal contact lens designs that are increasingly being prescribed for myopia control reduce distance photopic and mesopic CS in nonpresbyopic patients across a range of spatial frequencies.

PURPOSE

This study aimed to determine the effect of center-distance multifocal soft contact lenses (MFCLs) on CS under photopic and mesopic conditions in nonpresbyopic patients.

METHODS

Twenty-five myopic, nonpresbyopic adults were fitted binocularly with three lenses: Biofinity single vision contact lens (SVCL), Biofinity Multifocal D +2.50 add, and NaturalVue Multifocal in random order. Contrast sensitivity was measured at distance (4 m) under photopic and mesopic conditions and at near under photopic conditions. Log CS by spatial frequency and area under the log contrast sensitivity function (AULCSF) were analyzed between lenses.

RESULTS

Distance photopic CS at each spatial frequency was higher with the SVCL than the MFCLs (P < .001), but there was no difference between the MFCLs (P = .71). Distance mesopic CS from 1.5 to 12 cycles per degree (cpd) was higher with the SVCL than the MFCLs (all P < .02); however, at 18 cpd, there was no difference in CS between NaturalVue and the SVCL (P = .76), possibly because of spurious resolution. Photopic AULCSF for the SVCL was roughly 10% greater than both MFCLs. Contrast sensitivity at near was generally similar between lenses, only slightly lower with the NaturalVue at 11 and 15.5 cpd, but AULCSF at near was not different between lenses (P > .05).

CONCLUSIONS

Multifocal contact lenses reduce distance contrast sensitivity under both photopic and mesopic conditions. There is no clinically significant difference in near CS among all three lenses. These data show that MFCLs have effects on vision that are not captured by standard high-contrast visual acuity testing.

Vision-related quality of life with myopia management: A review

The disease of myopia has come into focus as a worldwide public health concern. Myopia has shown increasing prevalence, incidence at earlier age and progression to a higher degree. Progressive increase in degree of myopia is strongly associated with increase in axial length of the eye. Various interventions have been shown to slow axial elongation in children. These interventions have been studied to assess efficacy in slowing axial elongation and correction of vision. In addition, research into quality of vision, risk of adverse events, overall safety and impact on vision-related quality (VR-QoL) of life has been pursued. In contrast, studies have been published to demonstrate the risks of myopia, high myopia and increased axial length. This review will discuss VR-QoL assessment on the most effective and most commonly prescribed interventions to slow axial elongation and myopia progression. The patient attributes considered are VR-QoL scores from validated instruments. The development and use of validated survey instruments to assess the patient-reported outcomes is discussed. The review demonstrates that there are numerous factors that may impact VR-QoL to evaluate in the decision-making process when eye care providers consider when, how and if to prescribe myopia management (MM) for children with myopia.

The Effects of Center-near and Center-distance Multifocal Contact Lenses on Peripheral Defocus and Visual Acuity

SIGNIFICANCE

Multifocal contact lenses (MFCLs) are being used clinically for myopia control. Center-distance designs caused myopic changes in defocus across the retina that varied by lens design, whereas the center-near design caused peripheral hyperopic changes. Multifocal lenses caused reductions in low-contrast vision that varied by lens design, affecting visual performance.

PURPOSE

The purpose of this study was to compare changes in defocus with four MFCLs, three center-distance and one center-near.

METHODS

Two cohorts of 25 nonpresbyopic myopic adults were enrolled. The first cohort was fitted with Proclear D and Biofinity D MFCL (center-distance, +2.50 D add), and the second cohort was fitted with NaturalVue MFCL (center-distance) and Clariti 1-Day MFCL (center-near, high add), both in random order. Overrefraction was performed to maximize visual acuity. Cycloplegic autorefraction was performed with each lens and without a lens along the line of sight and at nasal and temporal retinal locations out to 40°. Data were analyzed with repeated-measures ANOVAs with post hoc t tests, when indicated.

RESULTS

Changes in defocus at each location differed between MFCL designs (lens by location; both, P < .001). Clariti 1-Day caused peripheral hyperopic retinal changes (40 and 30° nasal, and 20, 30, and 40° temporal; all, P < .05). NaturalVue MFCL caused myopic changes centrally and hyperopic changes at 40° nasal and 30° temporal (all, P < .05). The remaining center-distance designs caused myopic changes at multiple locations (all, P < .05).

CONCLUSIONS

After overrefraction, the center-near MFCL design caused hyperopic defocus at multiple peripheral locations, which is not hypothesized to slow myopia progression. NaturalVue MFCL caused myopic changes in defocus centrally but hyperopic changes in the far periphery. Biofinity D and Proclear D caused myopic changes in retinal defocus. Further work is warranted to determine whether defocus profile differences between the center-distance designs influence any slowing of myopia progression.

IMI Prevention of Myopia and Its Progression

The prevalence of myopia has markedly increased in East and Southeast Asia, and pathologic consequences of myopia, including myopic maculopathy and high myopia-associated optic neuropathy, are now some of the most common causes of irreversible blindness. Hence, strategies are warranted to reduce the prevalence of myopia and the progression to high myopia because this is the main modifiable risk factor for pathologic myopia. On the basis of published population-based and interventional studies, an important strategy to reduce the development of myopia is encouraging schoolchildren to spend more time outdoors. As compared with other measures, spending more time outdoors is the safest strategy and aligns with other existing health initiatives, such as obesity prevention, by promoting a healthier lifestyle for children and adolescents. Useful clinical measures to reduce or slow the progression of myopia include the daily application of low-dose atropine eye drops, in concentrations ranging between 0.01% and 0.05%, despite the side effects of a slightly reduced amplitude of accommodation, slight mydriasis, and risk of an allergic reaction; multifocal spectacle design; contact lenses that have power profiles that produce peripheral myopic defocus; and orthokeratology using corneal gas-permeable contact lenses that are designed to flatten the central cornea, leading to midperipheral steeping and peripheral myopic defocus, during overnight wear to eliminate daytime myopia. The risk-to-benefit ratio needs to be weighed up for the individual on the basis of their age, health, and lifestyle. The measures listed above are not mutually exclusive and are beginning to be examined in combination.

Visual Performance of Center-distance Multifocal Contact Lenses Fit Using a Myopia Control Paradigm

PURPOSE

The purpose of this study was to examine the visual performance of center-distance MFCLs in nonpresbyopic adults under different illumination and contrast conditions compared with a single-vision contact lens (SVCL).

METHODS

Twenty-five adult subjects were fit with three different lenses (CooperVision Biofinity D MFCL +2.50 add, Visioneering Technologies NaturalVue MFCL, CooperVision Biofinity sphere). Acuity and reading performance were evaluated.

RESULTS

A statistically significant difference in high-contrast distance acuity was observed (Biofinity, -0.18 ± 0.06; Biofinity MFCL, -0.14 ± 0.08; NaturalVue MFCL, -0.15 ± 0.03; repeated-measures [RM] ANOVA, P = .02). Under mesopic, high-contrast conditions, MFCLs performed worse than SVCLs (Biofinity, -0.05 ± 0.091; Biofinity MFCL, +0.03 ± 0.09; NaturalVue MFCL, +0.05 ± 0.091; RM-ANOVA, P < .0001). Under low-contrast conditions, MFCLs performed one line worse in photopic lighting and two lines worse under mesopic conditions (RM-ANOVA, P < .0001). Glare reduced acuity by 0.5 logMAR for all lenses (RM-ANOVA, P < .001). A statistically significant difference in near acuity was observed (RM-ANOVA, P = .02), but all lenses achieved acuity better than -0.1 logMAR (Biofinity, -0.16 ± 0.06; Biofinity MFCL, -0.17 ± 0.04; NaturalVue MFCL, -0.13 ± 0.08). Reading performance in words per minute (wpm) was worse with MFCLs (Biofinity MFCL, 144 ± 22 wpm; NaturalVue MFCL, 150 ± 28 wpm) than with SVCLs (156 ± 23 wpm; RM-ANOVA, P = .02) regardless of letter size (RM-ANOVA, P = .13). No difference in acuity between the MFCLs was detected (RM-ANOVA: all, P > .05).

CONCLUSIONS

Multifocal contact lenses perform similarly to SVCLs for high-contrast targets and display reduced low-contrast acuity and reading speed. Practitioners should recognize that high-contrast acuity alone does not describe MFCL visual performance.

Exploring non-adherence to contact lens wear schedule: Subjective assessments and patient related factors in children wearing single vision and myopia control contact lenses

PURPOSE

To determine factors associated with non-adherence to contact lens wear schedule involving single vision and myopia control contact lenses in children.

METHODS

Data from 379 children enrolled in a prospective, double masked, randomized clinical trial, aged 8-13 years, cycloplegic spherical equivalent of -0.75 to -3.50D and wearing either: single vision silicone hydrogel (SiH) CL (control lens); two anti-myopia SiH CL that incorporated relative plus in the central and periphery in a stepped manner (test lens I and II); and two extended depth of focus hydrogel CL (test lens III and IV) was considered. A questionnaire was administered to the participants at every scheduled visit and gathered information on days of wear/week and subjective assessments of ocular comfort and visual quality on an analog scale of 1-10.Participants were categorized as "Adherent" when lens wear was ≥ 6 days/week or "Non-adherent" when lens wear ≤ 5 days/week. Categorized adherence data was summarized as a percentage across visits for each CL type. Differences between the two groups were analyzed using linear mixed model.

RESULTS

For the control lens, 79.6 % participants were adherent as compared to 63.7%-74.6% with test lenses (p=0.026). Non-adherence was greater in those that discontinued (p<0.001). Subjective ratings of visual quality for static and dynamic tasks were lower with non-adherent wearers and more variable between visits. Ocular comfort was also poorer in non-adherent wearers irrespective of lens material or lens design. Male gender, lower baseline myopia, lower high contrast visual acuity and esophoria were associated with a higher risk of non-adherence.

CONCLUSIONS

The study identified a wide range of factors associated with non-adherence to lens wear schedule. Paying specific attention to these factors when evaluating patients for CL wear and taking steps to ensure satisfaction in lens wear may promote longer term continuation of wear.

Higher-Order Aberrations and Axial Elongation in Myopic Children Treated With Orthokeratology

Purpose

This retrospective longitudinal study aimed to examine the relationship between ocular higher-order aberrations (HOA) and axial eye growth in young myopic children undergoing orthokeratology (ortho-k) treatment.

Methods

Axial length and ocular HOA, measured under cycloplegia annually over a 2-year period from the right eyes of myopic children, who previously completed ortho-k clinical trials, were retrieved. Linear mixed model analyses were applied to determine the association between ocular HOA, other known confounding variables (age, sex, and refractive error), and axial eye growth.

Results

Data from 103 subjects were analyzed. The root-mean square (RMS) values of total ocular HOA (third to sixth orders combined), spherical (Z40 and Z60 combined), and comatic (Z3-1, Z31, Z5-1, and Z51 combined) aberrations increased by approximately 3, 9, and 2 times, respectively, after 2 years of ortho-k treatment. After adjusting for age, sex, and refractive error, higher RMS values of total HOA and spherical aberrations were associated with both longer axial length and slower axial elongation (all P < 0.01). For individual Zernike term coefficients, a higher level of positive spherical aberration (Z40) was also associated with longer axial length and slower axial elongation (both P < 0.01), after adjusting for baseline HOA.

Conclusions

Ortho-k for myopia control significantly increases the Zernike coefficients and therefore the RMS values for a range of total ocular HOA terms or metrics in children. These findings suggest the potential role of HOA, particularly spherical aberration, as the possible mechanism of slowing axial elongation in ortho-k treatment.

Bifocal & Atropine in Myopia Study: Baseline Data and Methods

SIGNIFICANCE

The Bifocal & Atropine in Myopia (BAM) study aims to determine whether combining 0.01% atropine and +2.50-diopter add center-distance soft bifocal contact lenses (SBCL) slows myopia progression more than SBCL alone. The results could provide significant information on the myopia control effect of combining optical and pharmacological treatments.

PURPOSE

This article describes the subject characteristics at baseline, the study methods, and the short-term effects of this combination treatment on visual acuity (VA) and vision-related outcomes.

METHODS

Subjects from the BAM study who met the baseline eligibility criteria were dispensed the combination treatment for 2 weeks to determine final eligibility. Outcome measures included VA at near and distance (Bailey-Lovie logMAR charts), near phoria (modified Thorington), accommodative lag (Grand Seiko WAM-5500), and pupil size (NeurOptics VIP-200 Pupillometer). Compliance was monitored using surveys. Two subgroups in the Bifocal Lenses In Nearsighted Kids study, single-vision contact lens wearers and those who wore +2.50-diopter add SBCL, will serve as the age-matched historical controls for BAM study.

RESULTS

Forty-nine BAM subjects (9.6 ± 1.4 years) were enrolled; mean spherical equivalent cycloplegic autorefraction was -2.33 ± 1.03 diopters. After 2 weeks of treatment, the best-corrected low-contrast (10% Michelson) distance VA was reduced (pre-treatment, +0.09 ± 0.07; post-treatment, +0.16 ± 0.08; P < .0001), but the high-contrast VA at near or distance was unaffected. Near phoria increased by approximately 2 in the exo direction (P = .01), but the accommodative lag was unchanged. The pupil size was not significantly different between pre-treatment and post-treatment of either the photopic or mesopic condition. Surveys indicated that the subjects wore SBCL 77 ± 22% of waking hours and used atropine 6.4 ± 0.7 days per week.

CONCLUSIONS

Two weeks of combination treatment reduced low-contrast distance VA and increased near exophoria slightly, but the subjects were compliant and tolerated the treatment well.

Interventions to slow progression of myopia in children

BACKGROUND

Nearsightedness (myopia) causes blurry vision when one is looking at distant objects. Interventions to slow the progression of myopia in children include multifocal spectacles, contact lenses, and pharmaceutical agents.

OBJECTIVES

To assess the effects of interventions, including spectacles, contact lenses, and pharmaceutical agents in slowing myopia progression in children.

SEARCH METHODS

We searched CENTRAL; Ovid MEDLINE; Embase.com; PubMed; the LILACS Database; and two trial registrations up to February 2018. A top up search was done in February 2019.

SELECTION CRITERIA

We included randomized controlled trials (RCTs). We excluded studies when most participants were older than 18 years at baseline. We also excluded studies when participants had less than -0.25 diopters (D) spherical equivalent myopia.

DATA COLLECTION AND ANALYSIS

We followed standard Cochrane methods.

MAIN RESULTS

We included 41 studies (6772 participants). Twenty-one studies contributed data to at least one meta-analysis. Interventions included spectacles, contact lenses, pharmaceutical agents, and combination treatments. Most studies were conducted in Asia or in the United States. Except one, all studies included children 18 years or younger. Many studies were at high risk of performance and attrition bias. Spectacle lenses: undercorrection of myopia increased myopia progression slightly in two studies; children whose vision was undercorrected progressed on average -0.15 D (95% confidence interval [CI] -0.29 to 0.00; n = 142; low-certainty evidence) more than those wearing fully corrected single vision lenses (SVLs). In one study, axial length increased 0.05 mm (95% CI -0.01 to 0.11) more in the undercorrected group than in the fully corrected group (n = 94; low-certainty evidence). Multifocal lenses (bifocal spectacles or progressive addition lenses) yielded small effect in slowing myopia progression; children wearing multifocal lenses progressed on average 0.14 D (95% CI 0.08 to 0.21; n = 1463; moderate-certainty evidence) less than children wearing SVLs. In four studies, axial elongation was less for multifocal lens wearers than for SVL wearers (-0.06 mm, 95% CI -0.09 to -0.04; n = 896; moderate-certainty evidence). Three studies evaluating different peripheral plus spectacle lenses versus SVLs reported inconsistent results for refractive error and axial length outcomes (n = 597; low-certainty evidence). Contact lenses: there may be little or no difference between vision of children wearing bifocal soft contact lenses (SCLs) and children wearing single vision SCLs (mean difference (MD) 0.20D, 95% CI -0.06 to 0.47; n = 300; low-certainty evidence). Axial elongation was less for bifocal SCL wearers than for single vision SCL wearers (MD -0.11 mm, 95% CI -0.14 to -0.08; n = 300; low-certainty evidence). Two studies investigating rigid gas permeable contact lenses (RGPCLs) showed inconsistent results in myopia progression; these two studies also found no evidence of difference in axial elongation (MD 0.02mm, 95% CI -0.05 to 0.10; n = 415; very low-certainty evidence). Orthokeratology contact lenses were more effective than SVLs in slowing axial elongation (MD -0.28 mm, 95% CI -0.38 to -0.19; n = 106; moderate-certainty evidence). Two studies comparing spherical aberration SCLs with single vision SCLs reported no difference in myopia progression nor in axial length (n = 209; low-certainty evidence). Pharmaceutical agents: at one year, children receiving atropine eye drops (3 studies; n = 629), pirenzepine gel (2 studies; n = 326), or cyclopentolate eye drops (1 study; n = 64) showed significantly less myopic progression compared with children receiving placebo: MD 1.00 D (95% CI 0.93 to 1.07), 0.31 D (95% CI 0.17 to 0.44), and 0.34 (95% CI 0.08 to 0.60), respectively (moderate-certainty evidence). Axial elongation was less for children treated with atropine (MD -0.35 mm, 95% CI -0.38 to -0.31; n = 502) and pirenzepine (MD -0.13 mm, 95% CI -0.14 to -0.12; n = 326) than for those treated with placebo (moderate-certainty evidence) in two studies. Another study showed favorable results for three different doses of atropine eye drops compared with tropicamide eye drops (MD 0.78 D, 95% CI 0.49 to 1.07 for 0.1% atropine; MD 0.81 D, 95% CI 0.57 to 1.05 for 0.25% atropine; and MD 1.01 D, 95% CI 0.74 to 1.28 for 0.5% atropine; n = 196; low-certainty evidence) but did not report axial length. Systemic 7-methylxanthine had little to no effect on myopic progression (MD 0.07 D, 95% CI -0.09 to 0.24) nor on axial elongation (MD -0.03 mm, 95% CI -0.10 to 0.03) compared with placebo in one study (n = 77; moderate-certainty evidence). One study did not find slowed myopia progression when comparing timolol eye drops with no drops (MD -0.05 D, 95% CI -0.21 to 0.11; n = 95; low-certainty evidence). Combinations of interventions: two studies found that children treated with atropine plus multifocal spectacles progressed 0.78 D (95% CI 0.54 to 1.02) less than children treated with placebo plus SVLs (n = 191; moderate-certainty evidence). One study reported -0.37 mm (95% CI -0.47 to -0.27) axial elongation for atropine and multifocal spectacles when compared with placebo plus SVLs (n = 127; moderate-certainty evidence). Compared with children treated with cyclopentolate plus SVLs, those treated with atropine plus multifocal spectacles progressed 0.36 D less (95% CI 0.11 to 0.61; n = 64; moderate-certainty evidence). Bifocal spectacles showed small or negligible effect compared with SVLs plus timolol drops in one study (MD 0.19 D, 95% CI 0.06 to 0.32; n = 97; moderate-certainty evidence). One study comparing tropicamide plus bifocal spectacles versus SVLs reported no statistically significant differences between groups without quantitative results. No serious adverse events were reported across all interventions. Participants receiving antimuscarinic topical medications were more likely to experience accommodation difficulties (Risk Ratio [RR] 9.05, 95% CI 4.09 to 20.01) and papillae and follicles (RR 3.22, 95% CI 2.11 to 4.90) than participants receiving placebo (n=387; moderate-certainty evidence).

AUTHORS' CONCLUSIONS

Antimuscarinic topical medication is effective in slowing myopia progression in children. Multifocal lenses, either spectacles or contact lenses, may also confer a small benefit. Orthokeratology contact lenses, although not intended to modify refractive error, were more effective than SVLs in slowing axial elongation. We found only low or very low-certainty evidence to support RGPCLs and sperical aberration SCLs.

Contrast sensitivity and visual acuity in subjects wearing multifocal contact lenses with high additions designed for myopia progression control

OBJECTIVES

To assess the visual performance of multifocal contact lenses (MFCLs) with high addition powers designed for myopia control.

METHODS

Twenty-four non-presbyopic adults (mean age 24 years, range 18-36 years) were fitted with soft MFCLs with add powers of +2.0 D (Add2) and +4.0 D (Add4) (RELAX, SwissLens) and single vision lenses (SVCL; Add0) in a counterbalanced order. In this double-masked study, half of the participants were randomly fitted with 3 mm-distance central zone MFCLs while the other half received 4.5 mm-distance central zone MFCLs. Visual acuity was measured at distance (3.0 m) and at near (0.4 m). Central and peripheral contrast sensitivity was evaluated at distance using the Gabor patch test. The area under the logarithmic contrast sensitivity function curve (ALCSF) was calculated and compared between the groups (i.e. different additions powers used).

RESULTS

Near and distance visual acuities were not affected by the lenses, neither Add2 nor Add4, when compared to Add0, however, CZ3 significantly reduced distance visual acuity with Add4 when compared to CZ4.5 (-0.08 logMAR vs. for CZ3 and -0.18 logMAR for CZ4.5, p = 0.013). MFCLs impaired central ALCSF only when Add2 was used (15.99 logCS for Add2 and 16.36 logCS for SVCLs, p = 0.021). Peripheral ALCSF was statistically lower for both addition powers of the MFCLs when compared to SVCLs (12.70 for Add2 and Add4, 13.73 for SVCLs, p = 0.009). The above effects were the same for both central zones used.

CONCLUSIONS

MFCLs with CZ3 diameter and high add power (Add4) slightly reduced distance visual acuity when compared to CZ4.5 but no reduction in this parameter was found with medium add power (Add2). Central contrast sensitivity was impaired only by MFCLs with the lower add power (Add2). Both add powers in the MFCLs reduced peripheral contrast sensitivity to a similar extent.

IMI - Clinical Management Guidelines Report

Best practice clinical guidelines for myopia control involve an understanding of the epidemiology of myopia, risk factors, visual environment interventions, and optical and pharmacologic treatments, as well as skills to translate the risks and benefits of a given myopia control treatment into lay language for both the patient and their parent or caregiver. This report details evidence-based best practice management of the pre-, stable, and the progressing myope, including risk factor identification, examination, selection of treatment strategies, and guidelines for ongoing management. Practitioner considerations such as informed consent, prescribing off-label treatment, and guides for patient and parent communication are detailed. The future research directions of myopia interventions and treatments are discussed, along with the provision of clinical references, resources, and recommendations for continuing professional education in this growing area of clinical practice.

Simulated optical performance of soft contact lenses on the eye

PURPOSE

To evaluate the impact of soft contact lens eye-fit on optical power by computational modelling and to produce correction maps for reversing this impact during the design process.

METHODS

Finite element models of spherical and toric hydrogel contact lenses at varying nominal powers of -20 D to +20 D, base curves radii (R1b) of 8.2, 8.5, 8.8 mm, and overall diameters (d3) of 14.5, 15.0, 15.5 mm were generated. Lenses were fitted to computational eye models generated with human eyes' topography data. Combined eye-lens simulations were run under the boundary conditions of the tears' surface tension between the contact lens and the eye in addition to the eyelid blink pressure. Lens optical zone power changes were calculated through computational light-ray tracing methods following each simulation.

RESULTS

Effective power changes (EPC) were affected negatively for all toric simulated lenses with power varying from -20 D to +20 D. Spherical lenses demonstrated similar behaviour, however with some positive EPC over the power range from -20 D to -10 D for spherical power (SPH) lenses. EPC assessment was between +0.25 D and -0.5 D for most lenses, however, lenses with prescriptions from +10 D to +20 D incurred EPC outside this range. The spherical lenses showed a maximum effective power change of +1.046 ± 0.338 D (Average Eye), and a minimum of -3.278 ± 0.731 D (Steep Eye). Similarly, the toric lenses showed a maximum of +1.501 ± 0.338 D (Average Eye), and a minimum of -3.514 ± 0.731 D (Steep Eye). EPC trends, along with minimum and maximum power, generally increased negatively as nominal lens prescription increased positively. Contact lens base curve selection affected the assessed effective power change for both spherical and toric lenses. The effect from lens total diameter for spherical lenses was less substantial than that for toric lenses.

CONCLUSIONS

This study considered the impact of soft contact lens design parameters on effective optical power changes (EPC) after eye-fit. Spherical lenses experienced more EPC of clinical significance (>0.25 D) than toric lenses. Both types of lenses, spherical and toric (simple astigmatism), demonstrated similar trends in EPC on fitting from -20 D to +20 D, with lenses in the extremely positive and the extremely negative prescriptions demonstrating the highest EPCs. The lens base curve impacted the extent of EPC observed, with flatter base curves experiencing less power change. Diameter proved to impact toric lenses more than spherical ones, however generally the diameter has less effect on power change than base curve selection.