Clinical management of progressive myopia

A wireless battery-free eye modulation patch for high myopia therapy

The proper axial length of the eye is crucial for achieving emmetropia. In this study, we present a wireless battery-free eye modulation patch designed to correct high myopia and prevent relapse. The patch consists of piezoelectric transducers, an electrochemical micro-actuator, a drug microneedle array, μ-LEDs, a flexible circuit, and biocompatible encapsulation. The system can be wirelessly powered and controlled using external ultrasound. The electrochemical micro-actuator plays a key role in precisely shortening the axial length by driving the posterior sclera inward. This ensures accurate scene imaging on the retina for myopia eye. The drug microneedle array delivers riboflavin to the posterior sclera, and μ-LEDs' blue light induces collagen cross-linking, reinforcing sclera strength. In vivo experiments demonstrate that the patch successfully reduces the rabbit eye's axial length by ~1217 μm and increases sclera strength by 387%. The system operates effectively within the body without the need for batteries. Here, we show that the patch offers a promising avenue for clinically treating high myopia.

Low-intensity, long-wavelength red light slows the progression of myopia in children: an Eastern China-based cohort

PURPOSE

To determine the effect of low-intensity, long-wavelength red light therapy (LLRT) on the inhibition of myopia progression in children.

METHODS

A retrospective study was conducted. One hundred and five myopic children (spherical equivalent refractive error [SER] -3.09 ± 1.74 dioptres [D]; mean age, 9.19 ± 2.40 years) who underwent LLRT treatment (power 0.4 mW, wavelength 635 nm) twice per day for 3 min each session, with at least a 4-h interval between sessions, and a control group of 56 myopic children (SER -3.04 ± 1.66 D; mean age, 8.62 ± 2.45 years) were evaluated. Both groups wore single-vision distance spectacles. Each child returned for a follow-up examination every 3 months after the initial measurements for a total of 9 months.

RESULTS

At 9 months, the mean SER in the LLRT group was -2.87 ± 1.89 D, significantly greater than that of the control group (-3.57 ± 1.49 D, p < 0.001). Axial length (AL) changes were -0.06 ± 0.19 mm and 0.26 ± 0.15 mm in the LLRT group and control group (p < 0.001), respectively. The subfoveal choroidal thickness changed by 45.32 ± 30.88 μm for children treated with LLRT at the 9-month examination (p < 0.001). Specifically, a substantial hyperopic shift (0.31 ± 0.24 D and 0.20 ± 0.14 D, respectively, p = 0.02) was found in the 8-14 year olds compared with 4-7 year old children. The decrease in AL in subjects with baseline AL >24 mm was -0.08 ± 0.19 mm, significantly greater than those with a baseline AL ≤24 mm (-0.04 ± 0.18 mm, p = 0.03).

CONCLUSIONS

Repetitive exposure to LLRT therapy was associated with slower myopia progression and reduced axial growth after short durations of treatment. These results require further validation in randomised controlled trials.

Update and guidance on management of myopia. European Society of Ophthalmology in cooperation with International Myopia Institute

The prevalence of myopia is increasing extensively worldwide. The number of people with myopia in 2020 is predicted to be 2.6 billion globally, which is expected to rise up to 4.9 billion by 2050, unless preventive actions and interventions are taken. The number of individuals with high myopia is also increasing substantially and pathological myopia is predicted to become the most common cause of irreversible vision impairment and blindness worldwide and also in Europe. These prevalence estimates indicate the importance of reducing the burden of myopia by means of myopia control interventions to prevent myopia onset and to slow down myopia progression. Due to the urgency of the situation, the European Society of Ophthalmology decided to publish this update of the current information and guidance on management of myopia. The pathogenesis and genetics of myopia are also summarized and epidemiology, risk factors, preventive and treatment options are discussed in details.

Visual Performance with Spherical and Multifocal Contact Lenses in a Pediatric Population

SIGNIFICANCE

This pilot study compared subjective and objective vision of children wearing single-vision and +2.00, +3.00, and +4.00 D add power soft multifocal contact lenses to determine whether the higher add power-thought to provide better myopia control-resulted in visual compromise.

PURPOSE

This study aimed to determine the maximum add power children wearing center-distance soft multifocal contact lenses could accept objectively and subjectively.

METHODS

Myopic children were assigned in random order to wear omafilcon A single-vision or multifocal "D" contact lenses with +2.00, +3.00, or +4.00 D add power for 1 week each. High-contrast distance and near visual acuity, low-contrast distance visual acuity, and contrast sensitivity were measured at each visit along with a quality of vision questionnaire to assess their vision. The Friedman test was performed to evaluate the impact of add power on all outcome measures.

RESULTS

Eleven subjects were enrolled, and nine subjects completed the study. The median age of completed subjects was 11 years. Median logMAR low-contrast distance visual acuity was reduced in the +3.00 (+0.20) and +4.00 (+0.28) D add lenses compared with the +2.00 (+0.16) D add and single-vision lenses (+0.10, P < .001). All three multifocal lenses resulted in reduced contrast sensitivity (+1.35 to +1.40) compared with single-vision lenses (+1.60, P < .001). In general, +3.00 and +4.00 D add lenses resulted in worse glare/starbursts, ghost images, computer vision, changing fixation distance, and overall vision, but results varied. There were no differences among the lenses with respect to subjective assessments of distance vision, near vision, strain or tiredness, contact lens comfort, or sporting activities.

CONCLUSIONS

The +3.00 D and higher add powers result in more objective and subjective vision-related issues than single-vision lenses, but the +2.00 D add multifocal lenses were well tolerated.

Mandated Kindergarten Eye Examinations in a US Suburban Clinic: Is It Worth the Cost?

Purpose

The state of Illinois has required an examination by an optometrist or ophthalmologist prior to mandatory kindergarten since 2008. This requirement has allowed us to gather information regarding disease prevalence in a local suburban population.

Methods

A retrospective chart review was undertaken of kindergarten eye examinations performed at the Wheaton Eye Clinic between September 2008 and February 2017. Inclusion criteria included school eye examination as a reason for the visit, and a cycloplegic refraction was completed.

Results

Of 3612 patient charts identified, 1085 satisfied the inclusion criteria, of which 48% were female. The average age of the patients was 5.3 years (range, 3.8 to 6.7). Historical characteristics showed 143 (13%) were premature, 28 (3%) patients were autistic and 109 (10%) were developmentally delayed. On examination, 56 (5%) had <20/40 (WHO mild visual impairment) vision in better seeing eye, 34 (3%) had spherical equivalent refractive error in either eye > +3.50 diopters and one < −3.00 diopters. Fifty-eight patients (5%) were diagnosed with amblyopia and 101 patients (9.3%) were given glasses. Abnormal external exam finding was found in 218 (20%) while 16 (1.5%) had an abnormal fundus finding. Thirteen percent (146/1085) had a clinically relevant diagnosis in our examinations, with a cost of $1635/diagnosis. In total, our follow-up rate was 83% (78/94).

Conclusion

Our rate of treatable ocular conditions discovered via state-mandated kindergarten eye examinations is similar to large-scale screening programs. The cost per condition found with full examinations was substantially higher; however, follow-up was more consistent.

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Hydrogen Peroxide Disinfecting Solution for Gas Permeable Contact Lenses: A Review of the Antimicrobial Efficacy, Compatibility, and Safety Performance of a One-Step Lens Care System

CLEAR CARE PLUS (CCP), also known as AOSEPT PLUS with HydraGlyde, is approved for use with gas permeable (GP) lenses, and the indication is supported by the scientific evidence that is reviewed in this article. Antimicrobial efficacy testing of CCP both as a stand-alone disinfectant and as part of a regimen shows that CCP exceeds the ISO 14729 criteria against bacteria, yeast, and mold. In real-world conditions, it is effective against clinically relevant bacterial strains isolated from adverse events and against the two forms, trophozoites and cysts, of resilient Acanthamoeba species. Compatibility tests of CCP with two types of GP lenses indicate that the physical and/or optical parameters of lenses are unaffected through 30 cycles of simulated use with CCP, and a clinical trial shows substantial equivalence of clinical performance with a commonly used GP multipurpose solution. These results indicate that CCP is well suited for cleaning and disinfection of GP contact lenses.

A machine learning-based algorithm used to estimate the physiological elongation of ocular axial length in myopic children

Background

Axial myopia is the most common type of myopia. However, due to the high incidence of myopia in Chinese children, few studies estimating the physiological elongation of the ocular axial length (AL), which does not cause myopia progression and differs from the non-physiological elongation of AL, have been conducted. The purpose of our study was to construct a machine learning (ML)-based model for estimating the physiological elongation of AL in a sample of Chinese school-aged myopic children.

Methods

In total, 1011 myopic children aged 6 to 18 years participated in this study. Cross-sectional datasets were used to optimize the ML algorithms. The input variables included age, sex, central corneal thickness (CCT), spherical equivalent refractive error (SER), mean K reading (K-mean), and white-to-white corneal diameter (WTW). The output variable was AL. A 5-fold cross-validation scheme was used to randomly divide all data into 5 groups, including 4 groups used as training data and one group used as validation data. Six types of ML algorithms were implemented in our models. The best-performing algorithm was applied to predict AL, and estimates of the physiological elongation of AL were obtained as the partial derivatives of AL_predicted-age curves based on an unchanged SER value with increasing age.

Results

Among the six algorithms, the robust linear regression model was the best model for predicting AL, with a R² value of 0.87 and relatively minimal averaged errors between the predicted AL and true AL. Based on the partial derivatives of the AL_predicted-age curves, the estimated physiological AL elongation varied from 0.010 to 0.116 mm/year in male subjects and 0.003 to 0.110 mm/year in female subjects and was influenced by age, SER and K-mean. According to the model, the physiological elongation of AL linearly decreased with increasing age and was negatively correlated with the SER and the K-mean.

Conclusions

The physiological elongation of the AL is rarely recorded in clinical data in China. In cases of unavailable clinical data, an ML algorithm could provide practitioners a reasonable model that can be used to estimate the physiological elongation of AL, which is especially useful when monitoring myopia progression in orthokeratology lens wearers.

Topical bendazol inhibits experimental myopia progression and decreases the ocular accumulation of HIF-1α protein in young rabbits

PURPOSE

To investigate the inhibitory effect of bendazol on form-deprivation myopia (FDM) in rabbits as well as the underlying biochemical processes.

METHODS

Forty-eight 3-week-old New Zealand white rabbits were randomly assigned to three groups: a control group, a form-deprivation (FD) group and an FD + bendazol group (treated with 1% bendazol in the FD eyes). Refraction, corneal curvature, vitreous chamber depth (VCD) and axial length (AL) were assessed using streak retinoscopy, keratometry, and A-scan ultrasonography, respectively. Eyeballs were enucleated for histological analysis, and ocular tissues were homogenized to determine the mRNA and protein expression of hypoxia-inducible factor-1α (HIF-1α) and muscarinic acetylcholine receptors (mAChRs).

RESULTS

Bendazol inhibited the progression of FDM and suppressed the upregulation of HIF-1α. At week 6, in the control, FD and FD + bendazol groups, the refraction values were 1.38 ± 0.43, 0.03 ± 0.47 and 1.25 ± 0.35 D, respectively (p < 0.001); the ALs were 13.91 ± 0.11, 14.15 ± 0.06 and 13.97 ± 0.10 mm, respectively (p < 0.001) and the VCDs were 6.56 ± 0.06, 6.69 ± 0.07 and 6.61 ± 0.06 mm, respectively (p < 0.001). HIF-1α was upregulated in FD eyes but downregulated in FD + bendazol eyes, while the mAChRs were the opposite.

CONCLUSIONS

In the FD rabbit model, bendazol significantly inhibits the development of myopia and downregulates HIF-1α expression, which may provide a novel therapeutic approach for myopia control.

Changes in axial length after orthokeratology lens treatment for myopia: a meta-analysis

PURPOSE

Orthokeratology (OK) lens is a popular optical method to control myopia progression. This study aimed to assess the effect of OK lens on axial length change compared with glasses.

METHODS

PubMed, Web of Science, and Embase were searched to retrieve the related articles. Then, the articles were selected according to predefined criteria. Standardized mean difference (SMD) and 95% confidence interval (CI) were selected as effect size for combining and analyzing the change in axial length.

RESULTS

A total of 13 articles were included in the present study. Different models were selected according to the heterogeneity of each analysis. The axial length change in OKs group was significantly smaller than control group; SMD (95% CI) of change in axial length was - 0.857 (- 1.146, - 0.568), p < 0.001 at the end of 1 year and - 0.701 (- 1.675, 0.272), p < 0.001 at the end of 2 years or longer time.

CONCLUSIONS

OK lens treatment appears more effective in slowing axial elongation than glasses during the early treatment of myopia in children.

IMI - Myopia Control Reports Overview and Introduction

With the growing prevalence of myopia, already at epidemic levels in some countries, there is an urgent need for new management approaches. However, with the increasing number of research publications on the topic of myopia control, there is also a clear necessity for agreement and guidance on key issues, including on how myopia should be defined and how interventions, validated by well-conducted clinical trials, should be appropriately and ethically applied. The International Myopia Institute (IMI) reports the critical review and synthesis of the research evidence to date, from animal models, genetics, clinical studies, and randomized controlled trials, by more than 85 multidisciplinary experts in the field, as the basis for the recommendations contained therein. As background to the need for myopia control, the risk factors for myopia onset and progression are reviewed. The seven generated reports are summarized: (1) Defining and Classifying Myopia, (2) Experimental Models of Emmetropization and Myopia, (3) Myopia Genetics, (4) Interventions for Myopia Onset and Progression, (5) Clinical Myopia Control Trials and Instrumentation, (6) Industry Guidelines and Ethical Considerations for Myopia Control, and (7) Clinical Myopia Management Guidelines.

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.

Unilateral Refractive Surgery and Myopia Progression

PURPOSE

To compare the progression of myopia in eyes that underwent unilateral refractive surgery with non-operated eyes.

METHODS

Three patients who underwent refractive myopic correction in one eye are described. The collected preoperative and postoperative data included age, gender, subjective refraction, best corrected visual acuity, and uncorrected visual acuity.

RESULTS

The first patient (19-year-old woman) had photorefractive keratectomy in her left eye and the myopic progression was 1.20 diopters (D) (3 years postoperatively) compared to -2.50 D in her non-operated eye. The second patient (30-year-old man) had laser-assisted in situ keratomileusis in his left eye with a myopic progression of 0.25 D compared to 0.75 D in his non-operated eye (10 years postoperatively). The third patient (22-year-old man) underwent photorefractive keratectomy in his right eye with no myopic progression compared to -1.50 D in his non-operated eye (3 years postoperatively).

CONCLUSIONS

These three cases suggest that refractive surgery for myopia correction may be associated with a slower progression of myopia postoperatively. [J Pediatr Ophthalmol Strabismus. 2019;56(2):78-82.].

The Role of Bottom-Up and Top-Down Cortical Interactions in Adaptation to Natural Scene Statistics

Adaptation is a mechanism by which cortical neurons adjust their responses according to recently viewed stimuli. Visual information is processed in a circuit formed by feedforward (FF) and feedback (FB) synaptic connections of neurons in different cortical layers. Here, the functional role of FF-FB streams and their synaptic dynamics in adaptation to natural stimuli is assessed in psychophysics and neural model. We propose a cortical model which predicts psychophysically observed motion adaptation aftereffects (MAE) after exposure to geometrically distorted natural image sequences. The model comprises direction selective neurons in V1 and MT connected by recurrent FF and FB dynamic synapses. Psychophysically plausible model MAEs were obtained from synaptic changes within neurons tuned to salient direction signals of the broadband natural input. It is conceived that, motion disambiguation by FF-FB interactions is critical to encode this salient information. Moreover, only FF-FB dynamic synapses operating at distinct rates predicted psychophysical MAEs at different adaptation time-scales which could not be accounted for by single rate dynamic synapses in either of the streams. Recurrent FF-FB pathways thereby play a role during adaptation in a natural environment, specifically in inducing multilevel cortical plasticity to salient information and in mediating adaptation at different time-scales.

Association Between Hay Fever and High Myopia in United States Adolescents and Adults

OBJECTIVES

To investigate the relationship between hay fever and refractive error in a representative sample of adolescents and adults in the United States.

METHODS

This cross-sectional study included 5,744 participants aged ≥12 years from the 2005 to 2006 National Health and Nutrition Examination Survey who participated in the allergy questionnaire, completed objective refraction and keratometry in both eyes, and had immunoglobulin E (IgE) serology. The primary predictor variable, refractive error, was classified as emmetropia (-0.99 to +0.99 diopters [D]), low myopia (-1.00 to -2.99 D), moderate myopia (-3.00 to -5.99 D), high myopia (≥-6.00 D), or hyperopia (≥1.00 D). Covariates included age, gender, race, asthma, eczema, total serum IgE ≥120 kU/L, corneal steepness, and corneal astigmatism. The primary outcome was hay fever.

RESULTS

The study population's mean age was 41.7 years; 48.8% of subjects were men and 51.2% were women. The prevalence of hay fever was 12.1% overall. High myopes had 2.7 times higher odds of hay fever compared to emmetropes (OR 2.67, CI, 1.57-4.51, P=0.001), which was independent of demographics, atopic conditions, IgE serology, and keratometry measurements.

CONCLUSIONS

The association between hay fever and high myopia identified in this large cross-sectional study remains speculative and was not mediated through corneal steepness or corneal astigmatism. Further prospective studies may help elucidate the directionality of the association between hay fever and high myopia.

Interventions to control myopia progression in children: protocol for an overview of systematic reviews and meta-analyses

BACKGROUND

Myopia is a common visual disorder with increasing prevalence among developed countries of the world. Myopia constitutes a substantial risk factor for several ocular conditions that can lead to blindness. The purpose of this study is to conduct an overview of systematic reviews and meta-analyses in order to identify and appraise robust research evidence regarding the management of myopia progression in children and adolescents.

METHODS

A literature search will be conducted in MEDLINE, EMBASE, The Cochrane Database of Systematic Reviews (CDSR), Database of Abstracts of Reviews of Effects (DARE), and Health Technology Assessment (HTA) Database via Centre for Reviews and Dissemination (CRD). We will search for systematic reviews or meta-analyses that examine optical or pharmaceutical modalities for myopia control. Two independent overview authors will screen the titles and abstracts against the eligibility criteria. Individual study's methodological quality and quality of evidence for each outcome of interest will be assessed by two independent authors using the ROBIS tool and GRADE rating, respectively. In cases of disagreement, consensus will be reached with the help of a third author. Our primary outcomes will be the mean change in refractive error, mean axial length change, and adverse events. A citation matrix will be generated, and the corrected covered area (CCA) will be estimated, in order to identify overlapping primary studies. Possible meta-biases and measures of heterogeneity will be described, and cases of dual co-authorship will be identified and discussed. If any recently published randomized controlled trials (RCTs) are detected, these will be appraised and their findings will be presented. An overall summary of outcomes will be provided using descriptive statistics and will be supplemented by narrative synthesis.

DISCUSSION

This overview will examine the high level of existing evidence for treatment of myopia progression. Efficient interventions will be identified, and side effects will be reported. The expected benefit is that all robust recent research evidence will be compiled in a single study. The results may inform future research in this area, which should provide insight into the appropriate regimes for the administration of these modalities and contribute to future guideline development.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO CRD42017068204.

The increasing prevalence of myopia in junior high school students in the Haidian District of Beijing, China: a 10-year population-based survey

Background

Myopia is a leading cause of preventable blindness. Although, multiple cross-sectional epidemiological studies have confirmed that there is a high prevalence of myopia in high school-aged students in China. However, few longitudinal studies have been performed to assess junior high school students. In the present study, we investigate changes in the prevalence of myopia in third year junior high school (grade 9) students in the Haidian District of Beijing, China, from 2006 to 2015.

Methods

A retrospective, longitudinal cohort study was performed over 10 years. A total of 37,424 third-year middle school (grade 9) students from 8 junior high schools in Haidian district, Beijing, were included. Participants underwent a comprehensive ophthalmic examination in which they were evaluated using autorefraction under cycloplegia and submitted to retinoscopy to assess accuracy. According to the spherical equivalent refraction (SER) of the right eye, subjects were separated into the following groups: non-myopia, −0.5 ≤ SER diopters (D); low myopia, −3.0 ≤ SER < −0.5 D; moderate myopia, −6.0 ≤ SER < −3.0 D; and high myopia, SER > −6.0 D. The following characteristics were measured: refractive error; the proportion of subjects with non- myopia, low myopia, moderate myopia and high myopia; and the difference in the prevalence of myopia between male and female subjects.

Results

From 2006 to 2015, the prevalence of non-myopia (from 44.05% to 34.52%) and low myopia (from 32.27% to 20.73%) decreased, while the prevalence of moderate myopia (from 19.72% to 38.06%) and high myopia (from 3.96% to 6.69%) significantly increased. For refractive error, the worse eye was −2.23 ± 2.42 D (median, −1.75; range − 12.75 to +8.50) in 2006 and −3.13 ± 2.66 D (median, −2.75; range − 12.75 to +8.50) in 2015. When the entire population was considered, the overall prevalence of myopia increased from 55.95% in 2005 to 65.48% in 2015. There was a significant positive relationship between the year and the prevalence of myopia in both girls and boys. Girls were more likely than boys to have myopia (odds ratio, 1.43 [95% CI, 1.14–1.96]), especially moderate myopia, and the prevalence of moderate and high myopia were higher in girls than in boys.

Conclusions

During the last 10 years, the prevalence of myopia significantly increased on an annual basis among third-year junior high school students in the Haidian District of Beijing, China. The total prevalence of myopia was significantly higher in girl than in boy participants. The refractive status of this age group deserves particular attention.

Electronic supplementary material

The online version of this article (doi:10.1186/s12886-017-0483-6) contains supplementary material, which is available to authorized users.

Update on Orthokeratology in Managing Progressive Myopia in Children: Efficacy, Mechanisms, and Concerns

Myopia is an important public health issue, and high myopia may lead to severe complications if left untreated. Orthokeratology lenses, worn overnight to reshape the cornea, are one of many recent modalities used to slow down the progression of myopia in children. This treatment has been proven successful, as evidenced by decreased spherical refractive error and axial length relative to the control at interval follow-up ranging from 6 months to 5 years. In this systematic review, the authors collected published controlled studies that analyzed the efficacy of orthokeratology lens wear and calculated longitudinal relative changes in axial length, revealing a weighted average of -45.1% change in axial length at the 2-year follow-up. The exact mechanism by which orthokeratology lenses reduce myopia progression is unknown, but research shows that the corneal reshaping decreases peripheral hyperopic defocus and therefore increases peripheral myopic defocus to likely reduce stimuli for axial elongation and subsequent development of myopia. Use of orthokeratology lenses is generally safe, but cases of associated infectious keratitis may have a higher incidence of virulent organisms such as Pseudomonas, Acanthamoeba, and antibacterial-resistant strains of Staphylococcus, partially due to the required overnight use of these lenses. Orthokeratology is regarded as one of the most effective non-pharmacologic measures to slow progression of myopia in children and, with regular follow-up to ensure safety, continues to be one of the most effective treatments for myopia management around the world. [J Pediatr Ophthalmol Strabismus. 2017;54(3):142-148.].

Factors related to axial length elongation and myopia progression in orthokeratology practice

Purpose

To investigate which baseline factors are predictive for axial length growth over an average period of 2.5 years in a group of children wearing orthokeratology (OK) contact lenses.

Methods

In this retrospective study, the clinical records of 249 new OK wearers between January 2012 and December 2013 from the contact lens clinic at the Eye and ENT Hospital of Fudan University were reviewed. The primary outcome measure was axial length change from baseline to the time of review (July-August 2015). Independent variables included baseline measures of age at initiation of OK wear, gender, refractive error (spherical equivalent), astigmatism, average keratometry, corneal toricity, central corneal thickness, white-to-white corneal diameter, pupil size, corneal topography eccentricity value (e-value), intraocular pressure (IOP) and total time in follow-up (months total). The contributions of all independent variables on axial length change at the time of review were assessed using univariate and multivariable regression analyses.

Results

Univariate analyses of the right eyes of 249 OK patients showed that smaller increases in axial length were associated with older age at the onset of OK lens wear, greater baseline spherical equivalent myopic refractive error, less time in follow-up and a smaller e-value. Multivariable analyses of the significant right eye variables showed that the factors associated with smaller axial length growth were older age at the onset of OK lens wear (p<0.0001), greater baseline spherical equivalent myopic refractive error (p = 0.0046) and less time in follow-up (p<0.0001).

Conclusions

The baseline factors demonstrating the greatest correlation with reduced axial length elongation during OK lens wear in myopic children included greater baseline spherical equivalent myopic refractive error and older age at the onset of OK lens wear.

Myopia onset and role of peripheral refraction

BACKGROUND

To determine the peripheral refraction characteristics related to 18-month changes in refraction in Caucasian (Mediterranean) children.

METHODS

Non-cycloplegic peripheral refraction at 10° intervals over the central ±30° of horizontal visual field over 18 months (baseline, 12 months, and 18 months of follow-up) was conducted in 50 healthy children who were 8 years old. Axial length (AL) was also recorded. Relative peripheral refraction (RPR) was calculated and eyes were divided into three study groups: non-myopic eyes, myopic eyes, and eyes that develop myopia.

RESULTS

Myopic eyes showed hyperopic RPR and emetropic and hyperopic eyes showed myopic RPR. Univariate analysis of variance did not find any statistically significant effect of peripheral refraction (F₃₆=0.13; P=1.00) and RPR (F₃₆=0.79; P=0.80) on myopia onset (eyes that developed myopia along the study). All the studied groups showed an increase of AL, without statistically significant differences between the studied groups (F₆=0.09; P=0.99).

CONCLUSION

Hyperopic relative peripheral shift change in eyes that develop myopia has been found with differences in RPR between myopic (hyperopic RPR) and hyperopic or emmetropic eyes (with myopic RPR). The results suggest that RPR cannot predict development or progression of myopia in Caucasian (Mediterranean) children and the efficacy in slowing myopia progression obtained with treatments that manipulate the peripheral refraction is not just driven with RPR.

Expert Views on Innovative Future Uses for Contact Lenses

Over the past 10 to 15 years, the availability of new materials and technologies has resulted in revolutionary concepts for contact lenses being proposed that go well beyond correcting vision. These novel uses include their prescribing to deliver topical ocular and systemic drugs, assist with ocular surface disease management, and limit the progression of myopia and novel methods to display visual information. How likely are these concepts to become commercially available, how successful will they be, and what are the potential issues to consider for them to come to market? To answer these questions, a panel of four experts were invited to discuss the benefits and pitfalls of these technologies and what challenges lay ahead of these concepts before their availability. Their responses provide a fascinating insight for the clinician into the likelihood of such revolutionary contact lenses being available in a clinical setting.

RPE and Choroid Mechanisms Underlying Ocular Growth and Myopia

Myopia is the most common type of refractive errors and one of the world's leading causes of blindness. Visual manipulations in animal models have provided convincing evidence for the role of environmental factors in myopia development. These models along with in vitro studies have provided important insights into underlying mechanisms. The key locations of the retinal pigment epithelium (RPE) and choroid make them plausible conduits for relaying growth regulatory signals originating in the retina to the sclera, which ultimately determines eye size and shape. Identifying the key signal molecules and their targets may lead to the development of new myopia control treatments. This section summarizes findings implicating the RPE and choroid in myopia development. For RPE and/or choroid, changes in morphology, activity of ion channels/transporters, as well as in gene and protein expression, have been linked to altered eye growth. Both tissues thus represent potential targets for novel therapies for myopia.