Atropine for the treatment of childhood myopia. An intervention trial on efficacy of atropine and multi-focal glasses in controlling myopic progression. A randomized trial of the effects of rigid contact lenses on myopia progression. Can bifocals slow myopia progression? Effect of progressive addition lenses on myopia progression in Japanese children: a prospective, randomized, double-masked, crossover trial. A randomized clinical trial of bifocal glasses for myopic children with esophoria: results after 54 months. A randomized clinical trial of progressive addition lenses versus single vision lenses on the progression of myopia in children. Effects of different concentrations of atropine on controlling myopia in myopic children. The effectiveness of progressive addition lenses on the progression of myopia in Chinese children. Comparison of the effect of atropine and cyclopentolate on myopia. Houston Myopia Control Study: a randomized clinical trial. Part II. Final report by the patient care team. Randomized trial of effect of bifocal and prismatic bifocal spectacles on myopic progression: two-year results. A combined therapy using stimulating auricular acupoints enhances lower-level atropine eyedrops when used for myopia control in school-aged children evaluated by a pilot randomized controlled clinical trial. The Hong Kong progressive lens myopia control study: study design and main findings. One-year multicenter, double-masked, placebo-controlled, parallel safety and efficacy study of 2% pirenzepine ophthalmic gel in children with myopia. Effect of spectacle use and accommodation on myopic progression: final results of a three-year randomised clinical trial among schoolchildren. Undercorrection of myopia enhances rather than inhibits myopia progression. A pilot randomized controlled study on the effect of laser photocoagulation of confluent soft macular drusen. Spectacle lenses designed to reduce progression of myopia: 12-month results. The possible effect of undercorrection on myopic progression in children.
To evaluate the efficacy and safety of topical atropine, a nonselective muscarinic antagonist, in slowing the progression of myopia and ocular axial elongation in Asian children.
                Parallel-group, placebo-controlled, randomized, double-masked study.
                Four hundred children aged 6 to 12 years with refractive error of spherical equivalent -1.00 to -6.00 diopters (D) and astigmatism of -1.50 D or less.
                Participants were assigned with equal probability to receive either 1% atropine or vehicle eye drops once nightly for 2 years. Only 1 eye of each subject was chosen through randomization for treatment.
                The main efficacy outcome measures were change in spherical equivalent refraction as measured by cycloplegic autorefraction and change in ocular axial length as measured by ultrasonography. The primary safety outcome measure was the occurrence of adverse events.
                Three hundred forty-six (86.5%) children completed the 2-year study. After 2 years, the mean progression of myopia and of axial elongation in the placebo-treated control eyes was -1.20+/-0.69 D and 0.38+/-0.38 mm, respectively. In the atropine-treated eyes, myopia progression was only -0.28+/-0.92 D, whereas the axial length remained essentially unchanged compared with baseline (-0.02+/-0.35 mm). The differences in myopia progression and axial elongation between the 2 groups were -0.92 D (95% confidence interval, -1.10 to -0.77 D; P<0.001) and 0.40 mm (95% confidence interval, 0.35-0.45 mm; P<0.001), respectively. No serious adverse events related to atropine were reported.
                Topical atropine was well tolerated and effective in slowing the progression of low and moderate myopia and ocular axial elongation in Asian children. This randomized clinical trial assessed the treatment effects of atropine and/or multi-focal lenses in decreasing the progression rate of myopia in children.
                Two hundred and twenty-seven schoolchildren with myopia, aged from 6 to 13 years, who were stratified based on gender, age and the initial amount of myopia were randomly assigned to three treatment groups: 0.5% atropine with multi-focal glasses, multi-focal glasses, and single vision spectacles. Each subject was followed for at least eighteen months. These results report on the 188 patients available for the follow-up.
                The mean progression of myopia in atropine with multi-focal glasses group (0.41 D) was significantly less than the multi-focal (1.19 D) and single vision group (1.40 D) (p < 0.0001). But no significant difference was noted between the last two groups (p = 0.44). The progression of myopia was significantly correlated with the increases of axial length (r = 0.65, p = 0.0001), but not with the changes of corneal power (r=-0.09), anterior chamber depth (r = -0.023), lens thickness (r = -0.08), or intra-ocular pressure (r = -0.008).
                The 0.5% atropine with multi-focal lenses can slow down the progression rate of myopia. However, multi-focal lenses alone showed no difference in effect compared to control. To compare the effects of rigid gas-permeable contact lenses (RGPs) and soft contact lenses (SCLs) on myopia progression in children.
                We randomly assigned 116 subjects to wear RGPs or SCLs. Subjects underwent cycloplegic autorefraction, keratometry, and A-scan ultrasonographic axial length measurements at each annual visit. All analyses were conducted according to the original randomization assignment. The primary outcome measure was the 3-year change in spherical equivalent cycloplegic autorefraction.
                The mean +/- SD spherical equivalent cycloplegic refractive error progressed -1.56 +/- 0.95 diopters (D) for RGP wearers and -2.19 +/- 0.89 D for the SCL wearers during the 3 years of the study (analysis of covariance [ANCOVA], P<.001). The axial growth of the eyes was not significantly different between treatment groups (ANCOVA, P = .57). The steep corneal meridian of the RGP wearers steepened 0.62 +/- 0.60 D, and that of the SCL wearers steepened 0.88 +/- 0.57 D during the 3 years (ANCOVA, P = .01).
                The RGP wearers' myopia progressed less than that of the SCL wearers. The corneal curvature of the SCL wearers steepened more than that of the RGP wearers, but the axial growth was not significantly different between the groups. Most refractive error treatment effect was limited to the first year of the trial. The results of the study provide information for eye care practitioners to share with their patients, but they do not indicate that RGPs should be prescribed primarily for myopia control. Retrospective studies have suggested that in children with near point esophoria, bifocals can slow myopia progression by about 50 percent. A prospective study was conducted to test this hypothesis.
                Thirty-two children, all with near point esophoria, were randomly divided into either correction with single-vision or with bifocal lenses containing a +1.25 D and. Axial length and refraction were measured under cycloplegia every 6 months for 18 months. Twenty-eight children completed the study.
                Myopia progressed at an equal rate in both groups for the first 12 months. Progression was much faster during the first 6 months, which was during the school year, than during the second 6 months, which included all of the summer vacation (0.64 D/yr vs 0.29 D/yr). During the last 6 months, myopia progressed rapidly for children in single-vision lenses (0.80 D/yr) but slowly for those in bifocals (0.37 D/yr). A repeated-measure analysis of variance showed that season of the year had a significant effect on myopia progression (p > 0.002) and that the effect differed for the two treatment groups (p > 0.043). Over the whole 18-month study, myopia progressed at rate of 0.57 D/yr for those in single-vision lenses and 0.39 D/yr in those in bifocals (p = 0.26).
                Bifocals seemed to slow myopia progression in these children with near-point esophoria, although a longer-term study with more subjects is needed to confirm this finding. Myopia progressed more rapidly during the school year than during summer vacation. This prospective, randomized, double-masked, crossover trial was conducted to evaluate the clinical effectiveness of progressive addition lenses (PALs) compared with single-vision lenses (SVLs) on myopia progression in Japanese children.
                Ninety-two children fulfilling the inclusion criteria (age: 6-12 years, spherical equivalent refractive errors: -1.25 to -6.00 D) were randomly allocated to either 18 months of wearing PALs (near addition: +1.50 D) followed by 18 months of SVLs (group 1), or 18 months of wearing SVLs followed by 18 months of wearing PALs (group 2), and were followed up for 3 years (two-stage crossover design). The primary outcome measure was myopia progression, as determined by cycloplegic autorefraction.
                Eighty-six (93%) children completed both treatment periods. A mixed-model, two-way analysis of variance (ANOVA) performed using 3-year data identified a significant treatment effect of PALs compared with SVLs (P = 0.0007), with a mean 18-month difference of 0.17 D (95% CI: 0.07-0.26 D). This analysis also indicated a significant period effect (P = 0.0040) and a significant treatment-by-period interaction (P = 0.0223): Group 1 showed a slower myopia progression than did group 2.
                The use of PALs slowed myopia progression, although the treatment effect was small, as previously reported in ethnically diverse children in the United States. The significant treatment-by-period interaction suggests that early application of PALs would probably be more beneficial for these age and refraction ranges (isrctn.org number, 28611140). We previously reported results of a randomized clinical trial of bifocals as a type of myopia correction for children with near-point esophoria. After 30 months, the rate of myopia progression in 36 children wearing bifocals averaged 0.40 D/yr compared to 0.50 D/yr in 39 children wearing single-vision glasses (p= 0.046, age-adjusted). Here we report on the 46 children in that study who completed 54 months of followup.
                For each treatment group, we examined the pattern of change in myopia over the first and second halves of the 54-month period to see if the beneficial effect of wearing bifocals was present initially for those 46 children, as it was in the entire group, and to see if the myopia-slowing effect continued to accumulate during the second part of the study. During the last 12 months of the 54-month period, subjects were free to select any mode of myopic treatment, but this intent-to-treat analysis classified all children according to their original treatment assignment.
                During the first 24 months, the pattern of change in myopia differed between the two groups (p = 0.041), with those in bifocals showing slower progression. A similar trend was observed for vitreous chamber growth (p= 0.059). During the last 30 months, myopia progressed at a similar rate for both groups, including during the last year, when many subjects changed their mode of myopia correction.
                Wearing bifocals instead of single-vision glasses caused a slowing of myopia progression evident during the first two years. During the subsequent two-and-a-half years of followup, the difference in the degree of myopia was maintained, but did not increase. The purpose of the Correction of Myopia Evaluation Trial (COMET) was to evaluate the effect of progressive addition lenses (PALs) compared with single vision lenses (SVLs) on the progression of juvenile-onset myopia.
                COMET enrolled 469 children (ages 6-11 years) with myopia between -1.25 and -4.50 D spherical equivalent. The children were recruited at four colleges of optometry in the United States and were ethnically diverse. They were randomly assigned to receive either PALs with a +2.00 addition (n = 235) or SVLs (n = 234), the conventional spectacle treatment for myopia, and were followed for 3 years. The primary outcome measure was progression of myopia, as determined by autorefraction after cycloplegia with 2 drops of 1% tropicamide at each annual visit. The secondary outcome measure was change in axial length of the eyes, as assessed by A-scan ultrasonography. Child-based analyses (i.e., the mean of the two eyes) were used. Results were adjusted for important covariates, by using multiple linear regression.
                Of the 469 children (mean age at baseline, 9.3 +/- 1.3 years), 462 (98.5%) completed the 3-year visit. Mean (+/-SE) 3-year increases in myopia (spherical equivalent) were -1.28 +/- 0.06 D in the PAL group and -1.48 +/- 0.06 D in the SVL group. The 3-year difference in progression of 0.20 +/- 0.08 D between the two groups was statistically significant (P = 0.004). The treatment effect was observed primarily in the first year. The number of prescription changes differed significantly by treatment group only in the first year. At 6 months, 17% of the PAL group versus 30% of the SVL group needed a prescription change (P = 0.0007), and, at 1 year, 43% of the PAL group versus 59% of the SVL group required a prescription change (P = 0.002). Interaction analyses identified a significantly larger treatment effect of PALs in children with lower versus higher baseline accommodative response at near (P = 0.03) and with lower versus higher baseline myopia (P = 0.04). Mean (+/- SE) increases in the axial length of eyes of children in the PAL and SVL groups, respectively, were: 0.64 +/- 0.02 mm and 0.75 +/- 0.02 mm, with a statistically significant 3-year mean difference of 0.11 +/- 0.03 mm (P = 0.0002). Mean changes in axial length correlated with those in refractive error (r = 0.86 for PAL and 0.89 for SVL).
                Use of PALs compared with SVLs slowed the progression of myopia in COMET children by a small, statistically significant amount only during the first year. The size of the treatment effect remained similar and significant for the next 2 years. The results provide some support for the COMET rationale-that is, a role for defocus in progression of myopia. The small magnitude of the effect does not warrant a change in clinical practice. Although 1% atropine effectively slows myopia progression, it is associated with adverse effects, including photophobia, blurred near vision, and poor compliance. We investigated whether lower doses of atropine would control myopia progression. One hundred and eighty-six children, from 6 to 13 years of age, were treated each night with different concentrations of atropine eye drops or a control treatment for up to 2 years. The mean myopic progression in each of the groups was 0.04 +/-0.63 diopter per year (D/Y) in the 0.5% atropine group, 0.45+/-0.55 D/Y in the 0.25% atropine group, and 0.47+/-0.91 D/Y in the 0.1% atropine group. All atropine groups showed significantly less myopic progression than the control group (1.06+/-0.61 D/Y) (p<0.01). Our study also showed that 61% of students in the 0.5% atropine group, 49% in the 0.25% atropine group and 42% in the 0.1% atropine group had no myopic progression. However, 4% of children in the 0.5% atropine group, 17% in the 0.25% atropine group, and 33% in the 0.1% atropine group still had fast myopic progression (>-1.0 D/Y). In contrast, only 8% of the control group showed no myopic progression and 44% had fast myopic progression. These results suggest that all three concentrations of atropine had significant effects on controlling myopia; however, treatment with 0.5% atropine was the most effective. To evaluate the effectiveness of progressive addition lenses (PALs), with a near addition of +1.50 D, on the progression of myopia in Chinese children.
                We enrolled 178 Chinese juvenile-onset acquired myopes (aged 7-13 years, -0.50 to -3.00 D spherical refractive error), who did not have moderately or highly myopic parents, for a 2-year prospective study. They were randomly assigned to the PAL group or single vision (SV) group. Primary measurements, which included myopia progression and ocular biometry, were performed every 6 months. Treatment effect was adjusted for important covariates, by using a multiple linear regression model.
                One hundred and forty-nine subjects (75 in SV and 74 in PAL) completed the 2-year study. The myopia progression (mean +/- S.D.) in the SV and PAL groups was -1.50 +/- 0.67 and -1.24 +/- 0.56 D, respectively. This difference of 0.26 D over 2 years was statistically significant (p = 0.01). The lens type (p = 0.02) and baseline spherical equivalent refraction (p = 0.05) were significant contributing factors to myopia progression. Mean increase in the depth of vitreous chamber was 0.70 +/- 0.40 and 0.59 +/- 0.24 mm, respectively. This difference of 0.11 mm was statistically significant (p = 0.04). Age (p < 0.01) was the only contributing factor to the elongation of vitreous chamber. Different near phoria (p < 0.01) and gender (p = 0.02) caused different treatment effects when wearing SV lenses. However, there were no factors found to influence the treatment effect of wearing PALs.
                Compared with SV lenses, myopia progression was found to be retarded by PALs to some extent in Chinese children without moderately or highly myopic parents, especially for subjects with near esophoria or females. We evaluated the effectiveness of cycloplegics in the treatment of myopia. Patients were selected randomly and divided into three groups: Group 1 received atropine 1% eye drops every other night; Group 2 received cyclopentolate 1% eye drops every night; and Group 3 received normal saline eye drops every night. All the patients were rechecked every three months. The results were evaluated at the end of one year. Ninety-six patients were evaluated, 32 in each group. The mean myopic progression was -0.219 D in the atropine group, -0.578D in the cyclopentolate group, and -0.914D in the saline group. Analysis showed that atropine and cyclopentolate are effective in slowing the progression of myopia. The effect of atropine is better than that of cyclopentolate. In a randomized clinical trial designed to test the efficacy of bifocal lenses for the control of juvenile myopia, each of 207 children between the ages of 6 and 15 years wore single vision lenses, +1.00 D add bifocals, or +2.00 D add bifocals for a period of 3 years. For the 124 subjects who completed the study, the mean changes in refraction were found to be -0.34 D per year for subjects wearing single vision lenses, -0.36 D per year for those wearing +1.00 D add bifocals, and -0.34 D per year for those wearing +2.00 D add bifocals. These differences were not statistically significant. When subjects in all three treatment groups were combined, it was found that the rate of progression tended to be the most rapid for subjects who entered the study at an early age with a large amount of myopia, and tended to be the least rapid for subjects who entered the study at a later age with a small amount of myopia. It was also found that subjects having with-the-rule astigmatism progressed more slowly than those having no astigmatism or against-the-rule astigmatism. To determine whether bifocal and prismatic bifocal spectacles could control myopia in children with high rates of myopic progression.
                This was a randomized controlled clinical trial. One hundred thirty-five (73 girls and 62 boys) myopic Chinese Canadian children (myopia of > or =1.00 diopters [D]) with myopic progression of at least 0.50 D in the preceding year were randomly assigned to 1 of 3 treatments: (1) single-vision lenses (n = 41), (2) +1.50-D executive bifocals (n = 48), or (3) +1.50-D executive bifocals with a 3-prism diopters base-in prism in the near segment of each lens (n = 46).
                Myopic progression measured by an automated refractor under cycloplegia and increase in axial length (secondary) measured by ultrasonography at 6-month intervals for 24 months. Only the data of the right eye were used.
                Of the 135 children (mean age, 10.29 years [SE, 0.15 years]; mean visual acuity, -3.08 D [SE, 0.10 D]), 131 (97%) completed the trial after 24 months. Myopic progression averaged -1.55 D (SE, 0.12 D) for those who wore single-vision lenses, -0.96 D (SE, 0.09 D) for those who wore bifocals, and -0.70 D (SE, 0.10 D) for those who wore prismatic bifocals. Axial length increased an average of 0.62 mm (SE, 0.04 mm), 0.41 mm (SE, 0.04 mm), and 0.41 mm (SE, 0.05 mm), respectively. The treatment effect of bifocals (0.59 D) and prismatic bifocals (0.85 D) was significant (P < .001) and both bifocal groups had less axial elongation (0.21 mm) than the single-vision lens group (P < .001).
                Bifocal lenses can moderately slow myopic progression in children with high rates of progression after 24 months. APPLICATIONS TO CLINICAL PRACTICE: Bifocal spectacles may be considered for slowing myopic progression in children with an annual progression rate of at least 0.50 D. This study was designed to compare the reduction in myopia progression in patients treated with atropine eyedrops alone with patients treated with a combined treatment of atropine and stimulation of the auricular acupoints.
                This study was a randomized single-blind clinical controlled trial. A total of 71 school-aged children with myopia, who fulfilled the eligibility criteria, were recruited. They were randomly assigned into three groups. These were 22 treated with the 0.25% atropine (0.25A) only, 23 treated with the 0.5% atropine (0.5A) only and 26 treated with 0.25% atropine together with stimulation of the auricular acupoints (0.25A+E). The differences in the post-treatment effects among these three groups were statistically assessed. The primary outcome parameter was myopia progression, which was defined as diopter change per year (D/Y) after cycloplegic refraction measurement.
                The mean myopia progression of the 0.25A group was 0.38+/-0.32 D/Y. No significant difference in mean myopia progression was found between the 0.5A (0.15+/-0.15 D/Y) and 0.25A+E (0.21+/-0.23 D/Y) groups. However, there was a markedly reduced myopia progression in the 0.25A+E group compared to the 0.25A group (p<0.05). Furthermore, there was no statistical difference among these three groups in axial length elongation (ALE) of eye during this stage of the investigation.
                This study demonstrates that there was efficacy in stimulating the auricular acupoints and this enhanced the action of 0.25% atropine as a means of myopia control. The result was an effect almost equal to that of 0.5% atropine alone. There is also a need that the ALE of the eye should be further investigated over a longer period using the combined therapy. To determine whether the use of progressive addition spectacle lenses reduced the progression of myopia, over a 2-year period, in Hong Kong children between the ages of 7 and 10.5 years.
                A clinical trial was carried out to compare the progression in myopia in a treatment group of 138 (121 retained) subjects wearing progressive lenses (PAL; add +1.50 D) and in a control group of 160 (133 retained) subjects wearing single vision lenses (SV). The research design was masked with random allocation to groups. Primary measurements outcomes were spherical equivalent refractive error and axial length (both measured using a cycloplegic agent).
                There were no statistically significant differences between the PAL and the SV groups for of any of the baseline outcome measures. After 2 years there had been statistically significant increases in myopia and axial length in both groups; however, there was no difference in the increases that occurred between the two groups.
                The research design used resulted in matched treatment and control groups. There was no evidence that progression of myopia was retarded by wearing progressive addition lenses, either in terms of refractive error or axial length. To evaluate the safety and efficacy of the relatively selective M(1)-antagonist, pirenzepine ophthalmic gel (gel), in slowing the progression of myopia in school-aged children.
                Parallel-group, placebo-controlled, randomized, double-masked study.
                Three hundred fifty-three healthy children, 6 to 12 years old, with a spherical equivalent (SE) of -0.75 to -4.00 diopters (D) and astigmatism of <or=1.00 D. Subjects underwent a baseline complete eye examination, and regular examinations over a 1-year period. The study was conducted at 7 academic centers and clinical practices in Asia.
                Subjects received 2% gel twice daily (gel/gel), 2% gel daily (evening, placebo/gel), or vehicle twice daily (placebo/placebo) in a 2:2:1 ratio, respectively, for 1 year.
                Spherical equivalent under cycloplegic refraction.
                At study entry, mean SE refraction was -2.4+/-0.9 D. At 12 months, there was a mean increase in myopia of 0.47 D, 0.70 D, and 0.84 D in the gel/gel, placebo/gel, and placebo/placebo groups, respectively (P<0.001 for gel/gel vs. placebo/placebo). Discontinued from the study for adverse events were 11% (31/282) of pirenzepine-treated subjects. Of the 15 serious adverse events reported in 12 subjects (all in the active groups), none was ophthalmic in nature, all subjects recovered, and only 1 (abdominal colic preceded by a flu) was judged possibly related to treatment.
                Gel (2% twice daily) was effective and relatively safe in slowing the progression of myopia over a 1-year treatment period. Two hundred and forty mildly myopic schoolchildren aged 9-11 years were randomly allocated to three treatment groups and the progression of myopia was followed-up for three years. The treatment groups were: (1) minus lenses with full correction for continuous use (the reference group), (2) minus lenses with full correction to be used for distant vision only, and (3) bifocal lenses with +1.75 D addition. Three-year refraction values were received from 237 children. The differences in the increases of the spherical equivalents were not statistically significant in the right eye, but in the left eye the change in the distant use group was significantly higher (-1.87 D) than in the continuous use group (-1.46 D) (p = 0.02, Student's t test). There were no differences between the groups in regard to school achievement, accidents, or satisfaction with glasses. In all three groups the more the daily close work done by the children the faster was the rate of myopic progression (right eye: r = 0.253, p = 0.0001, left eye: r = 0.267, p = 0.0001). Myopic progression did not correlate positively with accommodation, but the shorter the average reading distance of the follow-up time the faster was the myopic progression (right eye: r = 0.222, p = 0.0001, left eye: r = 0.255, p = 0.001). It seems that myopic progression is connected with much use of the eyes in reading and close work and with short reading distance but that progression cannot be reduced by diminishing accommodation with bifocals or by reading without spectacles. The effect of myopic defocus on myopia progression was assessed in a two-year prospective study on 94 myopes aged 9-14 years, randomly allocated to an undercorrected group or a fully corrected control group. The 47 experimental subjects were blurred by approximately +0.75 D (blurring VA to 6/12), while the controls were fully corrected. Undercorrection produced more rapid myopia progression and axial elongation (ANOVA, F(1,374)=14.32, p<0.01). Contrary to animal studies, myopic defocus speeds up myopia development in already myopic humans. Myopia could be caused by a failure to detect the direction of defocus rather than by a mechanism exhibiting a zero-point error. The authors determined the effect of photocoagulation of drusen on visual acuity and progression to subretinal neovascular membranes (SRNV).
                One of paired eyes was randomized to photocoagulation with other eye to control in 27 patients having symmetrical maculopathy and visual acuities, aged 46 to 81 years (mean, 69.7 years); follow-up 1 to 6 years (mean, 3.2 years).
                Final visual acuity was improved in treated eye or decreased in control eye in 12 patients, equal in 13 patients, and decreased in treated eye in 2 patients (P < 0.006). Progression to SRNV was less with treatment.
                Laser photocoagulation of confluent soft macular drusen may improve long-term visual prognosis. To report the results of 12-month wear of three novel spectacle lens designs intended to reduce peripheral hyperopic defocus and one standard design control lens and their effect on the progression of myopia in Chinese children aged 6 to 16 years.
                Chinese children (n = 210) with myopia (-0.75 D to -3.50 D sphere, cylinder <or=-1.50 D) were randomized to one of four groups wearing either one of three novel spectacle lens designs (types I, II, or III) or conventional, single-vision spectacle lenses. Data were collected at 6 and 12 months. Primary and secondary outcome measures were the changes in central cycloplegic auto-refraction and eye axial length, respectively. Peripheral refraction along the horizontal meridian (nasal and temporal) was taken at baseline with and without spectacle lenses. Multivariate linear regression was used to adjust analyses for important covariates.
                Progression in eyes wearing control spectacle lenses at 6 and 12 months was -0.55 D +/- 0.35 D and -0.78 +/- 0.50 D, respectively. For the entire group, no statistically significant differences were observed in the rates of progression with the novel designs in comparison to control spectacle lenses. However, in younger children (6 to 12 years) with parental history of myopia (n = 100), there was significantly less progression (-0.68 D +/- 0.47 D vs. -0.97 D +/- 0.48 D) with lens type III compared with control spectacles (mean difference, 0.29 D, std error, 0.11, p = 0.038).
                There were no statistically significant differences in the rate of progression of myopia between the control and novel lens wearing eyes for the age group 6 to 16 years. The finding of reduced progression of myopia with type III lens design in younger children with parental myopia needs to be validated in a more targeted study. Undercorrection has recently been found to enhance the rate of progression of myopia. This result was thought to be controversial as it contrasted with expectations based on animal studies, as well as the results found wearing progressive addition lenses. The aim of the present study was to again determine the effect of undercorrection on the progression of myopia in a random population of children who are known to be very susceptible to myopia.
                A cohort of 48 myopic children, aged six to 15 years was randomly assigned to either a fully corrected group (n = 23) or to an undercorrected group (n = 25). The subjects in the latter group were blurred by +0.50 D. The prospective study extended over a period of 18 months. Optometric examinations were carried out at the beginning of the study, then at six-month, 12-month and 18-month follow-up.
                Undercorrection produced a slight but not statistically significant increase in myopic progression over the 18-month period equal to 0.17 D, compared to full correction. A similar trend towards an increase in progression was noted in females and in children with near esophoria.
                This study supports the evidence that undercorrection does not represent an effective therapy to slow the rate of early-onset myopic progression, regardless of near heterophoria.
The most likely effective treatment to slow myopia progression thus far is anti-muscarinic topical medication. However, side effects of these medications include light sensitivity and near blur. Also, they are not yet commercially available, so their use is limited and not practical. Further information is required for other methods of myopia control, such as the use of corneal reshaping contact lenses or bifocal soft contact lenses (BSCLs) with a distance center are promising, but currently no published randomized clinical trials exist.