Bifocal Soft Contact Research Articles

Optical methods for the management of progressive myopia

Introduction. Myopia is the main cause of preventable blindness and is widespread around the world at an alarming rate, especially in Asian countries. The age of the onset of myopia is getting younger. The prevalence of myopia and high myopia is sharply increasing, which requires clinicians to use new and safe methods of its stabilization. The main methods of correction are optical. This group is based on the hypothesis of induced peripheral myopic defocus.Aim: to study the domestic and international experience with the use of the optical methods in treatment of progressive myopia according to the literature and factors, as well as factors affecting their effectiveness.Materials and methods. More than 200 publications on PubMed, eLibrary, and Crossref Metadata over the past 10 years were analyzed. Our analysis includes a review of 60 publications.Results. Over the past years, there has been a strong interest of researchers in the problem of progressive myopia. This is reflected by a more than four-fold increase in the number of publications devoted to the causes and methods of treatment in patients with progressive myopia. Publications demonstrate the importance of using the modern optical methods, such as spectacle lenses, multifocal and bifocal soft contact lenses and orthokeratology in the routine practice of ophthalmologists and optometrists in order to stabilize the progression of myopia in children and adolescents. On the one hand, the results of analysis show their high efficiency. On the other hand, we need an individual approach in choosing the method for myopia control in each specific case. The factors influencing the result are identified: the diameter of the optical zone, the force of addition that creates the peripheral myopic defocus and the time of use myopia correction during the day.Conclusion. No method of treating progressive myopia demonstrates clear superiority. Orthokeratology, multifocal and bifocal soft contact lenses, special glasses and low doses atropine instillation demonstrates the similar effect with some clauses. When choosing optical methods for myopia control, the factors affecting their effectiveness should be taken into account.

Induced bifocal soft contact lenses with the addition of 4.0 D myopic defocus in the near periphery of the retina and its effect on the progression of myopia

AIM: To evaluate the dynamics of axial and peripheral refraction in the near periphery of the retina in eyes with myopia against the background of wearing bifocal soft contact lens (BSCL) with the addition of 4 D.
 MATERIAL AND METHODS: Forty-three patients (84 eyes) with myopia from 0.5 to 6.5 D (average 3.530.19 D) aged 715 (average 11.30.27) years were examined before and 6 months after the start of wearing Prima BIO Bifocal BSCL (Okey Vision Retail, Russia). Visual acuity without correction, with optimal correction, and in BSCL, cycloplegic refraction, eye length, keratotopography, and peripheral defocus (PD) at 5, 10, and 15 to the nose and temple from the center of the fovea with and without lenses were assessed.
 RESULTS: After 6 months of wearing BSCL, the subjective refraction increased by 0.04 D, cycloplegic refraction by 0.18 D, and average BSCL strength by 0.01 D. The axial length increased by 0.03 mm (p 0.05). The initial PD without lenses was hypermetropic in all zones, and in BSCL, it was myopic in zones T5, T10, T15, and N15 and hypermetropic in zones N5 and N10. After 6 months of PD without correction, hypermetropic defocus tended to decrease in zones N10 and N15 and myopic defocus appeared in N5 (p 0.05); with lenses, myopic defocus increased in zones T5, T10, T15, and N15, and in N5 and N10, it did not change and remained hypermetropic.
 CONCLUSION: BSCLs provide total correction of myopia and high distant and near visual acuity in children, induce myopic defocus in the near periphery, and contribute to the inhibition of the progression of myopia in the traced period.

Changes in the Axial Length of the Eye and Refraction in Children with Progressive Myopia while Wearing Defocused Contact Lenses

Progressive myopia remains one of the urgent problems in modern ophthalmology. Optical methods for controlling progressive myopia suggest the formation of peripheral myopic defocus, which has a stabilizing effect on the axial length of the eye and, as a result, the degree of myopia. One option for optical control of myopia is defocus soft contact lenses.Purpose: to evaluate the growth of axial length and changes in the spherical equivalent of clinical refraction in users of defocus (bifocal) contact lenses and monofocal glasses expressed in diopters, against the background of the correction of progressive myopia with defocus (bifocal) contact lenses and monofocal glasses.Materials and methods. The study involved 256 patients with bilateral mild to moderate and high myopia in the range from (–)0.5 to (–) 7.75 D in spherical equivalent and an annual progression gradient from 0.65 to 1.5 D in the age categories 7–10, 11–14, 15–18 years old. Depending on the degree of myopia and the method of correction, the patients were divided into main and control groups. For correction in the main groups, defocused (with an addition of +4.0 D) soft contact lenses (SCLs) were used. In the control groups monofocal glasses were used. All patients underwent a standard ophthalmological examination. Clinical refraction data and axial length of the eye were used as criteria for evaluating the results. The follow-up period was 3, 6, 12 months.Results. After 12 months of wearing bifocal soft contact lenses, there was a statistically significant slowdown in the growth of the axial length and the spherical equivalent of refraction Higher rates of progression of myopia were in young children (7–10 years). Myopia at the age of 15–18 years is characterized by a decrease in the rate of progression with any type of optical correction and in most cases does not require the appointment of correction with the formation of peripheral myopic defocus.Conclusion. The results obtained indicate the effectiveness of the use of bifocal SCLs in the control of progressive mild, moderate and high myopia. The main stabilization factor is the formation of peripheral myopic defocus on the retina, followed by a slowdown in the growth of the axial length of the eye and the degree of myopia (spherical equivalent of clinical refraction).

The issue of juvenile myopia from the parents’ point of view

The success of preventing the development and progression of myopia in children depends on establishing compliance between the doctor and the patient (parents).Purpose: to study the attitude of parents of myopic children towards the issue of myopia and methods of its control.Materials and methods. 106 doctors from 53 regions of Russia and 2931 parents of myopic children took part in a prospective multicenter epidemiological observational study in the form of a questionnaire.Results. As preferable interventions to control myopia, parents mention single vision glasses (67.9 %), glasses with perifocal lenses (16.3 %), bifocal or progressive glasses (3.4 %), other types of glasses (1.6 %), soft contact lenses (11.5 %), orthokeratology lenses (5.8 %), while 13.8 % of myopic children do not use any of those. The average time that children spend on visual work amounts to 10 hours a day, while their light-time daily outdoor activities last for 2.12 ± 1.39 hours. Only 27.1 % of the parents surveyed follow all recommendations of the eye doctor. The reasons for not following are lack of time (45.1 %), complexity of implementation (7.3 %), high cost of treatment (8.5 %), other reasons (39.1 %). Parents consider that the most effective interventions to control myopia are eye drops instillation courses (53.4 %), device-assisted therapy (59.6 %), home visual gymnastics (52.4 %), orthokeratology lenses (13.7 %), bifocal soft contact lenses (4.6 %), specialty glasses (22.7 %), vitamins intake (44.4 %), while 10.6 % believe opinion that no effective myopia control methods exist.Conclusion. Parents choose single vision glasses as the main optical interventi on method. Near visual work significantly reduces physical activity in the children’s daily routine. Parents’ failure to comply with the medical advice is mostly due to lack of time. The most effective methods of myopia control are considered to be pharmacological treatment, device-assisted therapy and home visual gymnastics.

The effect of optic zone diameter on choroidal response using bifocal soft multifocal contact lenses

The effect of optic zone diameter on choroidal response using bifocal soft multifocal contact lenses

Changes in subfoveal choroidal thickness in myopic children who wear bifocal soft contact lenses

To study the changes in subfoveal choroidal thickness in children with progressive myopia who have been wearing bifocal soft contact lenses (BSCL) with an ADD power of +4.0 D for 3 months. The study included 40 patients (80 eyes) with progressive myopia of low and moderate degrees. The main group consisted of 23 patients aged 10.04±1.5 years with an average myopia of -3.06±1.17 D, they were examined before and 3 months after vision correction with bifocal soft contact lenses Prima BIO Bi-focal («OkVision Retail», Russia). The control group consisted of 17 patients (34 eyes) aged 9.29±0.92 years with an average myopia of -3.05±1.5 D using single vision spectacle lenses. Cycloplegic refraction, choroidal thickness and axial length were measured in all patients before and after 3 months. Choroidal thickness was measured using the semi-automatic method on the optical coherent tomography system RS-3000 Advance 2 («Nidek», Japan). Axial length was measured using the optical biometer IOL Master 500 («Carl Zeiss», Germany). In the main group, subfoveolar choroidal thickness increased on average by 15.3±24.3 μm after 3 months of wearing BSCL, and in the control group it decreased on average by 9.03±28.65 μm. Comparison of changes in choroidal thickness between the main and the control groups revealed a significant difference (p<0.001). Increase in axial length of the eye in the main group was significantly less than in the control group (0.005±0.08 mm vs 0.07±0.06 mm; p<0.001). A strong negative correlation was found between changes in the axial length and subfoveolar choroidal thickness in the main group (r= -0.67), but no similar relationship was found in the control group (r= -0.13). Subfoveolar choroidal thickness increases in children wearing bifocal soft contact lenses for myopia correction.

Peripheral Refraction, Wave Front of the Eye and Visual Performance in the Correction of Myopia in Children with Bifocal Soft Contact Lenses with High Addition

Purpose: to study the effect of bifocal soft contact lens (BSCL) with an ADD of 4 diopters on peripheral refraction (PR), optical and ergonomic eye parameters in children with myopia.Patients and methods. 26 patients (52 eyes) with myopia –3.09 ± 1.13 diopters at the age of 10.04 ± 1.5 years without correction and with correction by BSCL Prima BIO Bi-focal ( Okay Vision Retail, Russia). All patients underwent a horizontal and vertical PR study on an open field autorefractometer Grand Seiko WAM-5500 (Japan), wavefront aberrations were studied on OPD-Scan III aberrometer (Nidek, Japan), contrast sensitivity under mesopic conditions were studied on a Mesotest 2 instrument (Oculus, Germany) and visual productivity was studied using test tables.Results. The visual acuity of the distance with a BSCL correction of 0.98 ± 0.04 did not differ (p = 0.26) from the maximum visual acuity corrected by spherocylindrical glasses of 0.99 ± 0.04. BSCL induces myopic defocus in all peripheral zones, with a maximum value of 15° and a sharp decrease of 30°. Peripheral myopic defocus induced by the lens at a horizontal and vertical angle of 15 degrees did not depend on the initial degree of myopia. BSCL increases the total RMS from 0.07 ± 0.02 μm to 0.19 ± 0.07 μm in the 3 mm zone (p &lt; 0.01) and from 0.27 ± 0.09 μm to 1.18 ± 0, 23 μm in the 6 mm zone (p &lt; 0.01), mainly due to an increase in spherical aberration from –0.0005 ± 0.006 μm to 0.06 ± 0.01 μm (p &lt; 0.01) and from 0.01 ± 0.09 μm to 0.58 ± 0.14 μm (p &lt; 0.01) in the 3 mm and 6 mm zones, respectively. An increase in the overall RMS in BSCL reduces the quality of eye optics and contrast sensitivity under mesopic conditions, but does not impair visual productivity.Conclusion. BSCLs with a high ADD of 4 diopters are capable of inducing significant myopic peripheral defocus due to the induction of spherical aberration, while maintaining high visual acuity and not changing ophthalmic ergonomics, which makes them a pathogenetically substantiated method for correcting myopia and preventing its progression in children and adolescents.

Our Experience of Using Soft Bifocal Contact Lenses in Children with Progressive Myopia

Introduction. According to the studies, one out of three myopic patients with refraction greater than –6.00 D and an axial length greater than 26 mm is at high risk of facing low vision and loss of sight in the future. According to the results of medical examinations and screenings in carried out in Ivanovo, the prevalence of myopia in primary school children has increased three times during the past twenty years. Myopic children under 7 years old are six times more likely to have myopia progressed to higher degrees than children in which myopia onset took place later (at the age of 11–12 years). Optical interventions for myopia control such as orthokeratology and soft bifocal contact lenses have a strong body of evidence and are well accepted by ophthalmologists.Purpose. The purpose of the present study was to investigate the effect of soft bifocal contact lenses on refraction, accommodation and axial length in children with progressive myopia.Materials and methods. We observed 30 children aged 8–15 years with myopia progression rate of 0.82 D/year and accommodative weakness and instability. We prescribed OKVision PrimaBio Bi-focal design soft bifocal contact lenses (OKVision, Russia) that feature +4.00 D addition power on periphery. The effectiveness was estimated by monitoring refraction, accommodation and axial length every three months within a year.Results. After 12 months of wearing soft bifocal contact lenses, the annual myopia progression rate decreased 4.3 times on average. We were able to stabilize myopia in 50% of the children during the period of monitoring. The use of this intervention had a strong effect on accommodation resulting in an increase of its amplitude and reserve.Conclusion. The use of soft bifocal contact lenses has been proven to have a strong inhibitory effect on myopia progression rate. Myopia stabilization manifested itself as the absence of increase in myopic refraction and axial length as well as normalization of accommodative function.

Epidemiology of Myopia in Children of the Russian Federation and Analysis of Its Control Methods

The increasing prevalence of myopia is observed all over the world, and Russia is no exception. In this regard, obtaining new data on its epidemiology among children and assessing methods of its control in real clinical practice are highly topical matters.Purpose. The purpose of this work was to assess the current issues of the epidemiology and treatment of progressive myopia in children in various regions of the Russian Federation.Materials and methods. We conducted a prospective multicenter epidemiological observational questionnaire study. This study involved 106 doctors from 53 regions of Russia and 2931 parents of myopic children.Results. 50% of the surveyed doctors noted that the manifestation of myopia is diagnosed in children aged 10–12 years, while 43% noted the same in children aged 7–9 years. According to 74.5% of doctors, the degree of the newly diagnosed myopia ranges from –1.25 to –3.00 diopters, 25.5% of doctors reported that it is below –1.0 diopters. The majority of doctors (73.6%) assess accommodation in myopic children, considering it one of the progression factors. 52.9% of ophthalmologists prescribe optical correction in cases when monocular distance visual acuity amounts to 0.6 (decimal scale) or lower values, while 29.2%, 16% and 1.9% of the surveyed ophthalmologists prescribe optical correction in cases when monocular distance visual acuity amounts to 0.7, 0.8 and 0.9 respectively.The following optical methods for juvenile myopia control are recommended by the doctors: orthokeratology contact lenses (53.8%), spectacles for full correction (51.9%), peripheral defocus-inducing (bifocal) soft contact lenses (18.9%), while 4.7% of the surveyed doctors utilized other methods of myopia control, which were not indicated in the questionnaire.Conclusion. In most cases, manifestation of myopia is diagnosed in children aged 7–12 years. Its degree ranges from –1.25 to –3.0 diopters, which indicates its late diagnosis; optical correction is prescribed mainly in cases when monocular distance visual acuity is 0.6 or lower; most ophthalmologists assess accommodation in myopic children, considering it a progression factor. As methods of myopia control, doctors utilize optical correction, device-assisted therapy and pharmacological treatment of accommodative disorders, while parents prefer methods that require minimum time expenditures.

Влияние оптических методов коррекции на гармонизацию аккомодации у детей с прогрессирующей миопией

Accommodation disorders in young people are more common than diagnosed. This review is based on the data of domestic and foreign literature and studies the effect of contact lenses of various designs on accommodation. Particular attention has been given to bifocal soft contact lenses as one of the recognized interventions for treating juvenile progressive myopia and their ability to slow axial elongation. Key words: accommodation, myopia control, bifocal contact lenses, orthokeratology.

Accommodation Dynamics in Children Wearing Bifocal Soft Contact Lenses with High Addition Power

Purpose: to evaluate dynamics of subjective and objective accommodation in children wearing bifocal soft contact lenses (BSCLs) for myopia control with +4.00 D addition power. M e t h o d s: the study involved 22 patients (44 eyes).Mean age amounted to 10.1 ± 1.46 years and mean myopic refraction amounted to –3.21 ± 1.23 D. Patients were fitted Prima BIO Bi-focal BSCLs (OKVision Retail, Russia). All patients underwent cycloplegic refraction assessed with Auto Ref/Keratometer ARK 530A (Nidek, Japan), had axial length measured with IOL Master 500 optical biometry device (Carl Zeiss, Germany), had positive relative accommodation (PRA) assessed with and without lenses and had binocular (BAR) and monocular (MAR) accommodative response assessed at a distance of 33 cm with WAM-5500 Binocular Accommodation Auto Ref/Keratometer (Grand Seiko, Japan) prior to wearing BSCLs as well as 3, 6 and 12 months after wearing BSCLs.Results: neither MAR nor BAR measured without lenses changed after 3, 6 and 12 months of wearing BSCLs (p &gt;0,05). A change in PRA evaluated without lenses was noted after 12 months (p &lt; 0,05). PRA evaluated with lenses after 3, 6 and 12 months differed from baseline significantly (p &lt; 0,001). Over 12 months of wearing BSCLs, changes in AL (0.09 ± 0.17 mm) and cycloplegic refraction (0.3 ±0.43 D) correlated with baseline BAR and MAR loosely. C o n c l u s i o n: objective accommodation (MAR and BAR) did not change in the course of wearing BSCLs with +4.00 D addition power. Increase in PRA evaluated without BSCLs may be associated with improvement of accommodation due to a full correction in the optic zone. The gradual increase in PRA evaluated with BSCLs probably indicates an adaptation of patients to addition zone in near vision conditions.

Results of a two-year clinical study of myopia control with bifocal defocus-inducing soft contact lenses

To review the results of a two-year multicenter clinical study of myopia control with bifocal defocus-inducing SCLs. The two-year study enrolled 100 patients aged 8 to 16 years who had mild or moderate bilateral myopia with spherical equivalent of (-)0.25 to (-)5.75 D. Based on the degree of myopia and the method of its correction, patients were divided into two main and two control groups. Multifocal SCLs with +4.0 D add power and monofocal SCLs were used for myopia correction. The results were evaluated by the clinical data of refraction, axial length and state of accommodation. The observation times were 3, 6, 12, 18 and 24 months. After 12 months of bifocal SCLs usage, signs of stabilization of myopia progression were identified in 72 and 73.5% of subjects of both main groups, after 24 months - in 54 and 79.5% of subjects, respectively. Statistically significant reduction in axial elongation amounting to 87-88% was also observed in patients using bifocal SCLs. A significant increase in positive relative accommodation (PRA) was observed in all groups. The study indicates the effectiveness of bifocal soft contact lenses in slowing the progression of mild and moderate myopia.

CONTROLLING MYOPIA PROGRESSION IN CHILDREN

Main aim of this article was a systematic review on causes and management of Myopia progression in children. Myopia is a general disorder, affecting just about one-third of the US popula­tion and over 90% of the population in some East Asian countries. Elevated amounts of myopia are connected with a bigger risk of sight-threatening troubles, such as retinal detachment, choroidal degeneration, cataracts and glaucoma. Slowing the progression of myopia could potentially advantage millions of children in the India. Few approaches used for myopia organize have proven to be useful. Treatment options such as undercorrection of myopia, gas permeable contact lenses, and bifocal or multifocal spectacles have all been proven to be inef­fective for myopia control, although one recent randomized clinical trial using executive top bifocal spectacles on children with progressive myopia has shown to decrease the progression to nearly half of the control subjects. The most effective methods are the use of orthokeratology contact lenses, soft bifocal contact lenses, and pharmaceutical agents such as atropine, timolol or pirenzepine.&#x0D; Keyword: Myopia progression, pharmaceutical agents, lenses, treatment.

Interventions to slow progression of myopia in children.

Background Nearsightedness (myopia) causes blurry vision when looking at distant objects. Highly nearsighted people are at greater risk of several vision-threatening problems such as retinal detachments, choroidal atrophy, cataracts and glaucoma. Interventions that have been explored to slow the progression of myopia include bifocal spectacles, cycloplegic drops, intraocular pressure-lowering drugs, muscarinic receptor antagonists and contact lenses. The purpose of this review was to systematically assess the effectiveness of strategies to control progression of myopia in children.

Clinical evaluation of higher add bifocal soft contact lens to control axial length growth in myopic children

Clinical evaluation of higher add bifocal soft contact lens to control axial length growth in myopic children

Examination of Myopia Progression and Soft Bifocal Contact Lens Myopia Control

Examination of Myopia Progression and Soft Bifocal Contact Lens Myopia Control

Correcting progressive myopia with bifocal contact lenses with central zone for distant vision: changes in accommodation and axial length (a preliminary report)

To assess the state of accommodation and the dynamics of changes of ocular axial length in patients with progressive myopia who use bifocal soft contact lenses (BFSCLs). The main and control groups consisted of 50 children (100 eyes) each. Patients of the main group used BFSCLs with distance-oriented central zone and added power of 4 D on the periphery. Patients of the control group were corrected with spherical soft contact lenses (SSCLs). Baseline measurements included amplitude of accommodation (AA), positive relative accommodation (PRA) and the length of anterior-posterior axis of the eye. All patients were examined before wearing SCLs and every 3 months during the entire period of observation lasting 9 to 12 months. Correction of myopia with contact lenses is accompanied by the increase of AA and RPA. The users of BFSCLs with distance-oriented central zone and added power of 4 D on the periphery, which induces myopic peripheral defocus, had their accommodative function normalize much faster than the patients wearing SSCLs. The average increase in the ocular axial length in the BFSCLs group appeared to be significantly smaller than in the SSCLs group (0.11 and 0.58 D, respectively), which can be attributed to the simultaneous formation of the central focus and induced peripheral myopic defocus.

Through‐focus optical characteristics of monofocal and bifocal soft contact lenses across the peripheral visual field

To characterise the impact of monofocal soft contact lens (SCL) and bifocal SCLs on refractive error, depth of focus (DoF) and orientation of blur in the peripheral visual field. Monofocal and two bifocal SCLs, Acuvue Bifocal (AVB, Johnson & Johnson) and Misight Dual Focus (DF, CooperVision) with +2.0D add power were modelled using a ray tracing program (ZEMAX) based on their power maps. These SCLs were placed onto the anterior corneal surface of the simulated Atchison myopic eye model to correct for -3.0D spherical refractive error at the fovea. To quantify through-focus retinal image quality, defocus from -3.5D to 1.5D in 0.5D steps was induced at each horizontal eccentricity from 0 to 40° in 10° steps. Wavefront aberrations were computed for each visual eccentricity and defocus. The retinal images were simulated using a custom software program developed in Matlab (The MathWorks) by convolving the point spread function calculated from the aberration with a reference image. The convolved images were spatially filtered to match the spatial resolution limit of each peripheral eccentricity. Retinal image quality was then quantified by the 2-D cross-correlation between the filtered convolved retinal images and the reference image. Peripheral defocus, DoF and orientation of blur were also estimated. In comparison with the monofocal SCL, the bifocal SCLs degraded retinal image quality while DoF was increased at fovea. From 10 to 20°, a relatively small amount of myopic shift (less than 0.3D) was induced by bifocal SCLs compared with monofocal. DoF was also increased with bifocal SCLs at peripheral vision of 10 and 20°. The trend of myopic shift became less consistent at larger eccentricity, where at 30° DF showed a 0.75D myopic shift while AVB showed a 0.2D hyperopic shift and both AVB and DF exhibited large relative hyperopic defocus at 40°. The anisotropy in orientation of blur was found to increase and change its direction through focus beyond central vision. This trend was found to be less dominant with bifocal SCLs compared to monofocal SCL. Bifocal SCLs have a relatively small impact on myopic shift in peripheral refractive error while DoF is increased significantly. We hypothetically suggest that a mechanism underlying myopia control with these bifocal or multifocal contact lenses is an increase in DoF and a decrease in anisotropy of peripheral optical blur.

A Randomized Trial of Soft Multifocal Contact Lenses for Myopia Control: Baseline Data and Methods.

The Bifocal Lenses In Nearsighted Kids (BLINK) study is the first soft multifocal contact lens myopia control study to compare add powers and measure peripheral refractive error in the vertical meridian, so it will provide important information about the potential mechanism of myopia control. The BLINK study is a National Eye Institute-sponsored, double-masked, randomized clinical trial to investigate the effects of soft multifocal contact lenses on myopia progression. This article describes the subjects' baseline characteristics and study methods. Subjects were 7 to 11 years old, had -0.75 to -5.00 spherical component and less than 1.00 diopter (D) astigmatism, and had 20/25 or better logMAR distance visual acuity with manifest refraction in each eye and with +2.50-D add soft bifocal contact lenses on both eyes. Children were randomly assigned to wear Biofinity single-vision, Biofinity Multifocal "D" with a +1.50-D add power, or Biofinity Multifocal "D" with a +2.50-D add power contact lenses. We examined 443 subjects at the baseline visits, and 294 (66.4%) subjects were enrolled. Of the enrolled subjects, 177 (60.2%) were female, and 200 (68%) were white. The mean (± SD) age was 10.3 ± 1.2 years, and 117 (39.8%) of the eligible subjects were younger than 10 years. The mean spherical equivalent refractive error, measured by cycloplegic autorefraction was -2.39 ± 1.00 D. The best-corrected binocular logMAR visual acuity with glasses was +0.01 ± 0.06 (20/21) at distance and -0.03 ± 0.08 (20/18) at near. The BLINK study subjects are similar to patients who would routinely be eligible for myopia control in practice, so the results will provide clinical information about soft bifocal contact lens myopia control as well as information about the mechanism of the treatment effect, if one occurs.

Studies using concentric ring bifocal and peripheral add multifocal contact lenses to slow myopia progression in school-aged children: a meta-analysis.

To evaluate the effect of soft contact lens with concentric ring bifocal and peripheral add multifocal designs on controlling myopia progression in school-aged children. We systematically searched MEDLINE, EMBASE, Cochrane Library and reference lists of included trials. Methodological quality of included trials was assessed using Jadad Scale and Newcastle-Ottawa Quality Assessment Scale items. We identified five randomised controlled trials (RCTs) and three cohort studies with a total of 587 myopic children. Compared with the control group, concentric ring bifocal soft contact lenses showed less myopia progression with a weighted mean difference (WMD) of 0.31 D (95% CI, 0.05~0.57 D, p = 0.02) and less axial elongation with a WMD of -0.12 mm (95% CI, approximately -0.18 to -0.07 mm, p < 0.0001) at 12 months. Relative to the control group, peripheral add multifocal soft contact lenses showed less myopia progression with a WMD of 0.22 D (95% CI 0.14~0.31 D, p < 0.0001) and less axial elongation of -0.10 mm (95% CI -0.13~0.07 mm, p < 0.0001) at 12 months, respectively. The soft contact lenses with concentric ring bifocal and peripheral add multifocal designs produced additional myopia control rates of 30~38% for slowing myopia progression and 31~51% for lessening axial elongation within 24 months. Both concentric ring bifocal and peripheral add multifocal soft contact lenses are clinically effective for controlling myopia in school-aged children, with an overall myopia control rates of 30~50% over 2 years. Concentric ring bifocal soft contact lenses seem to have greater effect than peripheral add multifocal soft contact lenses.