Search

Purpose: to evaluate the effect of wearing glasses with Stellest® lenses on the spherical equivalent of refraction (SER) dynamics, the yearly progression gradient (YPG) and the axial length (AL) of the eye in children with progressive myopia 12, 18 and 24 months after the start of use. Material and methods. The main and the control groups of the study included children aged 8 to 13 years with low to moderate myopia at the beginning of observation. Stellest® glasses (the main group) were prescribed to 35 children with myopia 3.15 ± 0.19 D, while single vision (SV) glasses (the control group) were prescribed to 32 children with myopia 2.68 ± 0.18 D. The dynamics of the SER, YPG, and AL of the eye were assessed. Results. In the main (Stellest®) group, after 24 months of observation, SER increased by ave. 0.20 ± 0.06 D. YPG was shown to decrease in 93.5 % of cases by ave. 0.81 ± 0.05 D. The AL increased by an average of 0.15 ± 0.03 mm. In the control group, after 24 months of observation, the SER averaged 0.95 ± 0.08 D. YPG showed a decrease of ave. 0.38 ± 0.05 D in 61.1 % of cases. The AL of the eye increased by an average of 0.48 ± 0.04 mm. Conclusion. Stellest® glasses, if worn constantly, effectively slow myopia progression and axial elongation as compared with SV glasses. By the end of the follow-up period, in the Stelest® group, SER showed an increase by 79 % less than in the control group of SV glasses, and the AL showed increase in the length of the eye which was 69 % less than in the control group. Over the 24 months’ wearing of Stellest® glasses, YPG turned out to be 4.8 times lower than in the control group.

The article discusses the main etiological factors in the development of binocular diplopia and differential diagnostic signs of diplopia induced by late acquired comitant and incomitant strabismus.Purpose: to identify the most common causes of binocular diplopia in adults, and to assess typical features of various etiologies of binocular diplopia.Material and methods. 168 patients with binocular diplopia aged 6.5 to 85 years received a complete ophthalmological examination, which included a qualitative evaluation and characterization of the nature of diplopia, and determination of eye mobility in eight directions of gaze which indicated the affected muscle. A numerical assessment of diplopia was done using a prismatic compensator.Results. In 66.7% of cases, diplopia was induced by comitant strabismus, predominantly (96.4%) the converging one. A comitant strabismus with a small angle was observed more frequently than one with a larger angle: 5° or less, in 50% of cases, and 10° or less in 25% of cases. In 64.3% of cases, the deviation angle did not conform with the value of the compensating prism, which turned out to be twice as high as the “calculated values”. In 79.5% of cases, diplopia induced by comitant strabismus developed before the age of 45. In 33.3% of cases, diplopia was induced by incomitant strabismus, with the deviation angle varying from 0 to 35°, different directions of eye deviation, and limitation of mobility. In 44.6% of cases, mobility restrictions could not be visually detected. The deflection angle conformed to the strength of the compensating prism. In 58.9% of cases, diplopia induced by incomitant strabismus developed at the age of 45 years and older.Conclusion. Diplopia frequently develops in young and middle-aged people. The most common cause of the development of diplopia is a late acquired comitant converging strabismus with a small angle (5° or less), which develops in parallel with myopia. A correct identification of strabismus nature (comitant vs. incomitant), which induces diplopia, contributes to optimally choosing a further tactics for diplopia elimination.

Purpose: to evaluate near visual work performance of those wearing spectacles with Stellest™ lenses and the impact of their continuous wear on refraction changes, accommodation and binocular interaction after 6 months from the start of use. Material and methods. 35 children aged 8-13 with myopia of 3.15 ± 0.19 D were prescribed eyeglasses with Stellest™ lenses. 32 children with myopia of 2.68 ± 0.18 D who used monofocal glasses served as control. Visual performance, refraction, axial length (AL), accommodation and binocular interaction were assessed. Results. According to the Burdon test, the number of errors in counting letters in Stellest™ glasses was 4.5 ± 0.64, whilst in monofocal glasses it was- significantly less, 2.96 ± 0.42 (p < 0.05); the rate of test progress was the same in the two groups. After 6 months from the start of wearing Stellest™ glasses, the objective cycloplegic refraction increased by 0.11 ± 0.04 D, the average year progression rate (YPR) was 0.22 ± 0.08 D. In contrast, the children wearing monofocal glasses showed an average refraction increase of 0.35 ± 0.05 D, and the average YPR value of 0.7 ± 0.09 D. In the Stellest™group, YPG drop was observed in 87 % of cases and averaged 0.95 ± 0.11 D. In the control group, YPR was found to drop in 65 % of cases and averaged 0.49 ± 0.1 D. In the Stellest™ group, AL increased by 0.04 ± 0.02 mm; in the control group, the increase in AL was 2.8 times greater — by 0.11 ± 0.02 mm (p < 0.01). In the Stellest™ group, relative accommodation reserves (RAR) increased by 0.88 ± 0.14 D, which is significantly higher than in the group wearing monofocal glasses, where the increase was 0.39 ± 0.12 D (p < 0.01). No differences were revealed between the groups in objective indicators of accommodation and binocular interaction. Conclusion. Wearing spectacles with Stellest™ lenses for 6 months contributes to slowing down the progression of myopia in children. Over the observation period, the refraction increase in the main group was 3.2 times lower than in the control group, whilst AL growth was 2.8 times lower than that in the control group. The children using spectacles with Stellest™ lenses showed a higher increase in RAR as compared to children wearing monofocal spectacles. The accommodation tone and objective accommodation parameters were essentially the same in both groups. Wearing Stellest™ glasses had no pronounced effect on binocular interaction.

The article presents a theoretical and clinical justification for optical techniques used for the prevention of myopia. Accommodation, wavefront aberrations, peripheral refraction, and retinal image quality are considered as interrelated factors affecting postnatal refractogenesis. A detailed analysis of myopia correction methods, conditions preceding its development and their impact on the dynamics of refraction and eye growth is given. A strategy of optical correction of myopia was proposed, which includes: 1) constant wearing of defocusing binocular positive spectacle lens or Perifocal-P spectacle lens (in case of exophoria) for children at risk aged 4–7 years; 2) constant alternating weak myopic defocusing in case of myopia from 0.5 to 2.75 D, ortho- or esophoria, positive relative accommodation (PRA), peripheral myopia or emmetropia; progressive addition spectacle lens in case of PRA less than 1.0 D; Perifocal-Msa spectacle lens in the case of a combination of reduced PRA and exophoria; 3) Perifocal-M spectacle lens in case of myopia of any degree with already existing hyperopic peripheral defocus; progressive addition spectacle lens in case of PRA less than 1.0 D in combination with esophoria or Perifocal-Msa spectacle lens in combination with exophoria; 4) contact correction with bifocal soft contact lenses or orthokeratological contact lenses (Ortho-K) in case of refusal from spectacle correction. Ortho-K is preferable with moderate and high myopia; 5) bioptic correction: a combination of monofocal soft contact lenses and Perifocal-M spectacle lens to correct peripheral defocus and residual astigmatism is preferable for myopia over 8.0 D and myopia with astigmatism.

The purpose of the work was to study peripheral refraction in myopic patients without correction, in soft contact lenses (SCL), in monofocal glasses, and in Perifocal-M glasses.Material and methods. A total of 97 patients (184 eyes) aged 9–18 years with various degrees of myopia were examined. The peripheral refraction was measured using a Grand Seiko WR-5100K binocular open-field autorefractometer without correction, in glasses, and in the SCL. For the eviation of gaze, a nozzle was designed, which was attached to the device stand at a distance of 50 cm from the patient's eyes. On the nozzle, there were 4 marks for fixing the gaze in the position of 15° and 30° to the nose (N) and to the temple (T) from the central position.Results. In patients with myopia of various degrees without correction and with correction by monofocal glasses, hyperopic defocus formed in all zones on average. In eyes that were corrected with SCL and were mildly myopic in all zones, hyperopic defocus was detected. In moderate myopia, myopic defocus was detected in the zones T30° and N30°. With a high degree of myopia, myopic defocus was detected on the periphery in all zones except T15°, reaching -2.23 ± 1.35 D in the T30° zone and -1.56 ± 0.82 D in the N30° zone. In Perifocal-M glasses, myopic defocus formed in mildly myopic eyes: in the T15° zone its value was -0.95 ± 0.12 D, -0.24 ± 0.05 D in the N15° zone, and -1.14 ± 0.13 D in the T30° zone. Hyperopic defocus was observed only in the zone at N30°, and its value was minimal compared to other types of correction which was 0.13 ± 0.05 D. In moderate myopia, myopic defocus was observed only in the zone N15° at -0.28 ± 0.04 D. In all other zones, hyperopic defocus remained, but its magnitude was minimal compared to monofocal glasses: 0.6 ± 0.1 D at T30°, 0.05 ± 0.04 D at T15°, and 0.74 ± 0.11 D at N30°. Conclusion. In relation to peripheral defocus, perifocal glasses have an advantage in correcting myopia of a low and, in part, moderate degree.

According to the definition of the Expert council on accommodation and refraction, asthenopia is a functional disorder of vision with typical symptoms manifested in the fact that visual work becomes difficult or impossible. The paper suggests a classification of asthenopias which generalizes literary data and takes account of the authors’ own research results. The classification distinguishes among four forms of asthenopia, depending on the causes inducing the condition: accommodative (or refractive-accommodative), muscular (motoric), sensory (neuroreceptive) and psycho-emotional asthenopia. We also propose to distinguish three stages of asthenopia with regard to the severity of the symptoms: compensation, subcompensation, and decompensation stages // Russian Ophthalmological Journal, 2016; 4: 69-73. doi: 10.21516/2072-0076-2016-9-4-69-73 .

The review gives a detailed account of research data on myopia predictors. The most reliable predictors include cycloplegic sphere equivalent of axial refraction less than +0.75 D in children under 6 years, the axial length of more than 23.5 mm with the refractive error ≤ +1.0 D, myopic parents, axial length / corneal radius ratio (AL/CR) of less than 3, AC/A ratio over 4 Δ/D, pseudomyopia, heterophoria of more than 4 Δ, peripheral refraction of the nasal half of the eye at 20-30° higher than the temporal refraction in both eyes more than 0.5 D, reduced outdoor activity and high visual activity. Measures of prevention of myopia development are presented: adhering to the regiment of visual activity load, ergonomic stereotypes of near visual work, creation of binocular central and peripheral myopic defocus - positive spectacles or spectacles with Perifocal-P lenses with a central refraction of +0.25 D for permanent wear, home accommodative training exercises, physical exercises and sports, outdoor activity at least 90 minutes a day during daylight hours. For citation: Tarutta E.P., Proskurina O.V., Tarasova N.A., Ibatulin R.A., Kovychev A.S. Myopia predictors as a starting point for active prevention of myopia development. Russian ophthalmological journal. 2018; 11 (3): 107-12 (In Russian). doi: 10.21516/2072-0076-2018-11-3-107-112