[Correlation of chorioretinal parameters with anatomical, optical and functional indicators of eyes with amblyopia of various origins]. / Korrelyatsiya khorioretinal'nykh parametrov s anatomo-opticheskimi i funktsional'nymi pokazatelyami pri ambliopii razlichnogo geneza.

Purpose. To measure thickness of the central retina and choroid, retinal nerve fiber layer and ganglion cell complex in the macular region, retinal nerve fiber layer in the peripapillary region in eyes with various types of amblyopia, and to analyze its relationship with best corrected visual acuity, refraction and axial eye length. MATERIAL AND METHODS: The study included 50 patients aged 5 to 16 years (mean age 10.04±3.01 years). All patients were divided into 6 groups: 1 - relative amblyopia with congenital myopia (23 eyes); 2 - dysbinocular amblyopia (14 eyes); 3 - refractive amblyopia (16 eyes); 4 - anisometropic amblyopia (7 eyes); 5 - paired eyes of patients with amblyopia (20 eyes); 6 - control group (20 eyes). Chorioretinal parameters were determined using the RS-3000 Advance 2 spectral optical coherence tomography system («Nidek¼, Japan). Correlation analysis was performed using the Pearson's linear correlation coefficient (r). The level of significance of the differences was determined by the standard Student's t-test. RESULTS: Morphological changes in the sensory and choroid membranes of the eye were revealed in groups with amblyopia of various origins compared to the control group, as well as in the fellow eyes. Intergroup comparison showed the presence of more significant disorders in refractive and relative amblyopia due to congenital myopia. Correlation analysis showed that structural changes in the posterior pole are more related to the anatomical and optical parameters of the eyes. CONCLUSION: Optical coherence tomography allows detection of microscopic structural anomalies in the posterior pole of the eye in amblyopia of various origins, assists in differential diagnosis of this condition with organic pathology, and - most importantly - helps peer deeper into the pathogenesis of this disease.

[Correlations between visual fixation parameters, photosensitivity of the retina and visual acuity in various types of amblyopia]. / Vzaimosvyaz' parametrov zritel'noi fiksatsii, svetochuvstvitel'nosti setchatki i ostroty zreniya pri razlichnykh vidakh ambliopii.

PURPOSE: To study the parameters of visual fixation, photosensitivity in the macular region of the retina, and their correlation with the best-corrected visual acuity (BCVA) for various types of amblyopia. MATERIAL AND METHODS: The study included 50 patients with an average age of 11.02±4.2 years. All patients were divided into 3 groups depending on amblyopia type; group 4 consisted of the paired eyes of patients with amblyopia; group 5 was the control group. Retinal photosensitivity and fixation parameters were studied on the Nidek MP-3 microperimeter (Japan). Correlation analysis was performed using the linear Pearson correlation coefficient (r). RESULTS: Retinal photosensitivity was the lowest in the groups with relative amblyopia with nystagmus (25.7±3.6 dB; group 3) and congenital myopia (26.1±2.9 dB; group 2), which is consistent with the partially organic nature of relative amblyopia. In the group with strabismic and refractive amblyopia (group 1), photosensitivity did not significantly differ from the control group (p>0.05). Fixation density was the lowest in the first (85.1±0.2% and 92.8±0.16% at 2° and 4°, respectively) and the third (62.6±0.16% and 89.3±0.05% in 2° and 4°, respectively) groups. In the first group, a strong correlation (r=0.77) of the fixation density and BCVA was revealed; no such correlation was observed in groups 2 and 3. No correlation of photosensitivity and BCVA was detected in group 1 (r=0.2). Fixation density in the group of paired eyes was significantly lower than in the control group (p<0.001). CONCLUSION: Microperimetry is an innovative tool for differential diagnosis, monitoring, method selection and evaluation of the effectiveness of treatment of various types of amblyopia.

[Choroid and optical defocus]. / Khorioideya i opticheskii defokus.

The review summarizes experimental and clinical data attesting to the important role the choroid plays in the development of refraction through optically oriented thickness changes and the release of growth factors. Because of its unique anatomical position, the choroid can influence the transmission of a cascade of chemical signals from the retina to the sclera and thereby affect the growth of the eye. Understanding the relationship between the optical defocus and the response of the choroid to it will help uncover the fundamental mechanisms for controlling eye growth and develop new strategies for preventing the progression of myopia.

[Long-term results of perifocal defocus spectacle lens correction in children with progressive myopia]. / Otdalennye rezul'taty ochkovoi korrektsii s perifokal'nym defokusom u detei s progressiruiushchei miopiei.

Peripheral defocus plays a significant role in the formation of refraction. Perifocal spectacles allow differentiating correction of central and peripheral refraction of the eye along the horizontal meridian and can correct or reduce peripheral hyperopia. PURPOSE: To study the long-term results of wearing perifocal spectacles on the refraction in children with progressive myopia. MATERIAL AND METHODS: Perifocal spectacles were assigned to children of 7-14 years old with progressive myopia from -1.0 to -6.0 D in terms of refractive spherical equivalent. The children were examined before the prescription of perifocal spectacles and after 6 months, 12-18 months, 2 years, 3 years and 4-5 years. We measured visual acuity, the character of vision, refractive error before and after cycloplegia, performed biomicroscopy, ophthalmoscopy and biometry. Peripheral refraction was studied at 15° and 30° points in the nasal (N15 and N30) and temporal (T15 and T30) meridians without correction and while wearing perifocal spectacles. RESULTS: In perifocal spectacles, in the 15° zone, 100% of the eyes formed myopic defocus, which averaged -0.05±0.1 D in T15°, -0.25±0.16 D in N15° and -0.44±0.03 D in T30°. In the N30° zone, the hypermetropic defocus decreased by 4 times and amounted to 0.38±0.03 D. The rate of progression of myopia decreased from 0.8 D of baseline values to 0.17 D at 4-5 years of follow-up. After 6 months of wearing perifocal spectacles, the refraction gain was -0.2±0.02 D (in the control group it was -0.38±0.04 D), after 12-18 months - (-)0.38±0.04 D (-0.63±0.09 D in the control group), after 2 years - (-)0,78±0,06 D (-1.18±0,15 D in the control group), after 3 years - (-)0.99±0.12 D (-1.65±0.20D in the control group). During the 4-5 years of the follow-up, the refractive error in the main group was -1.16±0.2 D, which is 60% less than in the control group (-1.95±0.2 D). CONCLUSION: Constant wearing of perifocal spectacles reduces the rate of myopia progression in children by 4.5 times compared with the initial rate, and by 1.6 times (by 60%) in comparison with the control group. Perifocal spectacles are recommended as optical means to slow the progression of myopia.

[Peripheral refraction and retinal contour in congenital and acquired high myopia]. / Perifericheskaia refraktsiia i kontur setchatki pri vrozhdennoi i priobretennoi miopii vysokoi stepeni.

AIM: to perform a comparative study of peripheral refraction and retinal contour in patients with congenital versus acquired high myopia. MATERIAL AND METHODS: A total of 30 patients (60 eyes) with high myopia aged 8 to 18 years (11.2±0.32 years on average) were examined. The patients were divided into 2 groups. Group 1 consisted of 21 patients (42 eyes) with acquired myopia of -6.0 to -10.25 diopters (-7.55±0.17 diopters on average), group 2 - of 9 patients (18 eyes) with congenital myopia of -8.75 to -28.75 diopters (-16.39±1.24 diopters on average). Using the Grand Seiko WR-5100K binocular open-field autoref/keratometer (Japan), relative peripheral refraction was assessed with account to relative peripheral eye length measured by the IOL Master partial coherent interferometer ('Carl Zeiss', Germany) at 15° and 30° nasally and temporally from the foveal center along the horizontal meridian. RESULTS: In acquired myopia, relative peripheral refraction and relative peripheral eye length readings evidenced the formation of peripheral hyperopic defocus in all examined zones. Congenital high myopia cases were notable for myopic defocus at 15° of the nasal retina (N15 zone): -0.67±0.33 diopters against the eye length change of -0.33±0.13 mm. CONCLUSION: The research helped identify retinal contour changes characteristic of congenital myopia and indicative of posterior pole irregularity.

[Transpalpebral Tetrapolar Reoophtalmography in the Assessment of Parameters of the Eye Blood Circulatory System].

BACKGROUND: Quantitative assessment of hemodynamic parameters is an important element of ophthalmic diagnostics especially in early detection of myopia, glaucoma, diabetic retinopathy. The assessment of hemodynamic changes is essential in evaluating of the efficiency of treatment. Objective: Our aim was to determine the adequate of eye hemodynamics assessment using reoophtalmography in patients with various clinical refractions. METHODS: A controlled study was carried out. All tests were performed using transpalpebral tetrapolar method. Signal registration lasted for 20 seconds in the supine position, and then the diagnostic parameters were calculated. RESULTS: We present the results of examination of 76 patients aged 5 to 22 years (average age 13.0 ± 1.1). 32 patients had low myopia (62 reoophtalmography records), 23 patients had moderate myopia (42 records) and 5 patients had high myopia (12 records). The control group was composed of 16 patients. The main differences were found in the rheographic index, which is equal to 58.1 ± 4.1 mOhm in the control group. It is significantly reducing with refraction increase, from 47.8 ± 3.2 mOhm in low myopia to 34.0 ± 2.5 mOhm in high myopia (p = 0.050). This is an evidence of blood supply deficiency in the myopic eyes. CONCLUSION: Rheographic index was shown to differ in different breathing phases, which agrees with the known physiological regularities. The proposed method is highly informative and sufficiently accurate what allows assessing the eye blood supply state objectively. It is easy to apply and requires no contact with the eye surface, which is especially important in pediatric practice.