We studied the emergence process of 42 active region (ARs) by analyzing the time derivative, R(t), of the total unsigned flux. Line-of-sight magnetograms acquired by the Helioseismic and Magnetic Imager (HMI) onboard the Solar Dynamics Observatory (SDO) were used. A continuous piecewise linear fitting to the R(t)-profile was applied to detect an interval, ∆t 2 , of nearly-constant R(t) covering one or several local maxima. The averaged over ∆t 2 magnitude of R(t) was accepted as an estimate of the maximal value of the flux growth rate, R MAX , which varies in a range of (0.5-5)×10 20 Mx hour -1 for active regions with the maximal total unsigned flux of (0.5-3)×10 22 Mx. The normalized flux growth rate, R N , was defined under an assumption that the saturated total unsigned flux, F MAX , equals unity. Out of 42 ARs in our initial list, 36 event were successfully fitted and they form two subsets (with a small overlap of 8 events): the ARs with a short (<13 hours) interval ∆t 2 and a high (>0.024 hour -1 ) normalized flux emergence rate, R N , form the "rapid" emergence event subset. The second subset consists of "gradual" emergence events and it is characterized by a long (>13 hours) interval ∆t 2 and a low R N (<0.024 hour -1 ). In diagrams of R MAX plotted versus F MAX , the events from different subsets are not overlapped and each subset displays an individual power law. The power law index derived from the entire ensemble of 36 events is 0.69±0.10. The "rapid" emergence is consistent with a "two-step" emergence process of a single twisted flux tube. The "gradual" emergence is possibly related to a consecutive rising of several flux tubes emerging at nearly the same location in the photosphere.

Objective. To analyze the results of the surgical treatment of cataract of different etiology in the children and adolescents at the age under 14 years based at the Cheboksary branch of C.N. Fedorov Eye Microsurgery Complex during the past 10 years. Material and methods. We undertook the retrospective comparative analysis of the results of the surgical intervention for the treatment of cataract in the children and adolescents at the age varying between 3 months and 14 years (390 eyes). The majority of the children presenting with post-traumatic cataract were at the age of 4-6 years. The long-term results of surgery were evaluated in 194 children (253 eyes or 65%) during the 6-36 month follow-up period. The presence of cataract was documented in 209 eyes of the patients with congenital cataract (including 92 ones with unilateral and 58 with bilateral cataract respectively). Post-traumatic cataract was documented in 44 eyes. Facoaspiration combined with the implantation of an intraocular lens and without it was performed in in 242 and 11 eyes respectively. The post-operative complications that developed in 79 children required the secondary surgical treatment. Results. The inflammatory reaction during the post-operative period was apparent in the children given the surgical treatment during the first year of life. The visual acuity in the patients with congenital cataract increased to 0.8-1.0 in 12.3% of the cases, to 0.5-0.7 in 49.2% of the cases, and to 0.2-0.4 in 23.1% of the patients. In the children presenting with post-traumatic cataract, the visual activity increased to 0.8-1.0 in 3.7% of the cases, to 0. 5-0.7 in 14.8 in 14.8% of the cases, and to 0.2-0.4 in 33.3% of the patients with this pathology. Conclusion. The removal of cataract with simultaneous implantation of the intraocular lens into the capsular sac is the highly physiological treatment that improves the conditions for the management of amblyopia and makes it possible to increase the number of eyes with improved visual function after the surgical treatment of this pathology. The application of the small-incision technology allows the occurrence of inflammatory reactions during the post-operative period to be reduced.

Purpose: To analyze changes of functional parame¬ters and aberrations before fitting and after using rigid gas-permeable scleral lenses (RGPSCL) in patients with irregular cornea. Material and methods. 21 patients (29 eyes) with irregular astigmatism of various etiology were enrolled in this study. The patients could not achieve good visual aсuity in glasses, standard soft or rigid corneal contact lenses. Complex ophthalmologic examination was per¬formed: autorefractometry, visometry, biomicroscopy, computer corneal topography, aberrometry on “OPD-Scan II” (“Nidek”, Japan) before fitting scleral lenses and during the period of their wearing. Results and discussion. The results demonstrat¬ed significant visual acuity improvement after RGP¬SCL fitting in all observed patients. UCVA amounted to 0.1±0.18, BCVA in glasses amounted to 0.4±0.26, BCVA in RGPSCL amounted to 0.7±0.1. An increase of best-corrected visual acuity in RGPSCL was statistically significant in patients after keratoplasty, after intra-stromal corneal ring segments (ICRS) implantation, af¬ter refractive laser surgery (RLS) and in cases of mixed astigmatism. We have found that the correction of ker¬atoconus with the use of RGPSCL resulted in a decrease of the root mean square value (RMS), measured in the 3 mm and 5 mm zones by 2.5 times and 4 times, re¬spectively. In patients wearing RGPSCL after kerato¬plasty, statistically significant decrease in RMS was observed in the 3 mm zone (by 3.85 times) and in the 5 mm zone (by 2.99 times). In patients wearing RGPSCL after implantation of intrastromal corneal ring segment (ICRS), RMS in the 3 mm zone decreased by 1.5 times. In patients wearing RGPSCL after refractive laser surgery (RLS) RMS was 2.5 times lower in the 3 mm zone and 2.8 times lower in the 5 mm zone. In case of mixed astigmatism correction with RGPSCL, RMS increased by 1.6 times in the 3 mm zone and practically did not change in the 5 mm zone. Conclusion. The results obtained demonstrated significant visual acuity improvement in all observed patients. The sub-lens-space filled with tear forms a unified “cornea-tear-scleral contact lens” optic system that corrects unevenness of cornea, decreases amount of high-order aberrations (HOA) and provides a clear stable vision.

This article was designed to present the review of the published research concerning the methods for the correction of progressive myopia in the children and adolescents for the purpose of prophylaxis of its further development.

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