Etiosurgery of total post-burn limbal deficiency by allogeneic limb transplantation

Purpose: Analysis of results of allolimbal fragments transportation, conserved by normothermia within 21-28 days, in post-burn corneal leukoma and recurrent pterygiums. Methods: Allolimbal fragments transplantation, conserved by normothermia, was performed in 16 eyes, 6 eyes were with post-burn corneal leukoma, and was combined with penetrating keratoplasty. In 10 eyes with recurrent pterygiums was performed allolimbal transplantation, in which on the limb area within the dissected body of the pterygium were fitted limbal transplants and fixed by interrupted sutures. Limbus allotransplantants conservation was performed in the modified environment DMEM/F12 with glutamine, insulin, dexamethasone, embryonal serum, HEPES and antibiotic-antimycotics composition in terms of CO2-incubator at 37° C, 95% of humidity and 5% of CO2, and for 21-28 days. Results: After keratoplasty in the post-burn corneal leukomas in the early postoperative period the transplantant epithelialization was observed in the epithelial graft for 7-14 days, due to the limbus transplants epithelium. Within 6 months after the surgery, corneal transplants has been remained transparent. After allolimbal transplantation any relapses in patients with recurrent pterygiums was not observed, patients` observation has been currently continuing. Conservation of limbus allotranslantants allows significantly increase the number and activity MSC-like limbus cells and significantly reduce the concentrations of histocompatibility antigens in transplantants, that allows not to use immunosuppressive therapy in the postoperative period. Conclusions: Combined performing of penetrating keratoplasty and allolimbal fragments transplantation, conserved by normothermia within 21-28 days, significantly increases the percent of corneal transparent retention. Allolimbal fragments transplantation, conserved by normothermia within 21-28 days, in recurrent pterygium - pathogenetically reasonable treatment method, which doesn’t require immunosuppressive therapy. Eliminating sectoral limbus deficiency, it creates a barrier to the growth of the conjunctiva

Qualitative analysis of changes in the posterior segment of the eye wich femtosecond laser–assisted cataract surgery

Purpose: Analysis of the qualitative changes in the posterior eye segment structures – choroid thickness (CT) and distance height of vitreous posterior hyaloid membrane (VPHM) from retina by spectral optical coherence tomography (SOCT) method in femtosecond laser–assisted cataract surgery (FLACS). Methods and Materials: 46 eyes with immature cataract and retinal SOCT possibility before the operation. Average corrected visual acuity – 0.3±0.05; eye length - 22.51±0.9 mm; IOP – 20 mm Hg; age - 65 years. Before and after surgery (1, 3, 5 days), SOCT of vitreoretinal interface and choroid was performed, RTVue XR 100 «Avanti», Optovue. Group 1, 24 patients, ultrasound FEM of cataract, «Stellaris», B&L. Group 2, 22 patients – FLACS, LenSx, Alcon. Capsulorhexix diameter – 4.9-5.2 mm (energy 12.5 μJ). Fragmentation of the lens nucleus by «chop», «cylinder» methods (energy 10-15 μJ). The main corneal incision – 2.5 mm (energy 5 μJ). Phakoaspiration on «Stellaris», elastic IOLs were implanted. FLACS duration – 9-10 minutes, femtolaser effect ≤ 2 minutes. Results: Before the surgery CT in Group 1 was 253.1±62.1 microns. In 1, 3, 5 days after FEM of cataract CT were 310.4, 262.7, 258.1 microns. Distance height of VPHM before the surgery was 400.1 microns. In 1, 3, 5 days after surgery – 505.6, 492.7, 500.3 microns. In Group 2 before the surgery CT was 256.4±60.3 microns. In 1, 3, 5 days after FLACS CT were 333.1, 279.4, 259.1 microns. Distance height of VPHM before the surgery – 366.2 microns. In 1, 3, 5 days after FLACS – 510.8, 506.2, 508.9 microns. Reactive thickening of the choroid after surgery was determined in both groups. Group 1, 1th day – 57.3 microns (22.6%). By the 5th day CT became initial. Distance height of VPHM increased by 105.5microns. By the 5th day the situation was not changed. Group 2, FLACS, thickening of CT per 1 day is 76.7 microns, (29.9%). By the 5th day CT returned to previous values. VPHM was increased by 144.6 microns. By the 5th day the situation was not changed. Conclusion: Increase of TC and distance height of VPHM in the early postoperative period was noticed in the both groups. After FLACS big figures are conditioned apparently by intraoperative vacuum effect and/or sudden IOP changes during femtolaser stage. Return of CT to initial state indicates processes reversibility. Patients with vitreomacular adhesion when FLEC are highly risky of vitreomacular traction

Determination of optimum law lift element lining the manipulator of tunnel stacker

Получены новые закономерности подъема элементов обделки манипулятором тоннельного укладчика. Определен оптимальный закон перемещения элементов обделки на заданную высоту.Obtain new regularities of lifting lining elements using the manipulator tun‐nel stacker. The optimal law of displacement elements lining a predetermined height was determined

Terahertz radiation in ophthalmology (review)

Terahertz (THz) radiation is one of the new, intensively studied interdisciplinary fi elds of scientifi c knowledge, including medicine, in the fi rst decades of the 21st century. At the beginning of this article (review), in a brief form, the basic statements on THz radiation, the main parameters and properties are presented; the modern THz biophtonics technologies used in biology and medicine are considered – THz refl ectometry, THz spectroscopy methods. Then a number of directions and examples of possible use of THz technologies in biology and medicine, including pharmaceuticals, are given. The main part of the review presents the progress of experimental research and the prospects for the clinical application of medical technologies of THz spectroscopy, THz imaging, in ophthalmology in the study of the morphological and functional state of the ocular surface structures, diagnosis, medical testing, and treatment of ophthalmopathology of the ocular surface. The article concludes with a review of experimental studies on the safety of using THz waves for medical diagnostics and treatment of ophthalmopathology. In the fi nal part, the main problems and prospects of introducing medical THz technologies into the clinical practice of an ophthalmologist are considered

МОДЕЛЬ ВИЗНАЧЕННЯ ТОПОЛОГІЇ МЕРЕЖІ ЕЛЕКТРОПОСТАЧАННЯ

We propose a model for defining the mains topology based on evaluation of mains improvement by changing the topology in certain areas, as well as the algorithm for determining the mains routing.Предложена модель определения топологии сети на основе использования оценки улучшения варианта схемы при изменении топологии в отдельных зонах, а также алгоритм определения пути прокладки магистрали.Запропоновано модель визначення топології мережі на основі використання оцінки поліпшення варіанту схеми при зміні топології в окремих зонах, а також алгоритм визначення шляху прокладання магістралі

Determination of cutting temperature while milling titanium alloy by face mills

В роботі наведений аналіз особливостей процесу високошвидкісного різання, яке головним чином пов'язують з температурою різання в залежності від швидкості обробки. Разом з ти, показано, що в залежності від конструкції та розмірів інструменту основний критерій зниження температури різання не завжди характеризує високошвидкісну обробку. Причиною цього є підвищення температури до значень, при яких можлива зміна властивостей поверхневого шару оброблюваного матеріалу. З метою визначення температури різання при обробці титанових сплавів, було проведене моделювання процесу торцевого фрезерування методом скінченних елементів дисковою фрезою Ø160. Визначені значення температури на контактних поверхня при швидкостях різання від 80 до 250 м/хв. В даному діапазоні швидкостей обробки спостерігається зростання температури різання. Встановлено, що при швидкостях різання вище 80 м/хв на поверхні оброблюваної заготовки виникають температури, при яких утворюється крихкий шар. Результати моделювання були перевірені експериментально при фрезеруванні титанового сплаву ВТ6.In this article, the analysis process features high-speed cutting, which mainly attributed to the cutting temperatures depending on the speed of processing. Shows that depending on the design and tool size main criterion decrease temperature cutting not always characterized by high-speed processing. The reason for this is the rise temperature to values at which to change properties of the materials surface layer. To determine the cutting temperature of titanium alloys processing, we carried mechanical milling process simulation with mill Ø160 by finite element method. Defined temperature on contact surfaces at cutting speeds between 80 and 250 m/min. In this range of speed observed temperature cutting increase. Established, with cutting speeds higher 80 m/min workpiece surface have temperature at which the fragile layer formed. The simulation results verified experimentally in the milling of titanium alloy VT6.В работе приведен анализ особенностей процесса высокоскоростного резания, которое главным образом связывают с температурой резания в зависимости от скорости резания. Вместе с тем, показано, что в зависимости от конструкции и размеров инструмента основной критерий снижения температуры резания не всегда характеризирует высокоскоростную обработку. Причиной этого есть повышение температуры до значений, при которых возможны изменения свойств поверхностного слоя обрабатываемого материала. С целью определения температуры резания при обработке титанового сплава, было проведено моделирование процесса торцевого фрезерования методом конечных элементом дисковой фрезой Ø160. Определены значения температуры на контактных поверхностях при скоростях резания от 80 до 250 м/мин. В этом диапазоне скоростей обработки наблюдается повышение температуры резания. Установлено, что при скоростях резания выше 80 м/мин на поверхности обрабатываемой заготовки возникают температуры, при которых образуется хрупкий шар. Результаты моделирования были проверены экспериментально при фрезеровании титанового сплава ВТ6

The development of a concept project unloading complex in a сoal terminal in the software SOLIDWORKS

Разработана компьютерная компоновочная модель разгрузочного комплекса. Произведено моделирование движения машин и узлов, соответствующее технологическим процессам протекающим при работе комплекса.A computer layout model of the unloading complex was designed. Motions of machines and units, corresponding to technological process operates when the complex works were simulated

DEVELOPMENT OF AN AUTONOMOUS INTELLIGENCE UNIT FOR A MOBILE NATURAL GAS CONCENTRATION ANALYZER

We have developed an autonomous reconnaissance and return system for a mobile natural gas concentration analyzer for use on offshore platforms in the Arctic

ANALYSIS OF CLINICAL CASES АНТИ-VEGF TREATMENT OF MASSIVE SUBRETINAL HEMORRHAGES COMPLICATING WET AGE-RELATED MACULAR DEGENERATION

Purpose. Analysis of clinical cases of anti-VEGF therapy (ranibizumab) in the treatment of wet age-related macular degeneration (AMD) complicated by massive subretinal hemorrhages of various sizes.Material and methods. A retrospective analysis of the results of treatment was performed in 18 patients with wet AMD complicated by massive subretinal hemorrhages, who received as a treatment three monthly intravitreal ranibizumab injections. The first group (10 eyes) included patients with hemorrhages ranging from 1.5 to 3 disc diameters (DD), the second group (8 eyes) – patients with subretinal hemorrhage area of up to 1.5 DD. The age of patients varied from 65 to 83 years. The study was conducted using visometry, ophthalmoscopy of the damaged eye and of the fellow eye, as well as a monthly photo-registration of fundus and the OCT of macular area. The examinations were carried out before the treatment and 1 month after each ranibizumab IVI conducted by the standard technology in a sterile operating room.Results. After 3 monthly ranibizumab IVI in 8 patients of the second group the ophthalmoscopy showed a complete resorption of subretinal blood already after the 2nd ranibizumab IVI. According to the OCT a normalization of anatomy in the macular area was noted. Visometry results and patients subjectively reported a gradual improvement in visual acuity in the course of treatment, in some cases up to a full recovery by the end of the third month of therapy. A pigment epithelial tear, passing through the foveal zone, was detected in the treatment process associated with resorption of submacular clumps in 9 of 10 patients of the first group with areas of subretinal hemorrhages more than 1.5 DD. A complete attachment and a recovery profile of the foveal zone were not observed in any patients even after the full course of anti-VEGF therapy. A total hemophthalmus developed in one eye in the postinjection period that required the vitrectomy surgery. The visual acuity in patients of the first group decreased from 0.3 to0.15 in the anti-VEGF therapy in the majority of cases. At the same time all patients reported a subjective improvement in the quality of vision – a reduction of the size and intensity of the central scotoma darkening due to a resorption of subretinal blood in the central area of the retina.Conclusion. The therapy with intravitreal injections of ranibizumab is indicated and effective in patients with hemorrhages more than 1.5 DD. anti-VEGF therapy leads to an improvement in the life quality of patients and facilitates their adaptation to a visual impairment, due to a total or partial resorption of subretinal blood and a reduction in the area and intensity of the central scotoma