Перегляд за автором "Tymkovych, M."
Зараз показано 1 - 15 з 15
Результатів на сторінку
Варіанти сортування
Публікація 3D modeling, errors sources, internal map, optical detection, surgical navigation system(American Scientific Publishers, 2015) Аврунін, О. Г.; Alkhorayef, M.; Saied, H. F. I.; Tymkovych, M.Several causes of spatial errors in surgical navigation system have been investigated for several systems. These include identification error of the external features used for registration, geometrical distortion in the preoperative images, and tracking error of the surgical instruments. Another potentially important source of error is the patient head position detection retrospectively and concurrent with surgery. The visualization of target zone is carried out according to reference landmark points inside the center of the brain as well as an automatic algorithm for contour recognition (based on 3D segmentation and computer morphometry) was applied to edge the contour. Moreover, the optical navigation system was used to assess the accuracy of determination the position of the surgical instrument inside patient head construction using the "internal map" describing the anatomy of the brain. The major sources of errors occurring in the unit of position detection of the optical navigation system were considered. Furthermore, parts of the errors that could appear were simulated while operating the surgical navigation system. Eventually the research included the possibility of using different filters depending on natural source of noise that was also simulated and analyzed.Публікація 3D-reconstruction of anatomical structures using rapid prototyping for medical applications(КрНУ імені Михайла Остроградського, 2016) Аврунін, О. Г.; Avrunin, O. G.; Tymkovych, M.; Filzov, M.3D-reconstruction of anatomical structures using rapid prototyping for medical applications is described.Публікація Advances in cryopreservation of alginate-encapsulated stem cells and analysis of cryopreservation outcome(Інститут проблем кріобіології та кріомедицини НАН України, 2018) Gryshkov, O.; Mutsenko, V.; Tymkovych, M.; Tarusin, D.; Sirotinskaya, V.; Braslavsky, I.; Аврунін, О. Г.; Glasmacher, B.Advances in cryopreservation of alginate-encapsulated stem cells and analysis of cryopreservation outcome is described.Публікація Application of rapid prototyping technology to creation full-scale anatomical models for education of healthcare professionals(НУ "Львівська політехніка", 2016) Аврунін, О. Г.; Avrunin, O. G.; Tymkovych, M.; Shushliapina, N.; Filzov, M.Application of rapid prototyping technology to creation full-scale anatomical models for education of healthcare professionals is described.Публікація Application of SOFA Framework for Physics-Based Simulation of Deformable Human Anatomy of Nasal Cavity(Springer, 2021) Avrunin, O. G.; Tymkovych, M.; Selivanova, K.; Nosova, Ya.Surgical medicine is one of the most radical approaches for the treatment of numerous types of diseases. Recently broad application has taken the direction of computational surgery that aims to improve the quality of treatment through the use of computer tools. The use of computational surgery in rhinoplasty is important due to the fact that the results of the intervention directly affect the geometry of the nasal cavity and, as a consequence, the aerodynamic parameters of the nose. In turn, these parameters determine the functional characteristics of the patient’s nasal cavity. In this paper, we have focused on modeling the deformation of anatomical structures using SOFA framework software library considering tetrahedron finite element modeling (FEM), hexahedron FEM, triangle FEM and mesh spring force fields. The simulation results indicate the high functionality of the SOFA framework for modeling the deformation of the airway in rhinosurgical interventions. These results could further be applied for modeling the deformation of the anatomical structure taking into account the change in the topology of a 3D model to simulate such surgical procedures as a cut.Публікація Automatized technique for three-dimensional reconstruction of cranial implant based on symmetry(2015) Аврунін, О. Г.; Tymkovych, M.; Drauil, J.Currently, reconstruction of cranial implants using tomography study is necessary. The work is dedicated to the automation of the process of cranial implant reconstruction. We propose a set of image processing operations at three-dimensional reconstruction of cranial prosthesis using symmetry.Публікація Capabilities to visualize the operating region of surgical intervention relatively to cranial landmarks for neuronavigation(2016) Аврунін, О. Г.; Tymkovych, M.; Kononenko, T.During the work we analyze the process of neuronavigation in terms of using different approaches for aligning the operational volume at surgical stage in respective to the preplanning data. The work is dedicated to capabilities to visualize the operating region of surgical intervention relatively to cranial landmarks for neuronavigation. We analyzed the principles of selection of anatomical landmarks. We give practical advice on the choice of anatomical landmarks with respect to system of image analysis. Based on processes of image analysis and image processing we show necessity of utilization specialized anatomical landmarks. At this research we propose utilize the cranial landmarks on outer edge of cranium. It was confirmed the possibility of their automated determination. Was shown the necessity of intracerebral landmarks binding to the cranial landmarks. The proposed approach to selection of anatomical landmarks can be applied in neuronavigation for simplification process of their extraction and their calculation.Публікація Classification of CT-brain slices based on local histograms(SPIE, 2015) Аврунін, О. Г.; Tymkovych, M.; Pavlov, S.; Timchik, S.; Kisała, P.; Orakbaev, Y.Neurosurgical intervention is a very complicated process. Modern operating procedures based on data such as CT, MRI, etc. Automated analysis of these data is an important task for researchers. Some modern methods of brain-slice segmentation use additional data to process these images. Classification can be used to obtain this information. To classify the CT images of the brain, we suggest using local histogram and features extracted from them. The paper shows the process of feature extraction and classification CT-slices of the brain. The process of feature extraction is specialized for axial cross-section of the brain. The work can be applied to medical neurosurgical systems.Публікація Computed tomography dataset analysis for stereotaxic neurosurgery navigation(2019) Avrunin, O.; Tymkovych, M.; Semenets, V.; Piatykop, V.Experience of design methods of image-guided navigation for stereotaxis neurosurgery is described. The above approach allows obtaining high accuracy to identify spatial the position of the reference stereotactic landmarks. Visualization of the contours of the third ventricle gives the ability to calculate the center of intracerebral stereotactic coordinates system. Use of the proposed techniques in the clinic allows significantly (up to 20%) to improve the effectiveness of stereotactic operations in parkinsonism. Methods for computer tomography image processing are proposed and analyzed. Further, increase accuracy stereotactic targeting functional surgery is associated with the development of machine analysis algorithms tomographic data with a view maximum recognition automation intracerebral landmarks taking into account their individual variability and allow to improve systems for surgical planning by using virtual and full-scale simulation modeling of the main stages a surgical intervention.Публікація Cryopreservation of stem cells within intact alginate microspheres(IUPESM, Prague, Czech Republic, 2018) Gryshkov, O.; Tymkovych, M.; Аврунін, О. Г.; Glasmacher, B.Cryopreservation processes of stem cells within intact alginate microspheres are described.Публікація Determination of nasal breathing disorders according to computer tomography(IEEE, 2020) Avrunin, O. G.; Nosova, Y.; Tymkovych, M.; Khudaieva, S.; Yurevych, N.; Glasmacher, B.The most important factor that determines the normal functional state of the nasal mucosa is that which passes through it during inhalation and exhalation air flow, which, entering the nasal cavity, due to the active expansion of the chest feels resistance from the surrounding structures. This factor is influenced by an indicator such as air flow resistance, with 54% of the total resistance of the respiratory system to the upper respiratory tract, including 46% of the resistance of the nasal cavity. In addition, it is necessary to study the aerodynamic laws that play an important role in the regulation of the degree of nasal resistance. Nasal resistance can be affected by a variety of external factors and pathological processes in the nasal mucosa: cold air inhalation, hyperventilation, allergy and inflammation, alcohol abuse. Thus, the blood supply in the cavernous venous plexuses promotes swelling of the nasal membranes, an increase in their size, and narrowing of the lumen of the nasal valve to completely block the nasal cavity, causing changes in normal function. Such air flow supports clearly require an objective study to overcome it. Given that the objective assessment of nasal resistance is extremely difficult, it is necessary to create additional diagnostic methods, tools and criteria based on data from a complex of diagnostic measures, such as computed tomography, endoscopy, rhinomanometry.Публікація Ethylene glycol improves cryopreservation of cell-seeded electrospun scaffolds in cryobags(Zalozba FE, 2020) Аврунін, О. Г.; Avrunin, O. G.; Тимкович, М. Ю.; Tymkovych, M.; Glasmacher, B.; Gryshkov, O.Cryopreservation of functional three-dimensional tissue-engineered constructs described. This work suggests that using controlled cryopreservation steps and EG as a non-toxic CPA, efficient cryopreservation of TECs in cryobags becomes feasible.Публікація Image-series analysis for recrystallization process evaluation(ХНУРЕ, 2018) Аврунін, О. Г.; Тимкович, М. Ю.; Tymkovych, M.; Gryshkov, O.; Glasmacher, B.Developed software for analyzing the process of recrystallization by a series of microscopic images. Based on the obtained parameters of recorded crystals, identification and temporary binding of structures in different time intervals are possible. The process of processing a series of microscopic images is considered, the main stages and the arising difficulties at each of them are revealedПублікація Optimal cryopreservation yields intact alginate microspheres and high cell viability after thawing(Інститут проблем кріобіології та кріомедицини НАН України, 2018) Gryshkov, O.; Tymkovych, M.; Rittinghaus, T.; Аврунін, О. Г.; Glasmacher, B.Оптимальные выходы криоконсервации интактные альгинатные микросферы и высокая жизнеспособность клеток после оттаивания описаны.Публікація Tracking of endotelial cells of cryo-micro preparations based on transformation cells.(Hannover, Germany, 2013) Tymkovych, M.; Аврунін, О. Г.; Glasmacher, B.Tracking of endotelial cells of cryo-micro preparations based on transformation cells is described.