Vol 53, No 2 (2019)

This study continues our systematic exploration of the design of an axial circulatory assist blood pump with a rotor on magnetic bearings. The work reported here addresses experimental validation of a numerical model of flow in the flow part of the axial blood pump. The study focuses on design of the test rig, design of experiments, and modeling of blood flow in the flow part of the pump using computational fluid dynamics. The working fluid was distilled water. The flow-pressure characteristics obtained experimentally were compared with those from mathematical modeling. A satisfactory agreement between the results was obtained, such that the mathematical model can be used for future simulation of the operation of the pump and further optimization of the main components.

The effect of a hyperpolarization pulse on a model of cardiomyocyte under simulated fibrillation conditions was studied.

The design of a device for stopping bleeding is considered, in which the operative element is a thermoelectric battery (TEB) operating in cooling mode until the moment at which bleeding stops and in heating mode when the device is removed from the damage site. A model of the device based on solving the problem of thermal conductivity on phase transition is proposed. Numerical experimental results yielded a relationship between the time taken to form solid-phase blood 3 mm thick and the power and supply current of the TEB at different blood flow pressures in the wound zone. The device can use a standard TEB with power consumption of 40_80 W depending on the area of blood flow for procedures lasting 7-8 min.

This article proposes a new use of the Hilbert−Huang transform (HHT) in the preliminary processing and analysis of EEG signals. EEG signal recordings are analyzed using HHT to study patterns of changes in patients with mental disorders. Variants of EEG signals in different coordinate systems are analyzed. Results from analysis of EEG signals demonstrated a relationship between the amplitude−time parameters of HHT and the presence of mental disorders in patients.

This article addresses a novel technical solution in the surgical treatment of intradural spinal cord tumors – the use of intraoperative multispiral computerized tomography (IMSCT). The IMSCT method, as compared with pre-operative magnetic resonance tomograms, provides clear determination of tumor position levels and provides for minimization of the volumes of soft tissue dissection and bone resection, thus reducing the risk of various adverse events. This intraoperative navigation method can be recommended for use in the surgical treatment of intradural spinal cord tumors (IDSCT).

A new method for determining the anode voltage and the total filtration of X-ray diagnostic devices from the profile of secondary radiation fields is proposed. Secondary radiation fields are excited near a composite scattering body made of materials with different absorption properties. It is shown that the asymmetry coefficient and the lower quartile of the experimentally recorded distributions can be used as measurement criteria.

The design and functional capabilities of the portable device for laser-and-ultrasound therapy BINOM®-FIZIO LUZT are described together with the experience of its use for treating patients with chronic obstructive lung disease (COLD). Infrared laser pulses and ultrasound generated by an array of sources are the therapeutic agents used for treatment. The developed device makes it possible to implement a new physical therapy technique for simultaneous (concomitant) treatment with low-intensity laser radiation and ultrasound. Clinical tests showed the device to be cost-effective and improve the clinical effect of combination treatment. It allows better expectoration, peripheral blood parameters, and respiratory function to be achieved.

A method of surgical treatment of midshaft clavicular fractures and a compression interlocking nail for osteosyn-thesis of the clavicle were developed. Strength characteristics of various bone−implant−bone systems in osteosyn-thesis of midshaft clavicular fractures were compared. It was shown that none of the tested fixation techniques provides stability under conditions of axial loading comparable to that of an intact clavicle. The developed design can be recommended as a method of choice for osteosyn-thesis of midshaft clavicular fractures, as it demonstrated strength characteristics comparable to those of other systems.

Hardware and software for surgical instrument navigation using stereo X-ray imaging were developed. The developed surgical stereo X-ray navigation system provides 3D imaging in the process of surgery or during diagnostic examination of deep-lying abnormal foci or structural abnormalities of organs and tissues. Application of the developed system makes it possible to reduce considerably the duration of surgery. The obtained 3D X-ray images are automatically processed to provide accurate real-time guidance of the medical instrument (i.e., adjustment of the penetration depth, position, and orientation of the instrument). The developed technique of stereo X-ray navigation can be used for purposes of upgrading medical X-ray equipment, such as C-arch (Arcoscope) surgical X-ray devices.