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A prototype device for biological activation of aqueous solutions is presented. The activation is carried out using non-equilibrium (electrolyte) plasma generated by high-frequency glow discharge in water vapor at atmospheric pressure. The structure and functional features of the device are described. The results of investigation tests are presented, including the ranges of the main electrochemical parameters of activated aqueous solutions. It is shown that the activation of aqueous solutions with glow discharge electrolyte plasma is a low-cost procedure that can be implemented under laboratory or field conditions using a small-size device.

We present results from experimental studies supporting the use of electrolytic glow discharge plasma to destroy renal concretions. The rate of fragmentation of urinary stones was assessed in relation to the power of the plasma discharge and the duration of treatment. The process of plasmakinetic lithotripsy was found to be effective for fragmentation of different types of urinary stone. The results lead to the conclusion that plasmakinetic destruction of renal concretions is a fundamentally novel, effective, and economical method which combines well with technologies using radio-frequency surgery in saline for the treatment of pathological processes in urology.

We present here results obtained using hightech bipolar instruments with an electrosurgical device and a non-linear dynamic feedback system for excision of large tissue blocks. The effectiveness of using bipolar scissors with blades made of nanostructured zirconium dioxide and thermostabilized bipolar forceps was assessed using high amputation of the lower limbs as an example. Significant results were obtained showing that the use of innovatory electrosurgical technologies for transfemoral amputation in patients with terminal-stage peripheral arterial disease increases the typical clinical measures of efficacy by an average of 39%. The results can be taken as the basis for a new method of using electrosurgical technology for high amputations of the lower limbs.

We present here the results of studies of laser-induced shockwave destruction of biological tissues obtained experimentally and by computation. In the experiments, microexplosion dynamics were studied by analysis of acoustic pulses induced by explosion of activated charcoal during laser heating of unbound water. The computational method was based on automodel solution of the Stefan problem using a quasilinear approximation. Good agreement was obtained between computation and experimental data for assessment of the main parameters of acoustic waves arising as a result of thermal explosion of microparticles. Morphological studies and clinical testing of the method provided the evidential aspect of the proposed description of the mechanism of shockwave actions.

We present here the results of studies of the effect of low-temperature plasma on the proliferative activity of cells and the repair functions of the biological tissues in animals and plants. The influences of low-temperature plasma on the viability and proliferative activity of human stem cells are considered. Human stem cells can undergo apoptosis or proliferate, depending on the location of the zone of action and the observation time. Treatment of plants with the low-temperature plasma-activated drug Plazmolit, using dilutions giving a high concentration, was found to suppress growth and development, while low concentrations activated growth. These study results led to the conclusion that there is a single mechanism for the processes whereby low-temperature plasma affects the proliferative activity of cells and the repair functions of biological tissues in animals and plants.

We present here the results obtained during the development of an experimental apparatus for transmyocardial laser revascularization based on an Nd:YAG laser. Use of laser irradiation with a wavelength of 1.44 μm was shown to be effective in producing targeted angiogenesis in transmyocardial laser revascularization in experimental studies using a model of ischemic myocardium. The optimum regimes for pulsed Nd:YAG laser irradiation of the myocardium with thermal tissue damage were established. Morphological changes in the transmyocardial laser channels in pig myocardium were studied. The objective of the experiments was to confirm the efficacy of using this apparatus for transmyocardial laser revascularization with an Nd:YAG laser for the treatment of patients with diffuse lesions to the coronary arteries.

We present here the results of studies of the mechanism of plasma formation and the kinetics of plasma glow discharge required for making electrosurgical instruments with controllable plasma temperature. Numerical data on the energy parameters of the high-frequency current required for stable heating of the plasma glow discharge at atmospheric pressure are presented. Scientifically based technical solutions for creating prototype high-quality electrosurgical instruments with controlled-temperature low-temperature plasma glow discharge are described. The value of using a single technical platform based on a modular design for the main functional elements of high-frequency electrosurgical instruments with biological tissue dissection and coagulation modes based on temperature-controllable plasma glow discharge is assessed.

Results obtained using an erbium laser to produce directed angiogenesis in transmyocardial laser revascularization in experiments using an animal model of chronically ischemic myocardium are presented. An assessment of the efficacy of using the erbium laser to produce targeted angiogenesis is presented. The optimum operating regimes for erbium laser pulse irradiation of the myocardium, taking account of thermal tissue lesions, are identified. Morphological changes are investigated and morphometric analysis in tissues in the area of the transmyocardial laser channels are analyzed in a model of chronic ischemic heart disease (IHD) in dogs. Studies were performed for subsequent development and introduction of the new method into clinical practice in patients with IHD with diffuse coronary artery lesions.

Activation of reducing processes in biological tissues by exposure to pulse-modulated radio-frequency (RF) currents is studied. It is shown that the weak destructive effect of RF currents activates the process of proliferation of healthy cells. A prototype device for dosed exposure to pulse-modulated RF currents based on needle electrodes is described. The results of experimental animal studies and randomized clinical studies using a purpose-designed prototype device for dosed exposure to pulse-modulated RF currents are presented. The clinical efficacy of dosed RF stimulation for treatment of purulent, inflammatory, and purulent-inflammatory processes is shown to be high.

The article describes a new method of treatment of pathological integumentary tissues by controlled shock-wave destruction. The controlled destruction is achieved by micro-explosions of finely dispersed particles applied to the pathological tissue surface and exposed to laser radiation. The method is implemented using laser radiation within the transparency range of biological tissues (0.6-1.1 μm) and a suspension of particles absorbing laser radiation in this range. Thermochemical reaction in the exposure zone leads to release of thermal and mechanical energy and results in destruction of biological tissues precisely in the area of application of the laser absorbing suspension. The mechanism of the shock wave effect combines several factors, including the prevailing acousto-mechanical component leading to radical explosive destruction of the superficial structures of tissues. An important distinctive feature of the method is that it allows the depth of the shock-wave effect to be controlled by varying the radiation intensity. In contrast to the well-known laser-based methods, the method suggested in this work allows the depth of the shock-wave effect to be decreased by increasing the laser radiation intensity.

The article describes an aqueous suspension of activated carbon particles containing unbound water used for treatment of dystrophic gynecological diseases. The treatment is based on the method of controlled shock wave destruction of pathological tissues using laser radiation poorly absorbed by the tissues. A technology for saturating internal micropores of activated carbon particles with unbound water and preparing the aqueous suspension is described. The results of histological in vitro studies of the zone of necrosis caused by exposure of model biological objects (mucous membrane of miniature pig vagina) to shock waves are presented. It is shown that the thickness of the necrosis zone decreases with increasing intensity of laser radiation.

We present here the results of an experimental study of the effects of capture and retention of intrarenal stones in transcutaneous nephrolithotrypsy by irrigation fluid flow and discuss a mathematical model explaining this physical phenomenon. Mathematical modeling and experimental studies were used to formulate the specifications for devices providing increases in stone capture and retention force with a simultaneous reduction in the intrarenal pressure created by the irrigation fluid flow.

This article describes the use of nanostructured zirconium dioxide to provide high performance characteristics for novel electrosurgical instruments. Design solutions providing major functional improvements are described. A clinical study evaluated the effectiveness of using the new electrosurgical instruments with a special high-frequency generator in surgical operations on the thyroid gland.

The article substantiates a new method of treatment of degenerative diseases in gynecology by controlled destruction with laser shock waves poorly absorbed by biological tissues. The shock-wave process is initiated using finely dispersed absorbing particles deposited on the surface of pathological tissues. Absorption of laser radiation by the particles leads to their explosion accompanied by generation of elastic waves. Propagation of these waves in the surface layer of the surrounding biological tissue leads to its destruction. Such destruction can provide a precision therapeutic effect with controlled depth and area.

The results of research into the mechanism of the effect of shock waves on the surface structures of biological tissues are presented. Shock waves were applied to the surface structures to provide their destruction under exposure to laser radiation. The laser radiation parameters were selected so as to reduce its absorption by biological tissues. Fine particles of activated carbon with a high proportion of mesopores filled with unbound water were used to activate the shock-wave decomposition of biological tissues with minimal thermal damage. Particles were deposited on the surface of the biological tissue exposed to laser radiation. The results of histological studies of the shock-wave effect on porcine vulva skin are presented. The results obtained under otherwise identical parameters of laser radiation, but in the absence of a water suspension of fine laser-absorbing particles on the skin surface, are presented for comparison.

The choice of an optimum constructional material for the electrosurgical cutting tools based on nanostructured crystals of partially stabilized zirconia (NPSZe) is substantiated on the basis of criteria of operational stability and functional efficiency. The results of research into adsorption of organic molecules on the surface of the material are used to study the adhesion characteristics of NPSZe. The models of the innovative tools, such as curved bipolar electrosurgical scissors, bipolar forceps, tweezers, and dissectors with nonstick spray, are presented. An experimental model of a high-frequency generator necessary for optimal tool operation is considered.

Specific features of generation of low-temperature plasma in high-frequency plasma discharge electrosurgical apparatuses are discussed for electrolyte solution surrounding a metal electrode. Ignition and stable burning conditions of low-temperature plasma in electrolyte medium at atmospheric pressure are considered. Necessary conditions of plasmochemical electrosurgical action in medicine are discussed. High-frequency electrosurgical apparatuses Plasmatom are presented. The apparatuses operate in low-temperature plasma mode.

Available laser models for transmyocardial laser-induced revascularization (TMLR) are discussed. Laser radiation with λ = 1.44 μm interacts with biological tissue. A 1.44-μm-output solid-state laser based on Nd:AIG has been constructed and tested for medical applications.

The Velmi thermal-laser therapeutic system for treatment of genital human papillomavirus (HPV) infection using photoactivated drug is described. The results of clinical use of this method are discussed. The efficacy of HPV elimination in the uterine cervix was supported by conventional clinical methods of HPV diagnosis (including electron microscopy).

Materials for construction of the cutting parts of surgical tools are considered in this work. The choice of nano-structured crystals of partially stabilized zirconium dioxide (PSZD) as the optimum material for electrosurgical cutting tools is based on criteria of operational stability and functional efficiency. Models of innovative tools are presented including bipolar electrosurgical scissors, bipolar scalpels, and dissector clamps for electro ligaturing. The tools are intended for use with Plasmotom high-frequency electrosurgical devices that generate low-temperature plasma.

High-frequency cold plasma ablation (Coblation) is a non-thermal method of electrosurgery. It is implemented as follows. High-frequency energy is applied to a conductive medium (usually saline solution), causing a highly focused plasma field to form around the energized bipolar electrodes. The plasma field is comprised of highly ionized particles. These ionized particles have sufficient energy (3-6 eV) to break organic molecular bonds within tissue. The byproducts of this non-thermally driven process are elementary molecules and low molecular weight inert gases. Instead of exploding tissue, Coblation causes a low temperature molecular disintegration. The result is volumetric removal of target tissue with minimal necrosis of collateral tissue. Below, the characteristics of the Coblation technology are compared with those of conventional electrosurgery

Development of effective new models of high-frequency electrosurgical instruments is an important problem, although each individual project requires special technological and economic substantiation and marketing prognosis. For example, development of a high-frequency argon jet coagulator was canceled in the Laboratory of Electrosurgical Instruments, All-Russian Scientific-Research Institute for Medical Instrument Engineering (VNIIMP-VITA Joint-Stock Company) at the prototype stage for economic reasons. Indeed, the cost of the newly developed instrument is about 4–5 higher that the cost of the Politom-2, while the efficiency of the argon jet electrode is only 15–20% as higher. Besides, lack of centralized supply of medical institutions with argon significantly reduces the efficiency of the argon jet coagulator.

Results of research into smoldering plasma discharge in electrolyte surrounding a metal electrode with high-frequency pumping are considered. Saline was used as a model of interaction with biological tissue. Kinetic and energy parameters of plasma and charge carriers are estimated. PlasmoTom high-frequency electrosurgical apparatuses with low-temperature plasma generation are discussed.

The above-stated principles and characteristics have been the basis for developing the first domestic high-frequency electrosurgical type Endotom-1 apparatus for endoscopy. Medical tests of apparatus prototypes in the endoscopic departments of the Scientific-Research Institute of Proctology of the Ministry of Health, RSFSR, VONTS Academy of Medical Sciences USSR, and I. M. Sechenov Moscow Medical Institute have demonstrated that the Endotrom-1 apparatus is not inferior to the best foreign models (UES, Acmitom, and others), while with respect to a number of parameters it surpasses them (effectiveness of hemostasis, localization of coagulation, amount of carbon deposit on the electrodes, etc.). The Endotom-1 apparatus has been recommended for serial production by a resolution of the Commission on New Medical Technology of the Ministry of Health of the USSR in 1987.

1. The improved coagulation and accentuated blood clotting in tissue coagulation are produced by high-amplitude voltage pulses, which break cell membranes.