Medical equipment, due to its specificity, requires precise adjustment and testing. Therefore, before direct exposure to a human organism, the equipment is tested on specialized mock-ups of human  tissue – phantoms. The physicochemical characteristics of phantoms should be close to the characteristics of the selected biological tissue. Depending on the task at hand, the design of the phantom itself and its properties will be different. The aim of this work is to create a phantom that clearly demonstrates the distribution of the thermal field in the volume during heating while maintaining the heating pattern for several hours. The studies were carried out on an experimental stand, which contained a device for radio frequency ablation of tissues “METATOM-3” with a set of electrodes, a thermal imager, and a tripod for fixing the electrodes. Animal tissue (pig liver) and plant tissue (potatoes) were used as biological tissue simulators. The most suitable imitator turned out to be potatoes, because the electrophysical parameters of potatoes are close to those of the human parenchymal organs. Thermal exposure of potatoes at 58–62°C leads to changes in the starch characteristics: the appearance of a fine-crystalline structure filled with water from the surrounding space is observed. As a result, volumetric changes in the structure of plant tissue appear at the place of heating, which makes it possible to evaluate the results of thermal exposure. To form a clearer thermogram, part of the potato is cut off. In general, potatoes have a narrow temperature range of reaction in the range of 58–62°C, which conveniently coincides with the temperature of cell death (60°C). The experiments carried out show the effectiveness of such a phantom. The obtained pictures of thermal  field are reliable and persist for several hours. Experimental studies of various singleelectrode and multi-electrode systems provide ground for recommending this phantom for the practice of developing radio-frequency and microwave ablation systems.

Surgical resection remains the most effective treatment for liver tumors but it can still be limited by blood loss which can affect postoperative recovery and long-term survival. New approach towards achieving bloodless resection is the use of heat coagulative necrosis in healthy liver tissue, creating a zone of necrosis with help of monopolar or bipolar linear array of needle electrodes which are connecting with radio frequency generator. Resection of liver can be performed by usual scalpel.Unfortunately appreciable hemorrhages are possible after excising part of tissue because of incomplete coagulation.To solve problem new electrodes system of monopolar linear array of electrode needles with special flat scalpel has been designed Comparison of efficiency of known and offered devices was spent at resection of liver of the big not purebred dogs in department of surgery FMBC of A.I. Bumazj ana.The bloodless volume at use of the offered device has appeared on the average on 30 % less, than at use of the known device.

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The design of a new radio-frequency scalpel is developed for a resection of the parenchymatous organs allowing considerably to improve uniformity of coagulation of a tissue and to reduce time of carrying out of operation.

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