V.N. Makarov Dr.Sc. (Phys.-Math.), Professor, Department of Physics and Technology, Moscow Technology University, Moscow E-mail: makarov_vn@bk.ru M.A. Makhov Deputy Director, Company «TECHNOSVET», Moscow E-mail: technosvet@bk.ru V.I. Miroschnik Head of Department, Company «TECHNOSVET», Moscow E-mail: technosvet@bk.ru

The main problem of existing facilities for radiofrequency ablation using monopolar electrodes is insufficient volume of tissue coagu-lation and poor heating the peripheral regions of the tumor. The use of water-cooled and infusion electrodes slightly improves the situation but as the distance from the electrode inserted into the tumor, tissue temperature still drops sharply enough on the outer surface of the tumor in the border area under «norm-pathology» destruction of cells becomes ineffective. Therefore the greatest di-ameter securely destroy the tumor is less than 25 mm. The decision of a substantial increase in the volume of coagulation problems associated with the transition to the use of multi-electrode monopolar or bipolar designs. In this study we carried out comparative studies of unipolar electrode and a single heating system from four electrodes. Studies have shown that the use of the system makes it possible to move the maximum temperature field on 5-10 mm from the center of the tumor with laparoscopic input electrodes and 1520 mm at percutaneous introduction. It becomes possible to reduce thermal load of electrodes and to increase temperature in the zone of ablation and to improve the accuracy of ablation. The use of temperature control system eliminates the cooling of the electrodes. As a result the cost of installation design significantly reduced.

 

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