this study is aimed at the comparison of the process of manual and robotic positioning of the electrode performing radiofrequency ablation under the control of a surgical navigation system. the main hypothesis of this experiment was that the use of a collaborative manipulator (KUKA iiwa) will allow to position the active part of the electrode relative to the center of the tumor more accurately and from the first attempt. We also monitor the stability of the electrode′s velocity during insertion and consider some advantages in ergonomics using the robotic manipulator. We use three more criteria to compare the surgeon's and robotic performance, unlike other studies, where only the target point's accuracy criterion is observed. the main idea is to examine the movement parameters of the electrode that can lead to potential patient trauma. Sphere-shaped tumor phantoms measuring 8 mm in diameter were filled with contrast and inserted in bovine livers. 10 livers were used for the robotic experiment and an equal quantity for manual surgery. the livers were encased in silicone phantoms designed to imitate the liver position in a real patient's abdominal cavity. Analysis of CT data gave the opportunity to find the entry and the target point for each tumor phantom. this data was loaded into a surgical navigation system that was used to track and record the position of the Rf-electrode during the operation for further analysis. the standard deviation of points from the programmed linear trajectory totaled in the average 0.3 mm for the robotic experiment and 2.33 mm for the manual operation with a maximum deviation of 0.55 mm and 7.99 mm respectively. Standard deviation from the target point was 2.69 mm for the collaborative method and 2.49 mm for the manual method. The average velocity was 2.97 mm/s for the manipulator and 3.12 mm/s for the manual method, but the standard deviation of the velocity relative to the value of the average velocity was 0.66 mm/s and 3.05 mm/s respectively. Thus, in two criteria out of three, the manipulator is superior to the surgeon, and equality is established in one. Surgeons also noticed advantages in ergonomics performing the procedure using the manipulator. this experiment was produced as part of the work on the developing of a robotic multifunctional surgical complex. We can confirm the potential advantages of using collaborative robotic manipulators for minimally invasive surgery in case of practice for cancer treatment. Minimally invasive surgery is becoming a standard in the treatment of cancer of internal organs 1-6. The main advantages are considered to be short hospitalization periods and a reduction in the postoperative recovery time. Modern studies also show that there are groups of patients at particular risk (diabetic, with an increased body

This study aims to compare the tracking algorithms provided by the OpenCV library to use on ultrasound video. Despite the widespread application of this computer vision library, few works describe the attempts to use it to track the movement of liver tumors on ultrasound video. Movements of the neoplasms caused by the patient`s breath interfere with the positioning of the instruments during the process of biopsy and radio-frequency ablation. The main hypothesis of the experiment was that tracking neoplasms and correcting the position of the manipulator in case of using robotic-assisted surgery will allow positioning the instruments more precisely. Another goal of the experiment was to check if it is possible to ensure real-time tracking with at least 25 processed frames per second for standard definition video. OpenCV version 4.5.0 was used with 7 tracking algorithms from the extra modules package. They are: Boosting, CSRT, KCF, MedianFlow, MIL, MOSSE, TLD. More than 5600 frames of standard definition were processed during the experiment. Analysis of the results shows that two algorithms—CSRT and KCF—could solve the problem of tumor tracking. They lead the test with 70% and more of Intersection over Union and more than 85% successful searches. They could also be used in real-time processing with an average processing speed of up to frames per second in CSRT and 100 + frames per second for KCF. Tracking results reach the average deviation between centers of neoplasms to 2 mm and maximum deviation less than 5 mm. This experiment also shows that no frames made CSRT and KCF algorithms fail simultaneously. So, the hypothesis for future work is combining these algorithms to work together, with one of them—CSRT—as support for the KCF tracker on the rarely failed frames.

Aim. To assess overall survival and recurrence-free period in patients with locally advanced pancreatic cancer who underwent irreversible electroporation of the tumor in combination with chemotherapy. Matherials and methods. It was performed a prospective analysis of overall survival in 23 patients who underwent irreversible electroporation of unresectable pancreatic cancer for the period from May 2012 to March 2017. Control group consisted of 35 patients with pancreatic cancer stage III who received standard chemotherapy alone. Results. Mean age of patients was 61 years (range 45–80). All procedures were successful. Fifteen patients had pancreatic head cancer, 8 – cancer of pancreatic body. Preoperative chemotherapy has been applied in 20 (86.9%) patients for 4 months prior to surgery on the average. Seventeen (73%) patients underwent chemotherapy after electroporation procedure. 90-day mortality was 4.3% (n = 1) in electroporation group. Surgery was followed by improved local recurrence-free survival (12 and 6 months, respectively, p = 0.01) and distant recurrence-free survival (15 and 8 months, respectively, p = 0.03). Overall survival was 18 and 11 months, respectively (p = 0.03). Conclusion. Irreversible electroporation of locally advanced pancreatic cancer is safe. Four-month chemotherapy followed by surgical procedure is associated with good local response and better overall survival compared with chemotherapy alone. These data will be validated in further multicenter study.

The OBJECTIVE of this work was to study the possibility of preoperative color 3D-modeling and intraoperative navigation through the use of the system «Avtoplan» in the surgical treatment of patients with pathology of the liver.MATERIAL AND METHODS. System «Avtoplan» was used in 32 patients with different surgical diseases of the liver: hemangioma, hydatid cyst, alveococcosis and metastatic colorectal cancer to assess the feasibility of the operation – resection of the liver of a particular volume.RESULTS. The performed 3D-modeling of the liver in the preoperative stage were used in 3 cases (10.3%) of 32 to abandon the planned surgical treatment in favor of conservative therapy due to local spread of the pathological process (in 2 cases – metastatic bilobate and in 1 case – alveococcosis organ damage). Of the 29 operated patients, in 6 (20.7%) at the stage of preoperative modeling, the planned volume of liver resection was changed: in 4 patients, in the direction of its increase in connection with the identified topographic and anatomic location of tumors, and in 2 patients, in the direction of its reduction due to the peculiarities of the blood supply to the zone of surgical interest.CONCLUSION. Preoperative 3D-modeling allowed the surgeon to better prepare for surgical intervention according to individual anatomical characteristics of the patient and to choose the optimal extent of surgery. Knowledge of 3D topography of liver lesions allowed reducing intraoperative blood loss and the likelihood of damage to intrahepatic structures (vessels, bile ducts). Postoperative 3D modeling allowed to assess the adequacy of the volume of surgery performed and could serve as an objective criterion in assessing the quality of medical care.The authors declare no conflict of interest.The authors confirm that they respect the rights of the people participated in the study, including obtaining informed consent when it is necessary, and the rules of treatment of animals when they are used in the study. Author Guidelines contains the detailed information.

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