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Purpose: Laparoscopic radiofrequency ablation is safe, practicable, and combines minimally invasive surgery with the advantages of laparotomy. However, application of the laparoscopic freehand puncture is restricted because of capnoperitoneum and the consequent fixation of the needle on two different points. The use of a laparoscopic ultrasound probe with a canal for puncture can solve this problem and improve precision. However, a stiff needle limits the necessary angulation that is needed to reach right-lateral and cranial liver metastases. Therefore we present a new navigation tool for laparoscopic interventions. Materials and Methods: The US Guide 2000 (Ultra Guide, Tirat Hacarmel, Israel) is an independent navigation system compatible with all ultrasound machines and has six degrees of freedom. After proper evaluation of this system under operating room conditions during transcutaneous radiofrequency ablation, we used this technique in laparoscopic radiofrequency ablation. A special adapter was developed to attach the ultrasound-based navigation system to a laparoscopic ultrasound probe. After calibrating the system with an ultrasound phantom, laparoscopic navigation in a liver organ model was studied. Results: Even in cases of angulation of the ultrasound probe no disturbances of the navigation system could be detected. Anatomic landmarks in the liver could be safely reached. No interaction between the navigation system and the laparoscopic ultrasound probe or operating instruments was observed. Conclusion: Our preliminary results show the feasibility of this technique in laparoscopic radiofrequency ablation. The use of an ultrasound-based laparoscopic inline navigation system offers the possibility of out-of-plane needle placement and could combine the flexibility of freehand puncture with the accuracy of a canal for puncture. This could increase the safety and accuracy of punctures. [ABSTRACT FROM AUTHOR]

Background and Objectives: Hydro-jet technology has long been used to cut various materials, such as metal and wood, in the industrial field. In the medical field, this technology has been applied successfully in selective cutting of the parenchyma of the liver. However, to our knowledge, no data are available on the use of the hydro-jet technique for pneumonectomy. The purpose of this study was to evaluate a new dissection technique in which a high-pressure water stream (hydro-jet) and a new dissection probe for pulmonary resection are used. Methods: Thirty pigs underwent right pneumonectomy. Pigs were randomized to either the conventional or hydro-jet-assisted dissection technique. The feasibility of this technique and the features of surgical dissection were evaluated and compared between the two groups. Results: Pneumonectomy was successful in all animals. The mean operative times were 55 and 65 minutes and the mean volumes of blood loss were 37 and 65 mL for the hydro-jet and conventional dissection techniques, respectively. Complications included vascular injury in 6% and 20% of cases with the hydro-jet and conventional techniques, respectively. The use of hydro-jet for pneumonectomy had clear technical advantages over the conventional dissection. Hydro-jet resulted in a selective dissection of fibrous and connective tissue, preserving blood vessels for later ligation. Therefore, the dissection was performed in a relatively bloodless field. The ease of dissection with the bent-tip dissector represents another advantage. The continuous water flow allows a clear view for the operator. Conclusions: This study shows that hydro-jet dissection represents an excellent alternative to the conventional technique for pulmonary resection. The improved anatomic dissection combined with an almost bloodless operating field secondary to continuous water flow may decrease dissection-related complications. [ABSTRACT FROM AUTHOR]