Navigated laparoscopic microwave ablation of tumour mimics in pig livers: a randomized ex-vivo experimental trial

Abstract

Background In order to efficiently perform laparoscopic microwave ablation of liver tumours precise positioning of the ablation probe is mandatory. This study evaluates the precision and ablation accuracy using the innovative laparoscopic stereotactic navigation system CAS-One-SPOT in comparison to 2d ultrasound guided laparoscopic ablation procedures. Methods In a pig liver ablation model four surgeons, experienced (n = 2) and inexperienced (n = 2) in laparoscopic ablation procedures, were randomized for 2d ultrasound guided laparoscopic or stereotactic navigated laparoscopic ablation procedures. Each surgeon performed a total of 20 ablations. Total attempts of needle placements, time from tumor localization till beginning of ablation and ablation accuracy were analyzed. Results The use of the laparoscopic stereotactic navigation system led to a significant reduction in total attempts of needle placement. The experienced group of surgeons reduced the mean number of attempts from 2.75 ± 2.291 in the 2d ultrasound guided ablation group to 1.45 ± 1.191 (p = 0.0302) attempts in the stereotactic navigation group. Comparable results could be observed in the inexperienced group with a reduction of 2.5 ± 1.50 to 1.15 ± 0.489 (p = 0.0005). This was accompanied by a significant time saving from 101.3 ± 112.1 s to 48.75 ± 27.76 s (p = 0.0491) in the experienced and 165.5 ± 98.9 s to 66.75 ± 21.96 s (p < 0.0001) in the inexperienced surgeon group. The accuracy of the ablation process was hereby not impaired as postinterventional sectioning of the ablation zone revealed. Conclusion The use of a stereotactic navigation system for laparoscopic microwave ablation procedures of liver tumors significantly reduces the attempts and time of predicted correct needle placement for novices and experienced surgeons without impairing the accuracy of the ablation procedure.

A narrative review on endopancreatic interventions: an innovative access to the pancreas

“…However, this approach requires a tracking modality that does not suffer from the line-of-sight problem to track the endoscopes flexible tip. The use of electromagnetic tracking can be seen as an alternative to conventional optical tracking and was previously described in preclinical studies for laparoscopic ultrasound-guided ablation of hepatic tumors [66,67] . It is likely that with the improvement of IG surgery, not only the quality of the diagnosis can be improved, but also the safety of the intervention.…”

“…The use of electromagnetic tracking can be seen as an alternative to conventional optical tracking and was previously described in preclinical studies for laparoscopic ultrasound-guided ablation of hepatic tumors. [66,67] It is likely that with the improvement of IG surgery, not only the quality of the diagnosis can be improved, but also the safety of the intervention. In the future, a steep further technical progress can be expected, that brings novel and improved concepts of image guidance to endopancreatic interventions, making the use of this access more accurate, more intuitive and therefore safer.…”