NE Scientific (NES) develops a line software products for the guidance of percutaneous RF and Microwave thermal ablation. The software supports physicians in the treatment of liver, lung, and kidney cancer. Physicians typically conduct these procedures under CT guidance, where they can see the position of the ablation probe in the tissues, the tumor, but it might hard for them to appreciate from CT images which part of the tumor has been treated and which part still needs treatment at different stages of the procedure. As a consequence, for medium tumors of the size of 3cm to 5cm, it is estimated that approximately in 24% of cases the tumor is not completely treated, a situation that leads to tumor recurrence.

NES is addressing this problem by simulating in real-time the physics taking place during the procedure, and by highlighting on intraoperative CT images which part of the tumor has been treated and which part still requires treatment, based on the simulations. Under sponsorship of an SBIR grant from the National Cancer Institute, NES has developed a guidance software supporting percutaneous RF ablation which is undergoing a clinical trial at the Dartmouth Hickock Medical Center. The trial started on December 6th 2019 and it is ongoing. In this study the software is used to support the physician in the treatment of liver cancer. The planned enrollment for the study is 52 patients; 16 patients have been recruited to date under IRB approval and informed consent.

Screenshot of ablation guidance software

The guidance software highlights on intraoperative CT images which tissues are necrotized during a first ablation.

The image above shows a screenshot of the software being used on a patient part of the ongoing trial. The tumor is indicated in purple color and its outline is generated by an initial manual segmentation of a contrast CT image. The software automatically generates margins (highlighted in yellow). Margins are additional tissues around the tumor that the physician needs to necrotize in order to ensure that micro-infiltrations of the tumor into nearby healthy tissues are treated as well. In the picture above, the guidance software highlights in green the tissues treated during a first ablation. The physician can easily appreciate from the visualized information how a certain portion of the tumor and margins needs still to be treated – he/she can therefore proceed to repositioning the probe and conduct further ablations to treat the tumor completely. The image below shows a later stage in the procedure, where the physician has practiced five ablations.

Screenshot of ablation guidance software

The guidance software highlights on intraoperative CT images which tissues are necrotized during after multiple ablations.

The application highlights in green color all the tissues that have been treated as a result of the multiple ablations. As it is possible to appreciate from the visualization provided by the software, most of the target tissues (tumor + margins) have been necrotized, and a further ablation will allow the physician to treat small portions of target tissues sill left to be treated. The goal of the software is to ensure through these visualizations that no untreated tissues are left behind; the ongoing trial is designed to assess whether this goal is met in practice.

The indication of which tissues are ablated is based on simulating in real-time the physics of the ablation, computing the tissues temperatures at the ablation site, and on using models of cell death in order to determine which tissues are necrotized. The ability of simulating the in real-time the physics of the ablation is an enabling factor which was demonstrated by NES for the first time (world-wide) in 2014 [1]. To the best of our knowledge, we are also the first organization to enter a clinical trial where this technology (simulation in real-time of ablation physics) is used to support clinical procedures.

The ablation guidance software shown in the above pictures is an investigational device at this time, and will not be available commercially until market approvals have been received by the competent regulatory bodies.

REFERENCES

[1] Borsic, A., Hoffer, E., & Attardo, E. A. (2014) – GPU-Accelerated real time simulation of Radio Frequency Ablation thermal dose. In 2014 40th Annual Northeast Bioengineering Conference (NEBEC) (pp. 1-2). IEEE.