ClinicIMPPACT

Problem and Context

For many of the Radio-Frequency Ablations (RFA) performed in the liver, there is still a significant mismatch between expected and truly induced lesion size. This can lead to over-treatment with severe injuries (up to 9% major complications), or under-treatment with tumour recurrence (up to 40%).

There are several individual factors related to inner body structures (e.g. vessel flow, liver tissue properties, tumour type and perfusion, proximity to vessels and liver surface etc.) which substantially affect the size and configuration of the ablated lesion. All these factors are not taken into account in the manufacturer's ablation protocol. It is known that the learning curve for RFA treatment is relatively low and reliable results typically require a thorough training of the IRs in the order of two years. A validated planning and simulation tool could shorten this period but is currently not commercially available.

The proposed RFA planning and support tool is therefore unique as it offers a validated software environment, where IRs can interact during the RFA treatment with the virtual tumour ablation through the extensive use of simulation and visualisation technology.

Radio-Frequency Ablation (RFA) is a percutaneous procedure for cancer treatment, which belongs to the minimally invasive and image-guided techniques. Cancer cells are heated up and destroyed by focusing energy in the RF spectrum through a needle. Thus, needle placement and the right amount of energy play the crucial roles for a therapeutic success. However, there is no standardized practice for needle guidance, which can depend on the equipment, or personal preferences (like 2D/3D Ultrasound (US) or CT-guidance).

A comprehensive, user-friendly planning and simulation application for RFA has to support three phases of the clinical workflow:

(1) Pre-interventional simulation which includes parameter space sampling for uncertainty estimation, prospective prediction of tumor coverage and correlated optimization of treatment cycles and access paths.

(2) Peri-interventional simulation for the confirmation of parameterization in advance of treatment, reacting to unforeseen circumstances and concurrent simulation and treatment for confirming success.

(3) Post-interventional simulation aiding in training and education, examination of outcomes in advance of patient monitoring, and investigating failed treatment. For easy integration into the clinical workflow, the simulation application has to be fast and accurate and run on a standard single high-end PC installed in an interventional setting.

RFA Guardian

One main objective of the project is the development of an integrated, accurate tool for predicting RFA-induced lesions in liver tissue.

Sophisticated multi-disciplinary development, comprising image processing, perfusion measurement, real-time simulation, and visualization, ensures quick and accurate prediction of the RFA therapy.

The resulting application combines a multitude of high-performance, high-accuracy algorithms in a single, integrated environment with high attention to usability in the clinical practice.

Clinical Study

The clinical trial is at the core of the project.
The trial is carried out by four clinical institutions in Germany, Austria, Finland and The Netherlands.

• Patients give consent to participate in the trial
• Each patient is treated following the same RFA protocol
• Patient data are analysed within common processing workflow using the RFA Guardian

The patient data acquired in the study is used to validate the simulated necrosis region and to optimize the model parameters to achieve a better simulation accuracy.
The RFA model is adapted to real-time requirements of the clinical environment and integrated into the clinical workflow.