Overall aim: Fundamental investigation of a whole dual-mode microwave applicator system for diagnosis and thermal treatment of organic tissue that could be used for the first time on human patients

1. Thermal ablation model: Development of a thermal ablation model based on real medical records for predicting the temperature distribution profile in a particular tissue, the shape and the size of its correspondent ablation zone. This model can be used for exploring and planning treatment delivery strategies.

2. Modeling and design: Analysis, modeling and design of the dual-mode microwave applicator. The necessary considerations have to be included, to make the applicator MRI compatible and biocompatible. The maximum dimensions, maximum error in the detection of the relative dielectric profile and the desired ablation zone will be the main targets.

3. Optimization for system configuration: An optimization of the structure of the applicator, the appropriate interface with the measurement equipment and the technological process to realize the demonstrators will be conducted to achieve all the proposed requirements and integrate all parts that comprise a complete applicator system.

4. Microwave characterization: Extensive tests with the applicator system, first with phantoms of organic tissue and second with ex-vivo organic tissue will be carried out in order to prove the concept of the complete system and its target application.

5. System evaluation: A comprehensive evaluation of the performance of the applicator system, from both, the engineer and the medical point of view, will be carried out to ensure the realization of a proper applicator, targeted for real medical environments.

Malignant tumor disease is one of the leading causes for mortality in the human population worldwide. Although there are methods available for diagnosis and treatment of cancer deployed in most health care centers, many treatment techniques are still in development and have to be optimized.

Cancer diagnosis is mostly established at an already advanced stage of disease, where treatment is more difficult or impossible. As for treatment, the current methods still have many risks for the patients. Therefore, there is an essential requirement for new and innovative techniques to diagnose and treat all types of cancer. A feasible and practical approach, that can overcome many of the disadvantages of the current methods, is the use of novel highfrequency instruments to go beyond state of the art techniques to diagnose and treat cancer.

In this project, the aim is a fundamental investigation of a novel dual-mode microwave applicator for diagnosis and thermal ablation treatment of organic tissue. The approach that will be investigated is very different to the state of the art techniques used by commercial or experimental applicators. On one hand, the applicator is designed to fulfill two tasks: First, the relative dielectric analysis of the organic tissue, in order to extract the location of abnormalities such as cancerous tissue. Second, to perform highly localized treatment by means of microwave thermal ablation with the same applicator. On the other hand, the advantages of this concept are numerous. Since the proposed sensor structure is based on a planar topology, it is planned to realize it as an array of elements that can locally characterize the tissue and provide spatial information for a more accurate position of the abnormalities. Additionally, the array feature can provide a more localized ablation, where only one single element of the array will heat the tissue at a time. The novel dualmode microwave applicator will use a significantly smaller input power of up to 10 W only than the current state of the art RF and microwave applicators that use 50 to 200 W. Moreover, it has a higher operating frequency of 12 to 20 GHz that will provide a solution for the impedance matching problem between the applicator and the tissue, since at this frequency, the change is not as significant for the performance of the applicator as for RF and the time needed is much shorter. This has proven to be a major setback for thermal ablation treatments.

An essential feature that will be addressed in this project is the possibility of having the applicator compatible with magnetic resonance imaging (MRI) devices. This will allow a more precise placement of the applicator because of the inherent MR soft tissue contrast. The monitoring and implementation of the thermal ablation procedure will be significantly improved and will increase the clinical acceptance.

2016

C. Reimann, M. Puentes, M. Schüßler, R. Jakoby. “Design and Realization of a Microwave Applicator for Diagnosis and Thermal Ablation Treatment”. 10th German Microwave Conference (GeMiC), Bochum, Germany, 14-16 March 2016.

M. Puentes, C. Reimann, M. Schüßler, R. Jakoby. “Microwave Devices for Theranostic Applications”. 7th International Conference on Metamaterials, Photonic Crystals and Plasmonics, Torremolinos-Malaga, Spain, 25-28 July 2016.

C. Reimann, M. Puentes, M. Schüßler, F. Hübner, B. Bazrafshan, T.J. Vogl, R. Jakoby. “Theranostic Microwave Applicator Suitable for Minimal Invasive Therapy of Malignant Tissue”. 38th International Conference of the IEEE Engineering in Medicine and Biology Society (EMBC), Orlando, Florida, 16-20 August 2016.

C. Reimann, M. Puentes, M. Maasch, F. Hübner, B. Bazrafshan, T.J. Vogl, C. Damm, R. Jakoby. “Planar Microwave Sensor for Theranostic Therapy of Organic Tissue Based on Oval Split Ring Resonators”. Sensors, Vol. 16, Issue 5, 2016

2017

Carolin Reimann, Margarita Puentes, Holger Maune, Babak Bazrafshan, Frank Hübner, Thomas J. Vogl and Rolf Jakoby. “A Cylindrical Shaped Theranostic Applicator for Percutaneous Microwave Ablation”. First IEEE MTT-S International Microwave Bio Conference (IMBIOC), 15-17 May 2017.