Software development for Dr. Sennewald Medizintechnik GmbH

The starting point

The Hamburg-based design firm Held + Team designed the user interface (GUI) for the project on behalf of Dr. Sennewald Medizintechnik. For the technical implementation, it recommends t2informatik as the ideal partner. This recommendation is based both on positive experiences from previous projects and on t2informatik’s proven expertise in delivering sophisticated software solutions.

It became clear from the very first discussions that t2informatik’s working methods are perfectly aligned with the project’s requirements. Whilst Held + Team continues to refine the visual design, t2informatik is responsible for the seamless and efficient implementation of the user interface. The aim: a solution that not only impresses in terms of functionality but also meets the highest standards of design.

Implementation

Throughout the entire project, the collaboration has been characterised by a high level of technical expertise, clear communication and a spirit of partnership.

Porting and reusing the model logic from the C++ prototype

At the start of the collaboration, an initial prototype is developed in C++ using WinUI 3. To optimise performance, we split the application into two separate components: the existing model logic from C++ is retained, whilst the rest of the application is rebuilt.

Reusing the model component is particularly valuable, as the dose calculations are implemented in a C++ library. This decision enables us to quickly deliver an initial functional version of the new application. For the user interface, we opt for Avalonia, a cross-platform open-source UI framework that is particularly well-suited to desktop applications and is continuously being developed.

Architecture for distributed work on the app and model

To enable the parallel development of the application and the model, we split the project into separate GitHub repositories. New model versions can be integrated into the application iteratively as NuGet packages. A shared interface library ensures clearly defined and strictly adhered-to communication between both components.

A particular advantage of this architecture is that a simplified model variant can be implemented in the application even during development. This allows the UI to be developed independently without having to wait for the latest model versions. This approach has proven to be extremely efficient and productive throughout the project.

Integration of C++ code into a .NET environment

The existing C++ library is integrated into the .NET ecosystem via C++/CLI. This technology is primarily used to convert data between environments and forward function calls. The result is a compact .NET-compatible DLL, which is integrated into the application as a NuGet package.

Integration of VTK visualisations into Avalonia

VTK (Visualization Toolkit) is used for the visualisation of medical data such as DICOM images and volumetric data – a widely used technology developed in C++ for the representation of complex scientific and medical data. As the model logic is also written in C++, VTK can be seamlessly integrated.

For the user interface, we use ActiViz.NET from Kitware – a .NET wrapper library for VTK. It provides both an interface to VTK and its own controls for 2D and 3D visualisations. This allows integration to be achieved with minimal effort.

Over the course of the project, an architecture will be developed that enables the creation of complex UI interactions with VTK.

Design and implementation of a Redux-based MVVM architecture

To meet the requirements of complex data structures, we integrate a Redux store for the efficient management of state changes. We use a custom-developed, lightweight Redux variant that has proven to be powerful and reliable in practical use.

The Redux store is tightly integrated into the model layer, whilst the remaining components of the application are structured according to the classic MVVM (Model-View-ViewModel) principle. This architecture ensures a clear separation of the user interface and business logic and provides a clear, maintainable codebase.

CI/CD pipeline and release process

A CI/CD pipeline is set up right at the start of the project to ensure seamless integration and continuous delivery. Whenever a change is made to the main development branch, a new version of the application is automatically built and made available for testing. This ensures that an up-to-date and functional version of the software is available at all times.

In addition, we define a structured release process based on GitFlow. During development, several releases are successfully simulated to optimally prepare for and test the transition from the development phase to market launch.

Agile methodology for an efficient development process

To ensure an efficient and transparent project workflow, we implement a suitable agile methodology. This includes, amongst other things:

• daily stand-up meetings to encourage communication within the team and ensure coordination,
• weekly reviews with live demos to make progress tangible and enable early feedback,
• short iterations in 1-week sprints to deliver working results on a regular basis.

This approach enables steady project progress; it also strengthens mutual trust within the team and boosts the motivation of all those involved.

The sustainable development of the product requires the coaching of internal staff. Our tasks include an introduction to WPF development, practices such as clean code, adherence to architectural standards, and the approach to fault analysis. [C#, .NET, UML]

The result

The result is a powerful, modern and future-proof desktop application that combines high technical requirements with an intuitive user interface. Existing investments in the current C++ logic can be reused in a targeted manner, thereby saving development time and incorporating proven calculation models.

Thanks to the chosen architecture, the user interface, model logic and visualisation work together efficiently. At the same time, the clear separation of components enables the parallel further development of different areas, which significantly accelerates implementation and simplifies it in the long term.

The development processes used, featuring automated builds, structured releases and short iterations, create a high level of transparency and ensure consistently high software quality. New features can be deployed, tested and delivered reliably.

Furthermore, internal expertise is being built up in a targeted manner. Staff are trained in technologies, architectural principles and best development practices, ensuring the sustainable long-term development of the product.

This results not only in a successful software solution, but also in a stable technological foundation for future enhancements and further growth.

Dr. Sennewald Medizintechnik and HyperPlan®

Dr. Sennewald Medizintechnik GmbH is a leading company with over 35 years of experience in hyperthermia and excellent expertise in technologies for regional and local heat therapy for cancer treatment. The company is actively committed to the further development of hyperthermia in order to promote its dissemination and to sustainably improve treatment outcomes for cancer patients.

In collaboration with the US manufacturer Pyrexar Medical, Dr. Sennewald Medizintechnik supports the development and distribution of innovative hyperthermia systems. These medical devices are characterised by a high therapeutic efficacy at a simultaneously minimal risk and are used in oncology clinics and research institutions throughout Europe.

Thanks to close cooperation with the scientific community, the company is making a significant contribution to the further development of hyperthermia. This includes, among other things, the development of special software solutions, the promotion of cost reimbursement and the integration of the method into paediatric oncology. In addition, Dr. Sennewald Medizintechnik is actively involved in phase III clinical trials that demonstrate the effectiveness of hyperthermia.

The HyperPlan® software is a specialised solution for planning and optimising hyperthermia therapy. It enables patient-specific treatment planning based on CT imaging data and helps to precisely control temperature distribution. By simulating different treatment scenarios, users can adjust various parameters and evaluate their effects to develop the best possible therapy for the patient.

Click here for more information about Dr. Sennewald Medizintechnik.