The Company and the Product
Eckert & Ziegler BEBIG
Eckert & Ziegler BEBIG is a global supplier of radiotherapy products and a European leader in the field of brachytherapy. In brachytherapy, an enclosed radioactive source is placed inside or in the immediate vicinity of the area to be irradiated in the body, e.g. in cases of cancer of the cervix, prostate, breast and skin. Eckert & Ziegler BEBIG operates subsidiaries and offices in Germany, Belgium, France, Spain, Great Britain, the USA, India and Brazil. In addition, the company has a worldwide network of distributors and agents to support the international sales and marketing of its product lines. Eckert & Ziegler BEBIG is a young, dynamically growing company with around 145 employees all over the world. With annual sales of around 25 million euros, the company pursues a strategy of continuous market expansion and permanent improvement of its product portfolio in order to optimally support the fight against cancer. The company has been listed on the Euronext stock exchange since 1997.
HDR (High Dose Rate) brachytherapy is performed with an HDR afterloader. With the help of applicators and catheters, the small radiation source from a shielded safe – inside the afterloader – is positioned directly in or next to the tumor. The irradiation is planned with an upstream irradiation planning software. The therapy is often carried out on an outpatient basis. This noticeably increases the patient’s quality of life. Eckert & Ziegler BEBIG manufactures two HDR afterloaders: SagiNova® and MultiSource. The systems are designed for the entire range of HDR brachytherapy applications, including intracavitary, interstitial, intraluminal and intraoperative treatments as well as surface therapy of tumors. Eckert & Ziegler BEBIG offers complete on-site installation of the device, technical service and training for clinical users.
The cooperation between Eckert & Ziegler BEBIG and t2informatik
Challenges and Partners
Developing a medical device with a high proportion of software in a multi-regulated environment is a complex task. The security requirements are high and the architectural decisions to be made are far-reaching. As the number of available employees was limited, it was clear at an early stage that Eckert & Ziegler BEBIG would not be able to successfully complete a project without external support. One of the first tasks was therefore to find suitable partners for various aspects of the project. In a first step, Fraunhofer IESE was won as an external partner for the specification phase. With the help of the IESE team, topics such as requirements specification, context, user and task analysis, software risk analysis, initial architecture consulting and evaluation, usability engineering and the design of the graphical user interface were developed. After the specification phase, it quickly became clear that external support was also required for the implementation: The successful cooperation with t2informatik began.
The Development Process
For the project, we proposed and introduced Scrum as the process model. In the first 6 months we occupied the role of ScumMaster. This part of our assignment included the training of Eckert & Ziegler BEBIG employees, the moderation of the meetings, the introduction and adaptation of the project management software in-STEP BLUE and the use of a taskboard oriented to Kanban. [Scrum, in-STEP BLUE, Taskboard]
Development of a test-driven multi-layer Architecture
The main focus was on the highest possible maintainability and safety of the system. We designed the software architecture of the WPF application according to the MVVM pattern. A clean layer separation and the use of code generators based on T4 templates as well as numerous unit tests ensured that all layers could be tested independently of each other. In addition, the CI Server Jenkins was configured, in particular the build processes were adapted and automated. [WPF, C#, .NET, T4 Templates, MVVM, NUnit, NSubstitute, Jenkins]
Development of the Communication Layer
To increase the maintainability of the system, the connection to the medical device was decoupled by interfaces. A separate implementation was realized as default for the behavior of the medical device based on C#. The extracted interface was used to operate and test the WPF application without a connected medical device. Unit tests were written against the interfaces that had to be met by both the reference implementation in C# and the implementation communicating with the medical device. Using the machine-to-machine protocol OPC UA, the communication to the medical device was realized with the help of a third-party library. As part of the analysis of the communication technology, a generator technology with CSV files and T4 templates was established, whereby the interface between the OPC UA client and the server interface can be completely generated. [OPC-UA, C#, .NET, NUnit]
Data Model and Database Upgrade
The data management of the software was described by an Enterprise Architect model and generated using XMI and T4 templates in entity classes. For this purpose, a migration component was developed with which the database schema including the data could be updated version secure and lossless. [NHibernate, C#, SQL, MS-SQL, Enterprise Architect]
Web Application for Device Management
A web application has been developed that can manage and export common data from the HDR Brachytherapy product family in a variety of ways. [Entity Framework, MS-SQL, C#, ASP.NET MVC]
Automatic Upgrade Mechanism
The system is able to update itself independently via an update package. The WPF application runs in a Windows kiosk mode, making it a self-contained, secure application that can update and restart the system. The resulting application was developed test-driven. It is generically extensible by a component model.
Creation of a PDF-A Generator
All system and customer reports must be generated in PDF-A format. For this purpose, a technology based on iTextSharp with XHTML/CSS, XML serialization of model data and XSL transformations was developed under the responsibility of Eckert & Ziegler BEBIG and extended by t2informatik for new reports. XSL templates make it very easy to create new reports, since common sections from both the XML serializations and the XSL transformations can be reused. [XML, XSLT, iTextSharp, NUnit, C#, .NET]
Execution of System Tests
All functional requirements specified in the functional specification had to be verified by system tests for each release of the product. For this purpose, templates for test protocols were created from the requirements and executed in an integrated system. In the case of extensions and/or changes to the requirements, the test protocols were adapted accordingly. [Requirements Management, Test Management, in-STEP BLUE]
Maintenance and Support
During the pilot phase, internal support staff were supported in difficult error analyses and inquiries from international customers were answered. Today we support Eckert & Ziegler BEBIG in the further care and maintenance of the system. We conduct code reviews, increase performance, migrate individual components and help implement customer requirements. [C#, .NET, B&R Automation, Visual Studio]
Transfer of Knowledge
The sustainable development of the product required coaching of the internal employees. These tasks included the introduction to WPF development, practices such as Clean Code, architecture compliance and the error analysis procedure. [C#, .NET, UML]
The success is based on the many years of experience and high motivation of the t2informatik employees.
“A project of this magnitude has not yet been realized within the company. For us, reliability, competence, flexibility and availability were essential for a successful cooperation. It’s a good thing that we chose t2informatik as our partner.”