About the software
ViewDEX is a DICOM compatible software that has been designed especially to facilitate image evaluation studies in medical imaging. The first version of the software was presented in 2004 and since then a continuous development has been ongoing. The goal of the development has been to create a general and easy-to-use tool that can handle different modalities and various kinds of image evaluation studies. For example, ViewDEX can handle standard receiver operating characteristics (ROC) studies, free-response ROC (FROC) studies and visual grading studies, as well as a combination of these. In addition, the software can be used for educational purposes and for benchmarking.
The software is being developed in a joint collaboration between the Sahlgrenska University Hospital and the University of Gothenburg. Today ViewDEX is frequently used both for research and for clinical optimization of medical imaging all over the world and have users from over 40 countries and over 200 citations in scientific publications.
ViewDEX is developed using Java programming environment (Oracle, Java Platform Standard Edition, Java SE 8). The image canvas is designed using Java 2D and Java Advanced Imaging (JAI) graphics and imaging libraries. The software requires no installation and can be run from either the computer hard drive, a USB stick, or an external hard drive.
The configuration of a study is made by editing text files, also known as property files. A separate property file is created for each study. In the property file the unique characteristics of a study can be customized, for example available functionality and the tasks (questions) that the observers need to answer while reviewing the study (with additional answering alternatives). Each reviewer will have an individual login name for the study, which facilitates the possibility to display the cases included in a study in a unique randomized order for each observer. During image review the observers can be allowed to change window settings and use the zoom- and pan- and cine-loop functions. The observers can also perform physical measurements in the images, for example length, area, and mean pixel value. In case a study requires localization of pathology, the observers can make markings in the images and answer questions connected to each marking made. For each study the results from each observer are stored in a log file, which is a simple text file. Data from this file can be transferred to, for example, Microsoft Excel for further analysis.
ViewDEX is freely available for non-commercial use. Please refer to Svalkvist et al. (Radiat. Prot. Dosimetry 2021), Svalkvist et al. (Radiat. Prot. Dosimetry 2016), Håkansson et al. (Radiat. Prot. Dosimetry 2010) och Börjesson et al. (Radiat. Prot. Dosimetry 2005) in publications describing studies that has been performed using ViewDEX (see below for detailed information regarding these four references).
· Magnus Båth (University of Gothenburg)
· Tommy Hagberg (Sahlgrenska University Hospital)
· Angelica Svalkvist (Sahlgrenska University Hospital)
· Sune Svensson (Sahlgrenska University Hospital)
Previous members of the development group: Sara Asplund, Sara Börjesson, Markus Håkansson, Nicklas Johansson and Lars Gunnar Månsson
Acknowledgements: The development group would like to acknowledge the large amount of people that have contributed with valuable input regarding the development of ViewDEX throughout the years.
The development of ViewDEX has been supported by grants from: the Swedish Radiation Safety Authority, the King Gustav V Jubilee Clinic Cancer Research Foundation, the Swedish state under the agreement between the Swedish government and the county councils; the ALF-agreement, the Healthcare Committee Region Västra Götaland, the Commission of the European Communities and the Euratom research and training programme 2014-2018 under grant agreement No755523 (MEDIRAD).
A Svalkvist, S Svensson, T Hagberg and M Båth, "ViewDEX 3.0 – Recent development of a software application facilitating assessment of image quality and observer performance", Radiat. Prot. Dosimetry 195(3-4), 372-377 (2021).
Svalkvist A., Svensson S., Håkansson M., Båth M., Månsson L. G., "ViewDEX: a status report," Radiat. Prot. Dosimetry 169(1-4), 38-45 (2016).
Håkansson M., Svensson S., Zachrisson S., Svalkvist A., Båth M., Månsson L. G., “ViewDEX: an efficient and easy-to-use software for observer performance studies,” Radiat. Prot. Dosimetry 139 (1-3), 42-51 (2010).
Börjesson S., Håkansson M., Båth M., Kheddache S., Svensson S., Tingberg A., Grahn A., Ruschin M., Hemdal B., Mattsson S., Månsson L. G., “A software tool for increased efficiency in observer performance studies in radiology,” Radiat. Prot. Dosimetry 114(1-3), 45-52 (2005).