Amide's a Medical Imaging Data Examiner (AMIDE) is a completely free tool for viewing, analysing, and registering volumetric medical imaging data sets. It's been written on top of GTK+ , and runs on any system that supports this toolkit (Linux, Windows, Mac OS X with fink, etc.).
You can use the category filters given on the right sidebar to narrow down your search results.
Ginkgo CADx project started in 2009 with the aim to create an interactive, universal, homogeneous, open-source and cross-platform CADX environment.
Ginkgo is built over a huge amount of advanced technologies providing full abstraction of complex tasks as:
3D Slicer is an open source software platform for medical image informatics, image processing, and three-dimensional visualization. Built over two decades through support from the National Institutes of Health and a worldwide developer community, Slicer brings free, powerful cross-platform processing tools to physicians, researchers, and the general public.