A simple circle with a given radius


My issue is the following. I need to be able to create a circle (2D) of a specific radius and place it over a certain region of my MRI image. Ideally I should be able to move this circle with my mouse after creation, but it is also okay if instead I have to pre-define where its center is.
Is ther any way to do this in slicer? Or if not, is it possible to create a circle in another software and import it into Slicer, but importantly - still being able to place it where I need it to be?

Thank you!

You can do that with the Shape::Ring object in ‘Projection’ mode, it’s available in the ‘ExtraMarkups’ extension. A ‘Radius’ line is forcibly drawn altogether. If you want to set a determined radius, a few lines of Python code will do that.