EllipticalRoi Tool
How to set up the EllipticalRoi tool:
// Init cornerstone tools
cornerstoneTools.init();
// Enable any elements, and display images
// ...
// Add our tool, and set it's mode
const EllipticalRoiTool = cornerstoneTools.EllipticalRoiTool;
cornerstoneTools.addTool(EllipticalRoiTool)
cornerstoneTools.setToolActive('EllipticalRoi', { mouseButtonMask: 1 })