Measuring and segmenting volumes using the lasso toolTopic number: 1509386592395

You can create and edit a mask for volume segmentation using the lasso tool.

Prerequisite

The volume segmentation tools are available only when at least one volumetric series with a built volume is present in the current presentation group. This can be achieved, for example, by selecting a MPR hanging protocol, or by switching the render type of one of the given viewports to MPR or 3D.

To measure and segment volumes using the lasso tool
  1. On a CT volume dataset, in the Clinical sidebar, click Volume segmentation. Volume segmentation
  2. To remove bone structures or fragments, click the Bone removal button or Bone fragment removal button. Clicking the button again displays the removed bone structures or fragments.
  3. To create a mask, select Add mask > Lasso.
  4. To draw a contour (lasso), drag the mouse.

    The contour is always closed (the point the actual position is connected with the starting point). When performing a sculpting operation, a volume as well as an area is selected. The drawn contour defines the shape that cuts along the viewing direction.

    • When the mouse is on the first click within the current mask, the tool acts as a "remove lasso tool" and removes the marked area from the current mask. This is also indicated by a scissors within the indicator.

    • When the mouse is on the first click outside the current mask, the tool acts as an "add lasso tool" and adds the marked area to the current mask. This is also indicated by a scissors outside the indicator.

If the lasso tool is selected as an editing tool, the lasso precharge mode is active. The current selected mask will be extended or modified by the lasso action.