3D mode ROI (volume rendering)

In MPR, I implemented the ROI extraction function using the vtkContourWidget widget.

But when I use vtkContourWidget in 3D mode (volume rendering), it doesn’t display well.

I want to draw a closed circle on the screen in 3D mode. How can I achieve this?

Is there a dedicated widget in VTK?

PS:I used the C# version of VTK. Cannot modify source code