How to set a ROI in a CT image to include pixels within a tumor with CT values over certain threshold?

Hi there,

I wonder if anyone knows how to use imagej to set a ROI in a CT image to include pixels within a tumor with CT values over certain threshold.

Please advise.

Thanks.

Lucas

I am not sure which plugin it is, but if you use Fiji instead of plain ImageJ, there is an option to create a selection from a mask. You could create the mask using thresholding and then create your selection from that mask.

Thank you for your kind reply. Fiji is new to me. But I will try it out.