Thanks to the advice of Mr. Andras Lasso, I’ve been able to segment the pericardium of the heart (using the Surface Cut option from Slicer). I’ve then applied a threshold to only select the fatty tissue (HU -150 to -50) and it is corretly identified as green pixels on the attached image.
I’ve also checked that this segmentation was correct looking at the label statistics. However, once I run the radiomics on this segment, I noticed that the first order minimum was -346 and the maximum was 73 (outside the range of my initial threshold).
Is this normal? What could cause this difference?