It is known that the reproducibility of radiomic features is influenced by myriad factors, one of which is the size of the segmented volume. We hypothesized that parametric maps calculated with a fixed voxel size could address this issue. To test the hypothesis, we conducted a phantom study and could show that the stability across different volumes of interest sizes is indeed increased with this approach. Furthermore, we believe that factors other than the volume confounding effect are likely mitigated by parametric maps; however, this needs to be investigated in future studies. As a side effect, parametric maps visualize the behavior of the features throughout the entire image. This can help to better understand how radiomics work, especially how features can be influenced by artifacts.
Key points
- Parametric maps provide a method to increase the reproducibility of radiomic features.
- The confounding effect of the variability of volume of interest is reduced by using a fixed voxel size.
- Visualising the features in parametric maps can provide insights into their behaviour.
Authors: Laura J. Jensen, Damon Kim, Thomas Elgeti, Ingo G. Steffen, Lars-Arne Schaafs, Bernd Hamm & Sebastian N. Nagel
