When performing a conversion with nm_mrac2mu an inpainted high-density region in the umap does not get correctly translated.
An inpainted region with value 5000 (1e4/cm) get converted to 0.0904 (1/cm) after using nm_mrac2mu (v2.0.1).
Steps to reproduce the error:
Use a siemens biograph mMR 4-class umap as a basis. Paint in a high-density region and rewrite the dicom files like the original umap dicom series, but with the now modified pixel arrays. Convert the dicom folder to interfile using nm_mrac2mu.
Suggested solution:
Change conversion to allow for larger values or throw a warning if max value in input umap exceeds the maximum supported value of the conversion tool.
Optional: Why high LAC values can be useful?
I use a umap with an inpainted high-density region painted into a region that I can recognize both in the reconstructed PET and the umap itself to verify the alignment of the umap and PET data during image reconstruction.
When performing a conversion with nm_mrac2mu an inpainted high-density region in the umap does not get correctly translated. An inpainted region with value 5000 (1e4/cm) get converted to 0.0904 (1/cm) after using nm_mrac2mu (v2.0.1).
Steps to reproduce the error: Use a siemens biograph mMR 4-class umap as a basis. Paint in a high-density region and rewrite the dicom files like the original umap dicom series, but with the now modified pixel arrays. Convert the dicom folder to interfile using nm_mrac2mu.
Suggested solution: Change conversion to allow for larger values or throw a warning if max value in input umap exceeds the maximum supported value of the conversion tool.
Optional: Why high LAC values can be useful? I use a umap with an inpainted high-density region painted into a region that I can recognize both in the reconstructed PET and the umap itself to verify the alignment of the umap and PET data during image reconstruction.