Dear @horvathd ，
Thank you for your answer. The previous error has been resolved.
My DICOM file is PET-CT data obtained after injecting F-18 isotope drugs into the human body. I want to obtain the dose of deposition at the ROI at this time. When I add USRBIN, the DOSE obtained by running is 0. What is the problem?
thanks
dengtiantian
Dear dengtiantian,
please look at slide 33 from
to correctly set up a radioactive isotope source.
Cheers,
David
Dear @horvathd ，
Thank you for your feedback!
I modified my Isotope source according to the file you provided, added RADDECAY and DCYSCORE, and set them to semi analyze decay mode. After running, I found that the highest dose was not at the ROI. What is the reason for this?
Thank you
Dengtiantian
Dear Dengtiantian,
without the dicom/voxel file and the head.bnn source distribution it isn’t easy to give a definite answer.
You could try to plot the head.bnn file directly and see if the source distribution appropriately aligns with your voxel geometry.
Cheers,
David
Thank your rapidly reply!
There are my voxel.vxl and head.bnn files.
[https://drive.google.com/drive/my-drive]
Thank you
Dengtiantian
Dear Dengtiantian,
I only get to my Google Drive when I go to the link you provided. You may need to use the Share option in Google Drive to create a shareable link.
Cheers.
David
Dear horvathd，
I’m very sorry. Can you see if this link opens?
Thank you
Dengtiantian.
Dear Dengtiantian,
it seems the issue is with your head.bnn file. It contains mostly negative bin values (Hounsfield Units), making it impossible for the sampling routine to work correctly (it always selects the first bin).
Cheers,
David
Dear David，
The head.bnn flie I got by selecting DICOM button, and selecting EXPOTRT to get usrbin flie. If I want to solve this problem, how could I fix it?
A paper states（ DOI: (Use of the FLUKA Monte Carlo code for 3D patient-specific dosimetry on PET-CT and SPECT-CT images - IOPscience)） “Modify the FLUKA routine source.f to import such a list and select voxels at the start of each decay particle so that the frequency of each voxel is proportional to its relative count with respect to the total number of image counts”, can I get the correct dose by modifying the source.f file?
Thank you,
Dengtiantian
Dear Dengtiantian,
you are trying to use the CT images as the source of the isotopes, which seems incorrect. (though I’m not an expert in medical applications).
You should try to convert the SPECT/PET images into a .bnn file to use them as the source.
Cheers,
David
Thank you very much for your advice!
Thank you David for this, presentation, it has helped me figure out some concepts in radiation protection calculations.
