Support for more descriptive fields in the image and/or reconstruction parameter files.

[smanwell]

I am in the process of developing a utility that can generate a DICOM version of an interfile image following SPECT reconstruction. All of the DICOM read/write operations are handled via GDCM API made available when STIR is built with links to ITK. The main requirement (other than making sure the image data are inserted correctly) is to populate the DICOM header as completely as possible. The inputs for this utility are:

1. Projection Data (DICOM)
2. Image Data (Interfile), and
3. Reconstruction Parameter file (Interfile)

The DICOM header for the output image is populated based on information included in all of the input files. Much of the original DICOM attributes from the projection data can be copied directly, but other information is associated with the reconstructed image (e.g. pixel spacing, pixel depth, etc...) or parameters of the reconstruction (num iterations, corrections to the data that were performed before/during/after the reconstruction). Some of this information is already included in the input files that I've mentioned, but not surprisingly, there are various common DICOM attributes that do not have analogues in interfile objects. I've listed some examples below.

Unsupported DICOM Attributes (suggested file association):

• Series Description (Recon Par file/Image file/both)
• Image ID (Recon Par file/Image file/both)
• Scatter correction indication (Boolean/type) (Recon Par file)
• Date/Time of reconstruction, i.e. Content Date/Time (Image File)

I am interested in opening this discussion to see if the interfile headers for the image and/or parameter file could be modified to include additional (optional) information to support my endeavour. And if modifications are possible, in which file would they be best insert. I've made suggestions below regarding the file association with each attribute to get the conversation started.

I am also interested in hearing if anyone has experience adding new keywords that get parsed from the interfile files and how they achieved this.