Cannot Find Slab Thickness in .JSON or DiCom - Perfusion Pulsed (ASL)


I was looking through my dicom header for the dicom tag for slab thickness (0018,9104) and I cannot find it. I also cannot find slab thickness in the .JSON. Are there any solutions or ways I can find slab thickness if it is not in either the dicom info or the .JSON?

This question is underspecified. You need to provide details on the manufacturer (e.g. Siemens or Philips), scanner software (e.g. XA or VE) and sequence (e.g. Oxford pCASL). For Siemens V-series scanners, this information is in the CSA header, but location varies by sequence. If you use dcm2niix, it will attempt to identify this information where possible. Note that the Philips DICOM images contain very little sequence information.

My apologies. So it is a Siemens 3T Prisma MRIA with a NOVA 32-channel head coil and the utilization of Syngo MRI software. dcm2niix was already run with this data. I can attempt to find this info in the CSA header.

Make sure you are using the latest version of dcm2niix as we continue to expand our knowledge of the proprietary Siemens CSA header. I have acquired sample ASL DICOMs with six different ASL sequences: PASL2D, PASL3D, pCASL2D, pCASL3D, pCASL2Dve, pCASL3Dve. Which of these are you using, or are you using an entirely different ASL sequence?

For these I provide the Siemens protocol PDF as well as the dcm2niix converted JSON which attempts to extract as much data as possible. You may also want to look at my comments on osf. In my experience, the research pCASL sequences are superior to the Siemens product PASL.

Perhaps you can included one of the JSONs created by dcm2niix. The Prisma can run V* (e.g. VE11) and X* (e.g. XA30) software. The DICOMs are completely different between these. If you use V* you will probably save your EPI images as classic DICOM mosaics. If you use X* you must never save mosaics, as these strip out protocol information. Likewise, X* compatibility mode classic DICOM has quirks. For X*, you really want to save enhanced DICOMs.

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 I know the latest version of dcm2niix was used, I found that in the .json file. From the sequence info, I know it is labeled as "SiemensSeq_tgse_pasl" and series description is labeled as "asl_3d_tra_iso_3.0_highres". I tried to look further for how to find Labeling slab thickness and Use of QUIPSS pulses and their timing in both .json and dicom header. I used dicom_hdr to look for the tag for slab thickness (0018,9104) which does not exist the source data dicom header. As far as "Use of QUIPSS pulses and their timing", I cannot find this one at all in either the .json or the dicom header.


How would I find out from the dicom header tags or .json if  QUIPSS pulses were collected and their timing?