2D or 3D?

[Henk-Jan Mutsaerts]

Dear Henk,

Thanks for your explanation. You said: 

"This parameter is only needed for 2D acquisitions as the timing of each slice (and hence quantification) differs. For 3D, this parameter can be ignored or set to a dummy value."

May I know how to generally decide if a series of images forms a 3D-Volume or is just a series of 2D images? I looked a the DICOM tags and could no find an apparent solution.  Thank you again.

Regards

Frank

[Henk-Jan Mutsaerts]

Dear Frank,

This is generally something that you know from the get-go, either because you set up the acquisition yourself or from the exam card from the scanner.

Alternatively, a DICOM tag MRAcquisitionType should contain 2D or 3D, you should also be able to see this inside the ASL4D.json file.

Does this help?

Best, Henk

[jan.honza.petr]

Typically, 2D ASL acquisitions use echo-planar-imaging (EPI) readout. While 3D use GRASE (on Philips and Siemens) or FSE with spiral readout (on GE).

You might be able to spot those on the scanner console.

Jan