Diffusion Gradient Direction Sequence description and number of items in sequence.
For some postprocessing algorithms it is important to know about the exact polarity of the diffusion sensitizing gradients applied to acquire the image. As it is not possible to deduce this polarity from the bmatrix values, it is also necessary to allow the optional storage of the diffusion gradient directions sequence in the case of BMatrix.
Identifies the diffusion parameters of this frame. One Item shall be included in this sequence.
Diffusion sensitization factor in sec/mm2. This is the actual b-value for original frames and those derived from frames with the same b-value, or the most representative b-value when derived from images with different b-values.
Required if Frame Type (0008,9007) Value 1 of this frame is ORIGINAL and Diffusion b-matrix Sequence (0018,9601) is not present. May be present otherwise.