Digital Imaging and Communications in Medicine (DICOM)

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Chapter 7 DICOM SOPs: Basic
Procedure Step Sequence” element is encoded here with SQ VR (see 5.3.10);
that is, it includes a subsequence of items (0040,0001), (0040,0002), and more.
This sequence encapsulates the schedule for the patient scan. When retrieved
from the MWL SCP, sequence matching couples it to a particular modality and
time interval. As we mentioned, this list is minimal; more likely, a particular
modality will require more data, which should be reflected in the modality’s
DICOM Conformance Statement. If some of those specific attributes are not
provided to the modality, it will likely abort the MWL data transfer, insisting
on a complete attributes list. In other words, if you are working on establishing
MWL connectivity, always start by revising the list of attributes required on the
modality and making sure they can all be provided.
7.5.2
The MWL DIMSE
The MWL DIMSE is nothing more than our good old friend C-Find DIMSE,
which makes at least this part of the MWL implementation easy (Fig. 45). So
no MWL-Rq and MWL-Rsp tables appear in this section; they are identical to
the C-Find-Rq and C-Find-Rsp tables in Sect. 7.4.3. The only obvious change is
in the (0000,0002) attribute value, which is now 1.2.840.10008.5.1.4.31 for the
MWL SOP.
7.6
Basic DICOM Retrieval: C-Get
Let’s drift back a couple of chapters and recall what we learned about C-Store.
If you had carefully read the description of the DICOM Storage SOP (used
to transfer DICOM images) you might have been puzzled by a simple question:
“How do we know what to store?” Indeed, the C-Store SOP transmits
Fig. 45 Modality Worklist SOP