TID 10014 Scanning Length

TID 10014Scanning LengthType: Extensible Order: Significant

NL Rel with Parent VT Concept Name VM Req Type Condition Value Set Constraint
1 NUM EV (113825, DCM, “Scanning Length”) 1 M Units = EV (mm, UCUM, “mm”)
2 NUM EV (113893, DCM, “Length of Reconstructable Volume”) 1 U Units = EV (mm, UCUM, “mm”)
3 NUM EV (113899, DCM, “Exposed Range”) 1 UC IFF TID 10013 row 4 CT Acquisition Type equals (P5-08001, SRT, “Spiral Acquisition”) Units = EV (mm, UCUM, “mm”)
4 NUM EV (113895, DCM, “Top Z Location of Reconstructable Volume”) 1 U Units = EV (mm, UCUM, “mm”)
5 NUM EV (113896, DCM, “Bottom Z Location of Reconstructable Volume”) 1 U Units = EV (mm, UCUM, “mm”)
6 NUM EV (113897, DCM, “Top Z Location of Scanning Length”) 1 U Units = EV (mm, UCUM, “mm”)
7 NUM EV (113898, DCM, “Bottom Z Location of Scanning Length”) 1 U Units = EV (mm, UCUM, “mm”)
8 UIDREF EV (112227, DCM, “Frame of Reference UID”) 1 MC IF any of Rows 4 through 7 are present. If present, shall be the same UID as in the images reconstructed from this irradiation event.

Content Item Descriptions

Row 1 For Spiral scanning, the scanning length is normally the table travel in mm during the tube loading (see Figure A-16). For Sequenced scanning, the scanning length is the table travel between consecutive scans times the number of scans. For Stationary and Free scanning, the scanning length is the nominal width of the total collimation.
Row 2 The length of the reconstructable volume is the maximum z-range between the outermost edges of the top and bottom slices that can be reconstructed from the acquisition. For Spiral scanning, the length of reconstructable volume is the z-range between the outermost beginning of the first reconstructable slice and the outermost end of the last reconstructable slice (see Figure A-16). For Sequenced scanning, the length of reconstructable volume is the z-range between the outermost beginning of the first slice and the outermost end of the last slice (i.e., including any skip). For Stationary and Free scanning, the length of reconstructable volume is the nominal width of the total collimation.
Row 3 For Spiral scanning, the exposed range is as defined in IEC 60601-2-44 (Ed. 3) 302.115(b) (see Figure A-16). Exposed range is not defined for other modes of scanning.
Rows 4-5 The Top and Bottom Z Locations of the Reconstructable Volume are independent of the slice width of any actual reconstructed slices. They are measured from the edges of the volume, and hence are not equal to the Z locations encoded in the images of any actual reconstructed slices, which are recorded as the center of the slice.
Rows 4-7 These locations are patient (not table or gantry) relative, to allow them to be defined in the Patient Coordinate System and hence related to the Image Position (Patient) in the reconstructed images. They are are also defined in terms of the top (towards the patient’s head), and bottom (towards the patient’s feet) of the corresponding ranges, in order to make them independent of whether the scan starts at the top or the bottom or shuttles back and forth in between (see Figure A-16).

[pic]

Figure A-16 Spiral Acquisition Parameters

TID 10015 CT Dose Check Details

This template records details related to the use of the NEMA Dose Check Standard (NEMA XR-25-2010).

TID 10015 CT DOSE CHECK DETAILS Type: Extensible Order: Significant

NL Rel with Parent VT Concept Name VM Req Type Condition Value Set Constraint
1 CONTAINER EV (113900, DCM, “Dose Check Alert Details”) 1 MC IF the scanning device has implemented dose alerts
2 > CONTAINS CODE EV (113901, DCM, “DLP Alert Value Configured”) 1 M DCID (230) Yes-No
3 > CONTAINS CODE EV (113902, DCM, “CTDIvol Alert Value Configured”) 1 M DCID (230) Yes-No
4 > CONTAINS NUM EV (113903, DCM, “DLP Alert Value”) 1 MC IFF value of Row 2 is (R-0038D,SRT, “Yes”) Units = EV (mGy.cm, UCUM, “mGy.cm”)
5 > CONTAINS NUM EV (113904, DCM, “CTDIvol Alert Value”) 1 MC IFF value of Row 3 is (R-0038D,SRT, “Yes”) Units = EV (mGy, UCUM, “mGy”)
6 > CONTAINS NUM EV(113905, DCM, “Accumulated DLP Forward Estimate”) 1 MC IF Accumulated DLP Forward Estimate (Row 6) exceeds DLP Alert Value (Row 4) Units = EV (mGy.cm, UCUM, “mGy.cm”)
7 > CONTAINS NUM EV (113906, DCM, “Accumulated CTDIvol Forward Estimate”) 1 MC IF Accumulated CTDIvol Forward Estimate (Row 7) exceeds CTDIvol Alert Value (Row 5) Units = EV (mGy, UCUM, “mGy”)
8 > CONTAINS TEXT EV (113907, DCM, “Reason for Proceeding”) 1 UC IFF Accumulated DLP Forward Estimate (Row 6) exceeds DLP Alert Value (Row 4) or Accumulated CTDIvol Forward Estimate (Row 7) exceeds CTDIvol Alert Value (Row 5)
9 > CONTAINS INCLUDE DTID (1020) Person Participant 1 MC IF Accumulated DLP Forward Estimate (Row 6) exceeds DLP Alert Value (Row 4) or Accumulated CTDIvol Forward Estimate (Row 7) exceeds CTDIvol Alert Value (Row 5) $PersonProcedureRole = EV (113850, DCM, “Irradiation Authorizing”)
10 CONTAINER EV (113908, DCM, “Dose Check Notification Details”) 1 MC IF the scanning device has implemented dose notifications
11 > CONTAINS CODE EV (113909, DCM, “DLP Notification Value Configured”) 1 M DCID (230) Yes-No
12 > CONTAINS CODE EV (113910, DCM, “CTDIvol Notification Value Configured”) 1 M DCID (230) Yes-No
13 > CONTAINS NUM EV (113911, DCM, “DLP Notification Value”) 1 MC IFF value of Row 11 is (R-0038D,SRT, “Yes”) Units = EV (mGy.cm, UCUM, “mGy.cm”)
14 > CONTAINS NUM EV (113912, DCM, “CTDIvol Notification Value”) 1 MC IFF value of Row 12 is (R-0038D,SRT, “Yes”) Units = EV (mGy, UCUM, “mGy”)
15 > CONTAINS NUM EV (113913, DCM, “DLP Forward Estimate”) 1 MC IF DLP Forward Estimate (Row 15) exceeds DLP Notification Value (Row 13) Units = EV (mGy.cm, UCUM, “mGy.cm”)
16 > CONTAINS NUM EV (113914, DCM, “CTDIvol Forward Estimate”) 1 MC IF CTDIvol Forward Estimate (Row 16) exceeds CTDIvol Notification Value (Row 14) Units = EV (mGy, UCUM, “mGy”)
17 > CONTAINS TEXT EV (113907, DCM, “Reason for Proceeding”) 1 UC IFF DLP Forward Estimate (Row 15) exceeds DLP Notification Value (Row 13) or CTDIvol Forward Estimate (Row 16) exceeds CTDIvol Notification Value (Row 14)
18 > CONTAINS INCLUDE DTID (1020) Person Participant 1 UC IFF DLP Forward Estimate (Row 15) exceeds DLP Notification Value (Row 13) or CTDIvol Forward Estimate (Row 16) exceeds CTDIvol Notification Value (Row 14) $PersonProcedureRole = EV (113850, DCM, “Irradiation Authorizing”)

Content Item Descriptions

Row 1 Container for Dose Check Alert details.
Row 2 Indicates whether a DLP Alert Value was configured (e.g. by the institution) for the exam to which this irradiation event belongs.
Row 3 Indicates whether a CTDIvol Alert Value was configured (e.g. by the institution) for the exam to which this irradiation event belongs.
Row 4 The configured value applicable to the current exam which would trigger an alert if the accumulated DLP were projected to exceed it.
Row 5 The configured value applicable to the current exam which would trigger an alert if the Accumulated CTDIvol at any given location were projected to exceed it.
Row 6 The value estimated prior to performing this irradiation event of the projected DLP accumulated during this exam, including this irradiation event. The estimate may include assumptions such as those described in NEMA XR 25-2010.
Row 7 The value estimated prior to performing this irradiation event of the projected CTDIvol accumulated during this exam, including this irradiation event. The value is for the location with the highest estimated accumulation. The actual location is not recorded. The estimate may include assumptions such as those described in NEMA XR 25-2010.
Row 8 The reason provided by the operator for proceeding with an irradiation event projected to exceed an alert value.
Row 9 Person responsible for authorizing irradiation projected to exceed an alert value.
Row 10 Container for Dose Check Notification details.
Row 11 Indicates whether a DLP Notification Value was configured (e.g. by the institution) for the Protocol Element Group to which this irradiation event corresponds.
Row 12 Indicates whether a CTDIvol Notification Value was configured (e.g. by the institution) for the Protocol Element Group to which this irradiation event corresponds.
Row 13 The configured value applicable to the current irradiation event which would trigger a notification if the DLP were projected to exceed it.
Row 14 The configured value applicable to the current irradiation event which would trigger a notification if the CTDIvol were projected to exceed it.
Row 15 The value estimated prior to performing this irradiation event of the DLP for this irradiation event. The estimate may include assumptions such as those described in NEMA XR 25-2010.
Row 16 The value estimated prior to performing this irradiation event of the CTDIvol for this irradiation event. The value is for the location with the highest estimated value. The actual location is not recorded. The estimate may include assumptions such as those described in NEMA XR 25-2010.
Row 17 The reason provided by the operator for proceeding with an irradiation event projected to exceed a notification value.
Row 18 Person responsible for authorizing irradiation projected to exceed a notification value.