TID 10012 CT Accumulated Dose Data

This general template provides detailed information on CT X-Ray dose value accumulations over several irradiation events from the same equipment and over the scope of accumulation specified for the report (typically a Study or a Performed Procedure Step).

TID 10012 CT ACCUMULATED DOSE DATA Type: Extensible Order: Significant

NL Rel with Parent VT Concept Name VM Req Type Condition Value Set Constraint
1 CONTAINER EV (113811, DCM, ”CT Accumulated Dose Data”) 1 M
2 > CONTAINS NUM EV (113812, DCM, “Total Number of Irradiation Events”) 1 M Units = EV ({events} UCUM, “events”)
3 > CONTAINS NUM EV (113813, DCM, “CT Dose Length Product Total”) 1 M Units = EV (mGy.cm, UCUM, “mGy.cm”)
4 > CONTAINS NUM EV (113814, DCM, “CT Effective Dose Total”) 1 U Units = EV (mSv, UCUM, “mSv”)
5 >> HAS PROPERTIES TEXT EV (121406,DCM, “Reference Authority”) 1 MC XOR row 6
6 >> HAS PROPERTIES CODE EV (121406,DCM, “Reference Authority”) 1 MC XOR row 5 DCID (10015) CT Dose Reference Authority
7 >> HAS CONCEPT MOD CODE EV (G-C036,SRT, “Measurement Method”) 1 M DCID (10011) Effective Dose Evaluation Method
8 >> HAS PROPERTIES TEXT EV (113815,DCM, “Patient Model”) 1 MC IF the value of row 7 equals (113800, DCM, “DLP to E conversion via MC computation”) or equals (113801, DCM, “CTDIfreeair to E conversion via MC computation”)
9 >> HAS PROPERTIES CONTAINER EV (113816, DCM, “Condition Effective Dose measured”) 1 MC IF the value of row 7 equals (113802, DCM, “DLP to E conversion via measurement”) or equals (113803, DCM, “CTDIfreeair to E conversion via measurement”)
10 >>> CONTAINS TEXT EV (113817,DCM, “Effective Dose Phantom Type”) 1 M
11 >>> CONTAINS TEXT EV (113818, DCM, “Dosimeter Type”) 1 M
12 > CONTAINS TEXT EV (121106, DCM, “Comment”) 1 U
13 > CONTAINS INCLUDE DTID (1021) Device Participant 1 MC Required if the irradiating device is not the recording device and the dose was accumulated on a single device. $DeviceProcedureRole = EV (113859, DCM, “Irradiating Device”)

Content Item Descriptions

Row 2 Total Number of CT irradiation events . A CT irradiation event is one continuous irradiation procedure and is defined through consistent acquisition parameters. In the case of dose modulation the calculations are based on the effective parameters (e.g. the effective mA recorded in the Mean X-Ray Tube Current), and these acquisition parameters are consistent.
Row 3 The Dose Length Product (DLP) is calculated for every irradiation event. The Dose Length Product Total is the sum of the DLP values. The calculation is based on the CTDIvol result of each irradiation event.
Row 4 Effective dose (E, in units of mSv) evaluated as a total over the scope is defined in Row 6 of template TID 10011. Effective dose is defined by the reference in Rows 5 or 6 of this template. It may be calculated from a product of DLP and an ‘Effective Dose Conversion Factor’ (E/DLP). Or it may be calculated from a product of the Mean CTDIfree air and the ratio E/CTDIfree air. The ratios E/DLP or E/CTDIfree air may be evaluated either from computer simulations applying Monte Carlo (MC) sampling techniques or from dosimetric measurements in an anthropomorphic phantom, e.g., the Alderson-Rando phantom.. The specific method used is identified in Rows 7 through 11.
Row 5 - 6 Reference of the base publication defining the Effective Dose, either as a coded value, or a textual bibliographic reference. ICRP Publications shall be referenced using their assigned coded values.
Row 7 Description of the method used for Effective Dose evaluations.
Row 8 Description of the reference-patient mathematical or computational model used when Effective Dose is derived via Monte Carlo simulations of radiation transport in such models. Examples of publications which specify particular reference patient models are NUREG/CR-1159, ORNL/NUREG/TM-367 (1980); NRPB-R186 (1985); GSF-Bericht S-885 (1986); Fill et al., Health Physics Vol. 86 (3): 253-272 (2004).
Row 9 Description of the condition Effective Dose measured
Row 10 Type of Effective Dose phantom used, e.g. Alderson-Rando
Row 11 Type of dosimeter used, e.g. TLD (Thermo Luminescence Dosimeter)
Row 13 The device which produced the irradiation accumulated in this template. I.e. the CT Scanner. This is not required to be present if the information is the same as that already recorded in the Device Observer Context (TID 1004) encoded via the inclusion of Observer Context (TID 1002) in TID 10011 Row 4, which in turn may be absent if identical to the content in the Enhanced General Equipment Module, or if more than one device produced the accumulated irradiation.