DICOM PS3.16 2019b - Content Mapping Resource

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).

Type:

Extensible

Order:

Significant

Root:

No

Table TID 10012. CT Accumulated Dose Data

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 Authorities”

7

>>

HAS CONCEPT MOD

CODE

EV (370129005, SCT, "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

Rows 5, 6

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.

Rows 5, 6

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.

Rows 5, 6

Effective dose (E, in units of mSv) evaluated as a total over the scope is defined in Row 6 of Template TID 10011 “CT Radiation Dose”.

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 CTDIfreeair and the ratio E/CTDIfreeair. The ratios E/DLP or E/CTDIfreeair 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 that 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 that 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 TID 1004 “Device Observer Identifying Attributes” encoded via the inclusion of TID 1002 “Observer Context” in TID 10011 “CT Radiation Dose” 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.

DICOM PS3.16 2019b - Content Mapping Resource