DICOM PS3.16 2022d  Content Mapping Resource 

This general Template provides detailed information on CT XRay 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).
Table TID 10012. CT Accumulated Dose Data
IFF irradiation events within the scope of accumulation use different phantoms for estimating the recorded perevent DLP (i.e., the values of TID 10013 “CT Irradiation Event Data” Row 23 are not all the same). 

IF the value of Row 7 = (113800, DCM, "DLP to E conversion via MC computation") or equals (113801, DCM, "CTDIfreeair to E conversion via MC computation") 

IF the value of Row 7 = (113802, DCM, "DLP to E conversion via measurement") or equals (113803, DCM, "CTDIfreeair to E conversion via measurement") 

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") 
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 XRay Tube Current), and these acquisition parameters are consistent. 

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 CTDI_{vol} result of each irradiation event. If the individual DLP values are calculated using different phantoms, the separate perphantom subtotals may be encoded in Row 3a. 

The sum of the perevent DLP values with the specified phantom. 

The phantom used for the phantomspecific subtotal DLP estimate; shall be that specified at the irradiation event level in TID 10013 “CT Irradiation Event Data” Row 23 for the events included in the subtotal. 

Effective dose (E, in units of mSv) evaluated as a total over the scope is defined in Row 6 of 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 AldersonRando phantom.. The specific method used is identified in Rows 7 through 11. 

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. 

Description of the method used for Effective Dose evaluations. 

Description of the referencepatient 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/CR1159, ORNL/NUREG/TM367 (1980); NRPBR186 (1985); GSFBericht S885 (1986); Fill et al., Health Physics Vol. 86 (3): 253272 (2004). 

Type of dosimeter used, e.g., TLD (Thermo Luminescence Dosimeter) 

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 2022d  Content Mapping Resource 
