DICOM PS3.17 2019b - Explanatory Information

GGGG Patient Radiation Dose Structured Report Document (Informative)

This Annex contains examples of the use of Patient Radiation Dose templates within Patient Radiation Dose Structured Report Documents.

GGGG.1 Skin Dose Map Example

The following example shows the report of the skin dose map calculated from the dose delivered during an X-Ray interventional cardiology procedure.

The calculation uses a Radiation Dose SR provided by a Single Plane X-Ray Angiography equipment of the manufacturer "A". The Radiation Dose SR is created during one procedure step, corresponding to the coronary stenting of an adult male of 83 kg and 179 cm height.

The skin dose calculations are performed by an application on a separated workstation of the manufacturer "B", operated by the medical physicist, who is logged into the workstation at the time of the creation of the Patient Radiation Dose Structured Report document.

The dose calculation application generates a Patient Radiation Dose Structured Report document and a Secondary Capture Image containing an image of the dose distribution over the deployed skin of the patient model.

The dose calculation application uses the following settings and assumptions:

  • RDSR Source Data:

    • All the Irradiation Event UIDs are used in the calculation of the skin dose map.

  • Patient Model:

    • The patient model is a combination of two elliptic cylinders to represent the chest and neck of the patient.

    • The actual dimensions of the model are determined by the age, gender, height, and weight of the patient.

    • In this example the exact height and weight of the patient are used to create the model. The resulting elliptic cylinder for the chest of the model is 31 cm in the AP dimension and 74 cm in the lateral dimension.

    • The application creates internally a 3D voxelized model that is stored in a DICOM SOP Instance.

  • Patient Model Registration:

    • The distance from the top of the patient's head to the head of the table (measured during the procedure) is known. The location of the patient head and table head are stored in a Spatial Fiducials SOP instance.

    • The application uses fiducials to register the patient model with the data of the source Radiation Dose SR.

    • A-priori knowledge of the distance from the table head to the system Isocenter at table zero position is calibrated offline.

    • The table tilt, cradle, and rotation angles are ignored because the description of the acquisition geometry is incomplete in the Radiation Dose SR. Only table translations relative to the Isocenter are considered in the calculations.

  • Beam Attenuators:

    • A-priori knowledge of the model of the table and mattress (i.e., shape, dimensions, and absorption material) is calibrated offline, and it is referenced internally by the application. The model contains the same coordinate system as the one used in the equipment referenced in the Radiation Dose SR, so there is no need of another registration SOP instance.

    • The X-Ray filter information from the source Radiation Dose SR is used by the application. There is no other a-priori knowledge of the X-Ray filtration.

Table GGGG.1-1. Skin Dose Map Example

Node

Code Meaning of Concept Name

Code or Example Value

Comment

1

Patient Radiation Dose Report

TID 10030

1.1

Language of Content Item and Descendants

(En, IETF4646, "English")

TID 1204

1.2

Observer Type

(121007, DCM, "Device")

TID 1002

1.3

Device Observer UID

1.2.3.4.566.1.5

TID 1004

1.4

Device Observer Name

MedPhys-01

TID 1004

1.5

Device Observer Manufacturer

Manufacturer B

TID 1004

1.6

Device Observer Model Name

Dose Workstation v1

TID 1004

1.7

Observer Type

(121006, DCM, "Person")

TID 1002

1.8

Person Observer Name

Doe^John^^Dr^PhD

TID 1003

1.9

Person Observer's Role in the Organization

(C1708969, UMLS, "Medical Physicist")

TID 1003

1.10

Radiation Dose Estimate

TID 10031

1.10.1

Radiation Dose Estimate Name

Skin Dose Map

TID 10031

1.10.2

Comment

Single Plane XA

TID 10031

1.10.3

Radiation Dose Estimate Methodology

TID 10033

1.10.3.1

SR Instance Used

Radiation Dose SR #1

1.10.3.1.1

SOP Class UID

1.2.840.1008.5.1.4.1.1.88.67

1.10.3.1.2

SOP Instance UID

1.2.3.4.566.77.1

1.10.3.1.3

Spatial Fiducials

Spatial Fiducials

1.10.3.1.3.1

SOP Class UID

1.2.840. 1008.5.1.4.1.1.66.2

1.10.3.1.3.2

SOP Instance UID

1.2.3.4.44.222.33.1

1.10.3.2

Patient Radiation Dose Model

TID 10033

1.10.3.2.1

Patient Model Type

(128418, DCM, "Simple Object Model")

TID 10033

1.10.3.2.2

Radiation Transport Model Type

(128422, DCM, "Voxelized Radiation Transport Model")

TID 10033

1.10.3.2.3

Patient Radiation Dose Model Data

Parametric map

1.10.3.1.3.1

SOP Class UID

1.2.840.1008.5.1.4.1.1.30

1.10.3.1.3.2

SOP Instance UID

1.2.3.43.44.55.1

1.10.3.2.4

Patient Radiation Dose Model Reference

DOI:1.2.3.4

TID 10033

1.10.3.2.5

Comment

Combined Elliptic Cylinders

TID 10033

1.10.3.2.6

Patient Model Demographics

TID 10033

1.10.3.2.6.1

Model Minimum Age

18 (a, UCUM, "year")

TID 10033

1.10.3.2.6.2

Model Maximum Age

90 (a, UCUM, "year")

TID 10033

1.10.3.2.6.3

Model Patient Sex

(M, DCM, "Male")

TID 10033

1.10.3.2.6.4

Model Minimum Weight

83 (kg, UCUM, "kilogram")

TID 10033

1.10.3.2.6.5

Model Maximum Weight

83 (kg, UCUM, "kilogram")

TID 10033

1.10.3.2.6.6

Model Minimum Height

179 (cm, UCUM, "Centimeter")

TID 10033

1.10.3.2.6.7

Model Maximum Height

179 (cm, UCUM, "Centimeter")

TID 10033

1.10.3.2.7

Patient Model Registration

TID 10033

1.10.3.2.7.1

Comment

Distance from the top of patient's head to the head of the table = 10 cm

TID 10033

1.10.3.2.7.2

Registration Method

(125022, DCM, "Fiducial Alignment")

TID 10033

1.10.3.2.7.3

Spatial Registration

Spatial Registration

1.10.3.1.3.1

SOP Class UID

1.2.840. 1008.5.1.4.1.1.66.1

1.10.3.1.3.2

SOP Instance UID

1.2.3.4.44.3.2.11

1.10.3.3

X-Ray Beam Attenuator

TID 10033

1.10.3.3.1

Attenuator Category

(128459, DCM, "Table")

TID 10033

1.10.3.3.2

Equivalent Attenuator Material

(256501007, SCT, "Carbon fiber")

TID 10033

1.10.3.3.3

Equivalent Attenuator Thickness

100 (mm, UCUM, "Millimeter")

TID 10033

1.10.3.3.4

Attenuator Description

X-Ray Table with Mattress

TID 10033

1.10.3.3.5

X-Ray Beam Attenuator Model

TID 10033

1.10.3.3.5.1

Radiation Transport Model Type

(128421, DCM, "Geometric Radiation Transport Model")

TID 10033

1.10.3.3.5.2

X-Ray Beam Attenuator Model Reference

DOI:1.4.2.3

TID 10033

1.10.3.4

Radiation Dose Estimate Method

TID 10033

1.10.3.4.1

Radiation Dose Estimate Method Type

(128480, DCM, "Analytical Algorithm")

TID 10033

1.10.3.4.2

Radiation Dose Estimate Parameters

TID 10034

1.10.3.4.2.1

(128433, DCM, "Tissue Air Ratio")

1.06 ({ratio}, UCUM, "ratio")

TID 10034

1.10.3.4.2.1.1

Radiation Dose Estimate Parameter Type

(C70774, NCIt, "Unit Conversion Factor")

TID 10034

1.10.3.4.2.2

(128408, DCM, "Patient AP Dimension")

31 (cm, UCUM, "Centimeter")

TID 10034

1.10.3.4.2.2.1

Radiation Dose Estimate Parameter Type

(121206, DCM, "Distance")

TID 10034

1.10.3.4.2.3

(128409, DCM, "Patient Lateral Dimension")

74 (cm, UCUM, "Centimeter")

TID 10034

1.10.3.4.2.3.1

Radiation Dose Estimate Parameter Type

(121206, DCM, "Distance")

TID 10034

1.10.3.4.2.4

(MyCode001, 99MyScheme, "Linear attenuation coefficient of the table and mattress")

0.010536 (/cm, UCUM, "/Centimeter")

TID 10034

1.10.3.4.3

Radiation Dose Estimate Method Reference

DOI:4.2.13.4

TID 10033

1.10.4

Radiation Dose Estimate Representation

TID 10032

1.10.4.1

Distribution Representation

(128485, DCM, "Skin Dose Map")

TID 10032

1.10.4.2

Radiation Dose Representation Data

TID 10032

1.10.4.2.1

SOP Class UID

1.2.840.10008.5.1.4.1.1.7

Secondary Capture

1.10.4.2.2

SOP Instance UID

1.2.3.1.2.3.3

1.10.4.3

Organ

(181469002, SCT, "Skin")

TID 10032

1.10.4.4

Comment

2D map of the dose on the deployed skin

TID 10032

1.10.5

Organ Radiation Dose Information

TID 10031

1.10.5.1

Organ

(181469002, SCT, "Skin")

TID 10031

1.10.5.2

Comment

Skin in the area of the chest and neck

TID 10031

1.10.5.3

(DCM, 128531, "Maximum Absorbed Radiation Dose")

3000 (mGy, UCUM, "mGy")

TID 10031

1.10.5.3.1

(371884006, SCT, "+/-, range of measurement uncertainty")

750 (mGy, UCUM, "mGy")

TID 10031

1.11

Comment

Skin Dose Map Report

TID 10030


DICOM PS3.17 2019b - Explanatory Information