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The DICOM standard's information model uses the hierarchy of studies, study components, series and instances to identify objects such as images, reports, waveforms etc. A single instance of the DICOM object is uniquely identifiable but sharing the context at the level above the object instance level is useful in real world practice. To facilitate such context sharing the CCOW standard defines separate context subjects to represent each of these levels.
DICOM Study Identity subjects have the following attributes:
| Subject Label |
For DICOM study subject: "DICOMStudy" For DICOM study component subject: "DICOMStudyComponent" For DICOM series subject: "DICOMSeries" For DICOM instance subject: "DICOMInstance" |
| Subject type | Identity |
| Sunchronization | Constant |
| Security | None |
| Subject Dependencies | Dependent upon patient subject |
| Mapping Agent Coupon Value |
For DICOM study subject: -6 For DICOM study component subject: -7 For DICOM series subject: -8 For DICOM instance subject: -9 |
DICOM uses globally unique ISO UIDs to identify an instance of a DICOM object. There is no need to use context suffix to differentiate DICOM subjects.
The DICOM study identity subject represents a DICOM study object for a specific patient. DICOM Study Identity subjects have the following standard context data item. An application should set the value for the item listed in the following table:
| DICOM Study Identifier Item Name | Meaning | Data Type | Semantic Constraints of Values | Case Sensitivity |
|---|---|---|---|---|
| DICOMStudy.Id.InstanceUID | The DICOM Study Instance UID (0020,000D) attribute value of a composite DICOM object | HD | Must follow the DICOM UID encoding rules. DICOM PS 3.5 | No |
An application can optionally set values for the corroborating items listed in the following table:
| DICOM Study Subject Corroborating Item Name | Meaning | Data Type | Semantic Constraints of Values | Case Sensitivity |
|---|---|---|---|---|
| DICOMStudy.Co.Placer_Order_Number.Suffix | Placer Order Number per OBR-2 | EI | None | No |
| DICOMStudy.Co.Filler_Order_Number.Suffix | Filler Order Number per OBR-3 | EI | None | No |
|
DICOMStudy.Co.Accession_Number.Suffix
Note: For future version of the standard |
OMI Imaging Order Message (Event O23) | EI | None | No |
Examples of DICOM Study subject items are listed in the following table:
| Example Item Names | Example Item Values |
|---|---|
| DICOMStudy.Id.InstanceUID | ^1.2.840.114819.6.48.2327.1^ISO |
| DICOMStudy.Co.Filler_Order_Number.ISHIS | 0161234515980723134223 |
The DICOM Study Component Identity subject represents a specific DICOM study component object for a patient. DICOM Study Component Identity subjects have the following standard context data items. An application should set values for all of the items listed in the following table:
| DICOM Study Component Identifier Item Name | Meaning | Data type | Semantic Constraints on Values | Case Sensitivity |
|---|---|---|---|---|
| DICOMStudyComponent.Id.InstanceUID | See below | HD | Must follow the DICOM UID encoding rules. DICOM PS 3.5 | No |
| DICOMStudyComponent.Id.ClassUID | See below | HD | Must follow the DICOM UID encoding rules. DICOM PS 3.5 | No |
The DICOMStudyComponent.Id.InstanceUID item can have one of the following values:
The DICOMStudyComponent.Id.ClassUID item can have one of the following values:
Examples of DICOM Study Subject Items are listed in the following table:
| Example Item names | Example Item Values |
|---|---|
| DICOMStudyComponent.Id.InstanceUID | ^1.2.840.112459.26.48.2347.1^ISO |
| DICOMStudyComponent.Id.ClassUID | ^1.2.840.10008.3.1.2.3.3^ISO |
The DICOM Series Identity subject represents a DICOM series object for a specific patient. DICOM Series subjects have the following standard context data items:
| Dicom Series Identifier Item Name | Meaning | Data Type | Semantic Constraints on Values | Case Sensitivity |
|---|---|---|---|---|
| DICOMSeries.Id.InstanceUID | The DICOM Series Instance UID (0020,000E) attribute value of a composite DICOM object | HD | Must follow the DICOM UID encoding rules. DICOM PS 3.5 | No |
Example of DICOM Series subject items are listed in the following table:
| Example Item Names | Example Item Values |
|---|---|
| DICOMSeries.Id.InstanceUID | ^1.2.840.114789.6.48.2367.25.566^ISO |
The DICOM Instance Identity subject represents a DICOM object instance such as image, waveform or structured report for a specific patient. DICOM Instance subjects have the following standard context data items:
| Dicom Series Identifier Item Name | Meaning | Data Type | Semantic Constraints on Values | Case Sensitivity |
|---|---|---|---|---|
| DICOMInstance.Id.InstanceUID | See below | HD | Must follow the DICOM UID encoding rules. DICOM PS 3.5 | No |
| DICOMInstance.Id.ClassUID | See below | HD | Must follow the DICOM UID encoding rules. DICOM PS 3.5 | No |
| DICOMInstance.Id.ReferencedFrameNumber | Frame number of multi-frame image object | NM | No |
An application should set the DICOMInstance.Id.InstanceUID and DICOMInstance.Id.ClassUID when setting DICOM instance context.
The DICOM SOP Instance UID (0008, 0018) attribute value of a composite DICOM storage SOP class object should be used as DICOMInstance.Id.InstanceUID item value. The DICOM SOP Class UID (0008, 0016) attribute value of a composite DICOM storage SOP class object should be used as DICOMInstance.Id.ClassUID item value.
Examples of DICOM Instance subject items are listed in the following table. This case corresponds to selected frames of an X-Ray Angiographic Image Storage object instance:
| Example Item Names | Example Item Values |
|---|---|
| DICOMInstance.Id.InstanceUID | ^1.2.840.113619.6.48.2367.1.56.23^ISO |
| DICOMInstance.Id.ClassUID | ^ 1.2.840.10008.5.1.4.1.1.12.1^ISO |
| DICOMInstance.Id.ReferencedFrameNumber | 1~15~17~22 |