C.3 Standard query/retrieve information models

Three standard Query/Retrieve Information Models are defined in this Annex. Each Query/Retrieve Information Model is associated with a number of SOP Classes. The following three hierarchical Query/Retrieve Information Models are defined:

C.3.1 Patient Root Query/Retrieve Information Model

The Patient Root Query/Retrieve Information Model is based upon a four level hierarchy:

The patient level is the top level and contains Attributes associated with the Patient Information Entity (IE) of the Composite IODs as defined in PS 3.3. Patients IEs are modality independent.

The study level is below the patient level and contains Attributes associated with the Study IE of the Composite IODs as defined in PS 3.3. A study belongs to a single patient. A single patient may have multiple studies. Study IEs are modality independent.

The series level is below the study level and contains Attributes associated with the Series, Frame of Reference and Equipment IEs of the Composite IODs as defined in PS 3.3. A series belongs to a single study. A single study may have multiple series. Series Ies are modality dependent. To accommodate this modality dependence, the set of Optional Keys at the series level includes all Attributes defined at the series level from any Composite IOD defined in PS 3.3.

The lowest level is the composite object instance level and contains Attributes associated with the Composite object IE of the Composite IODs as defined in PS 3.3. A composite object instance belongs to a single series. A single series may contain multiple composite object instances. Most composite object IEs are modality dependent. To accommodate this potential modality dependence, the set of Optional Keys at the composite object instance level includes all Attributes defined at the composite object instance level from any Composite IOD defined in PS 3.3.

C.3.2 Study Root Query/Retrieve Information Model

The Study Root Query/Retrieve Information Model is identical to the Patient Root Query/Retrieve Information Model except the top level is the study level. Attributes of patients are considered to be Attributes of studies.

C.3.3 Patient/Study Only Query/Retrieve Information Model

Retired. See PS 3.4 2004.

C.3.4 Additional Query/Retrieve Attributes

Some optional attributes that may be used in Query/Retrieve Information Models that are not Attributes of an Information Object Definition and, therefore, are not defined in PS 3.3. These attributes are defined in Table C.3-1.

Table C.3-1 ADDITIONAL QUERY/RETRIEVE ATTRIBUTES

Attribute Name Tag Attribute Description
Number of Patient Related Studies (0020,1200) The number of studies that match the Patient level Query/Retrieve search criteria
Number of Patient Related Series (0020,1202) The number of series that match the Patient level Query/Retrieve search criteria
Number of Patient Related Instances (0020,1204) The number of composite object instances that match the Patient level Query/Retrieve search criteria
Number of Study Related Series (0020,1206) The number of series that match the Study level Query/Retrieve search criteria
Number of Series Related Instances (0020,1209) The number of composite object instances in a Series that match the Series level Query/Retrieve search criteria
Number of Study Related Instances (0020,1208) The number of composite object instances that match the Study level Query/Retrieve search criteria
Modalities in Study (0008,0061) All of the distinct values used for Modality (0008,0060) in the Series of the Study.
SOP Classes in Study (0008,0062) The SOP Classes contained in the Study.
Alternate Representation Sequence (0008,3001) A Sequence of Items, each identifying an alternate encoding of an image that matches the Instance level Query/Retrieve search criteria (see C.6.1.1.5.1)

If the SCP manages images in multiple alternate encodings, only one of the alternate encodings of an image is included in the number of object instances.