Main DICOM Tags in DB¶
Introduction¶
By default, Orthanc is saving a predefined subset of DICOM Tags
in the DB. These are called the MainDicomTags
.
Since they are stored in DB, these tags can be retrieved very quickly and can conveniently be used for filtering/finding resources while, to access other DICOM tags, Orthanc needs to re-open the DICOM file which is much slower.
As of Orthanc 1.4.2 (and later), the predefined list is:
- Patients:
- PatientName
- PatentID
- PatientBirthDate
- PatientSex
- OtherPatientIDs
- Studies:
- StudyDate
- StudyTime
- StudyID
- StudyDescription
- AccessionNumber
- StudyInstanceUID
- RequestedProcedureDescription
- InstitutionName
- RequestingPhysician
- ReferringPhysicianName
- Series:
- SeriesDate
- SeriesTime
- Modality
- Manufacturer
- StationName
- SeriesDescription
- BodyPartExamined
- SequenceName
- ProtocolName
- SeriesNumber
- CardiacNumberOfImages
- ImagesInAcquisition
- NumberOfTemporalPositions
- NumberOfSlices
- NumberOfTimeSlices
- SeriesInstanceUID
- ImageOrientationPatient
- SeriesType
- OperatorsName
- PerformedProcedureStepDescription
- AcquisitionDeviceProcessingDescription
- ContrastBolusAgent
- Instances:
- InstanceCreationDate
- InstanceCreationTime
- AcquisitionNumber
- ImageIndex
- InstanceNumber
- NumberOfFrames
- TemporalPositionIdentifier
- SOPInstanceUID
- ImagePositionPatient
- ImageComments
- ImageOrientationPatient
Adding more tags in DB¶
Since version 1.11.0, it is possible to
customize a list of ExtraMainDicomTags
to include in the DB
through a new configuration option.
Since version 1.11.1, it is possible to
include sequences in ExtraMainDicomTags
. However, this should be
considered as an “experimental” feature and you should not store large
sequences (> 64KB) or sequences containing binary tags.
Below is a sample configuration that is well suited to optimize DICOMWeb routes in general, especially when you are using a DICOMWeb viewer:
{
"ExtraMainDicomTags" : {
"Instance" : [
"Rows",
"Columns",
"ImageType",
"SOPClassUID",
"ContentDate",
"ContentTime",
"FrameOfReferenceUID",
"PixelSpacing",
"SpecificCharacterSet",
"BitsAllocated",
"BitsStored"
],
"Series" : [
"TimezoneOffsetFromUTC",
"PerformedProcedureStepStartDate",
"PerformedProcedureStepStartTime",
"RequestAttributesSequence"
],
"Study": [
"TimezoneOffsetFromUTC"
],
"Patient": []
}
}
This configuration will apply only to newly added resources
in Orthanc. If you want to apply this change to resources
already in Orthanc, you may call the /studies/../reconstruct
API route or use the Housekeeper plugin
to automate this reconstruction process.
Warnings¶
Since Orthanc 1.11.0, Orthanc issues a warning everytime it opens a DICOM file to access a DICOM tag that could have been saved in DB.
Orthanc will also issue a warning everytime it accesses a resource
that has been saved with a ExtraMainDicomTags
configuration that
is different from the current one inviting you to call the
/reconstruct
route to fix this.
These warnings can be enabled/disabled through this configuration:
{
"Warnings" : {
"W001_TagsBeingReadFromStorage": true,
"W002_InconsistentDicomTagsInDb": true
}
}