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DICOM Conformance Statement

API version 2 is the latest API version and should be used. Go to API version 2 for the latest conformance statement.

The Medical Imaging Server for DICOM supports a subset of the DICOMweb™ Standard. Support includes:

Additionally, the following non-standard API(s) are supported:

All paths below include an implicit base URL of the server, such as https://localhost:63838 when running locally.

The service makes use of REST Api versioning. Do note that the version of the REST API must be explicitly specified as part of the base URL as in the following example:

https://localhost:63838/v1/studies

For more information on how to specify the version when making requests, visit the Api Versioning Documentation.

You can find example requests for supported transactions in the Postman collection.

Preamble Sanitization

The service ignores the 128-byte File Preamble, and replaces its contents with null characters. This ensures that no files passed through the service are vulnerable to the malicious preamble vulnerability. However, this also means that preambles used to encode dual format content such as TIFF cannot be used with the service.

Studies Service

The Studies Service allows users to store, retrieve, and search for DICOM Studies, Series, and Instances. We have added the non-standard Delete transaction to enable a full resource lifecycle.

Store (STOW-RS)

This transaction uses the POST method to Store representations of Studies, Series, and Instances contained in the request payload.

Method Path Description
POST ../studies Store instances.
POST ../studies/{study} Store instances for a specific study.

Parameter study corresponds to the DICOM attribute StudyInstanceUID. If specified, any instance that does not belong to the provided study will be rejected with 43265 warning code.

The following Accept header(s) for the response are supported:

  • application/dicom+json

The following Content-Type header(s) are supported:

  • multipart/related; type="application/dicom"
  • application/dicom

Note: The Server will not coerce or replace attributes that conflict with existing data. All data will be stored as provided.

The following DICOM elements are required to be present in every DICOM file attempting to be stored:

  • StudyInstanceUID
  • SeriesInstanceUID
  • SOPInstanceUID
  • SOPClassUID
  • PatientID

Note: All UIDs must be between 1 and 64 characters long, and only contain alpha numeric characters or the following special characters: ., -. PatientID is validated based on its LO VR type.

Each file stored must have a unique combination of StudyInstanceUID, SeriesInstanceUID and SopInstanceUID. The warning code 45070 will be returned if a file with the same identifiers already exists.

DICOM File Size Limit: there is a size limit of 2GB for a DICOM file by default.

Store Response Status Codes

Code Description
200 (OK) All the SOP instances in the request have been stored.
202 (Accepted) Some instances in the request have been stored but others have failed.
204 (No Content) No content was provided in the store transaction request.
400 (Bad Request) The request was badly formatted. For example, the provided study instance identifier did not conform the expected UID format.
401 (Unauthorized) The client is not authenticated.
406 (Not Acceptable) The specified Accept header is not supported.
409 (Conflict) None of the instances in the store transaction request have been stored.
415 (Unsupported Media Type) The provided Content-Type is not supported.
503 (Service Unavailable) The service is unavailable or busy. Please try again later.

Store Response Payload

The response payload will populate a DICOM dataset with the following elements:

Tag Name Description
(0008, 1190) RetrieveURL The Retrieve URL of the study if the StudyInstanceUID was provided in the store request and at least one instance is successfully stored.
(0008, 1198) FailedSOPSequence The sequence of instances that failed to store.
(0008, 1199) ReferencedSOPSequence The sequence of stored instances.

Each dataset in the FailedSOPSequence will have the following elements (if the DICOM file attempting to be stored could be read):

Tag Name Description
(0008, 1150) ReferencedSOPClassUID The SOP class unique identifier of the instance that failed to store.
(0008, 1155) ReferencedSOPInstanceUID The SOP instance unique identifier of the instance that failed to store.
(0008, 1197) FailureReason The reason code why this instance failed to store.
(0074, 1048) FailedAttributesSequence The sequence of ErrorComment that includes the reason for each failed attribute.

Each dataset in the ReferencedSOPSequence will have the following elements:

Tag Name Description
(0008, 1150) ReferencedSOPClassUID The SOP class unique identifier of the instance that was stored.
(0008, 1155) ReferencedSOPInstanceUID The SOP instance unique identifier of the instance that was stored.
(0008, 1190) RetrieveURL The retrieve URL of this instance on the DICOM server.

An example response with Accept header application/dicom+json:

{
  "00081190":
  {
    "vr":"UR",
    "Value":["http://localhost/studies/d09e8215-e1e1-4c7a-8496-b4f6641ed232"]
  },
  "00081198":
  {
    "vr":"SQ",
    "Value":
    [{
      "00081150":
      {
        "vr":"UI","Value":["cd70f89a-05bc-4dab-b6b8-1f3d2fcafeec"]
      },
      "00081155":
      {
        "vr":"UI",
        "Value":["22c35d16-11ce-43fa-8f86-90ceed6cf4e7"]
      },
      "00081197":
      {
        "vr":"US",
        "Value":[43265]
      }
    }]
  },
  "00081199":
  {
    "vr":"SQ",
    "Value":
    [{
      "00081150":
      {
        "vr":"UI",
        "Value":["d246deb5-18c8-4336-a591-aeb6f8596664"]
      },
      "00081155":
      {
        "vr":"UI",
        "Value":["4a858cbb-a71f-4c01-b9b5-85f88b031365"]
      },
      "00081190":
      {
        "vr":"UR",
        "Value":["http://localhost/studies/d09e8215-e1e1-4c7a-8496-b4f6641ed232/series/8c4915f5-cc54-4e50-aa1f-9b06f6e58485/instances/4a858cbb-a71f-4c01-b9b5-85f88b031365"]
      }
    }]
  }
}

Store Failure Reason Codes

Code Description
272 The store transaction did not store the instance because of a general failure in processing the operation.
43264 The DICOM instance failed the validation.
43265 The provided instance StudyInstanceUID did not match the specified StudyInstanceUID in the store request.
45070 A DICOM instance with the same StudyInstanceUID, SeriesInstanceUID and SopInstanceUID has already been stored. If you wish to update the contents, delete this instance first.
45071 A DICOM instance is being created by another process, or the previous attempt to create has failed and the cleanup process has not had chance to clean up yet. Please delete the instance first before attempting to create again.
45063 A DICOM instance Data Set does not match SOP Class. The Studies Store Transaction (Section 10.5) observed that the Data Set did not match the constraints of the SOP Class during storage of the instance.

Store Error Codes

Code Description
100 The provided instance attributes did not meet the validation criteria.

Retrieve (WADO-RS)

This Retrieve Transaction offers support for retrieving stored studies, series, instances and frames by reference.

Method Path Description
GET ../studies/{study} Retrieves all instances within a study.
GET ../studies/{study}/metadata Retrieves the metadata for all instances within a study.
GET ../studies/{study}/series/{series} Retrieves all instances within a series.
GET ../studies/{study}/series/{series}/metadata Retrieves the metadata for all instances within a series.
GET ../studies/{study}/series/{series}/instances/{instance} Retrieves a single instance.
GET ../studies/{study}/series/{series}/instances/{instance}/metadata Retrieves the metadata for a single instance.
GET ../studies/{study}/series/{series}/instances/{instance}/rendered Retrieves an instance rendered into an image format
GET ../studies/{study}/series/{series}/instances/{instance}/frames/{frames} Retrieves one or many frames from a single instance. To specify more than one frame, a comma separate each frame to return, e.g. /studies/1/series/2/instance/3/frames/4,5,6
GET ../studies/{study}/series/{series}/instances/{instance}/frames/{frame}/rendered Retrieves a single frame rendered into an image format

Retrieve instances within Study or Series

The following Accept header(s) are supported for retrieving instances within a study or a series:

  • multipart/related; type="application/dicom"; transfer-syntax=*
  • multipart/related; type="application/dicom"; (when transfer-syntax is not specified, 1.2.840.10008.1.2.1 is used as default)
  • multipart/related; type="application/dicom"; transfer-syntax=1.2.840.10008.1.2.1
  • multipart/related; type="application/dicom"; transfer-syntax=1.2.840.10008.1.2.4.90
  • */* (when transfer-syntax is not specified, * is used as default and mediaType defaults to application/dicom)

Retrieve an Instance

The following Accept header(s) are supported for retrieving a specific instance:

  • application/dicom; transfer-syntax=*
  • multipart/related; type="application/dicom"; transfer-syntax=*
  • application/dicom; (when transfer-syntax is not specified, 1.2.840.10008.1.2.1 is used as default)
  • multipart/related; type="application/dicom" (when transfer-syntax is not specified, 1.2.840.10008.1.2.1 is used as default)
  • application/dicom; transfer-syntax=1.2.840.10008.1.2.1
  • multipart/related; type="application/dicom"; transfer-syntax=1.2.840.10008.1.2.1
  • application/dicom; transfer-syntax=1.2.840.10008.1.2.4.90
  • multipart/related; type="application/dicom"; transfer-syntax=1.2.840.10008.1.2.4.90
  • */* (when transfer-syntax is not specified, * is used as default and mediaType defaults to application/dicom)

Retrieve Frames

The following Accept headers are supported for retrieving frames:

  • multipart/related; type="application/octet-stream"; transfer-syntax=*
  • multipart/related; type="application/octet-stream"; (when transfer-syntax is not specified, 1.2.840.10008.1.2.1 is used as default)
  • multipart/related; type="application/octet-stream"; transfer-syntax=1.2.840.10008.1.2.1
  • multipart/related; type="image/jp2"; (when transfer-syntax is not specified, 1.2.840.10008.1.2.4.90 is used as default)
  • multipart/related; type="image/jp2";transfer-syntax=1.2.840.10008.1.2.4.90
  • application/octet-stream; transfer-syntax=* for single frame retrieval
  • */* (when transfer-syntax is not specified, * is used as default and mediaType defaults to application/octet-stream)

Retrieve Transfer Syntax

When the requested transfer syntax is different from original file, the original file is transcoded to requested transfer syntax. The original file needs to be one of below formats for transcoding to succeed, otherwise transcoding may fail:

  • 1.2.840.10008.1.2 (Little Endian Implicit)
  • 1.2.840.10008.1.2.1 (Little Endian Explicit)
  • 1.2.840.10008.1.2.2 (Explicit VR Big Endian)
  • 1.2.840.10008.1.2.4.50 (JPEG Baseline Process 1)
  • 1.2.840.10008.1.2.4.57 (JPEG Lossless)
  • 1.2.840.10008.1.2.4.70 (JPEG Lossless Selection Value 1)
  • 1.2.840.10008.1.2.4.90 (JPEG 2000 Lossless Only)
  • 1.2.840.10008.1.2.4.91 (JPEG 2000)
  • 1.2.840.10008.1.2.5 (RLE Lossless)

An unsupported transfer-syntax will result in 406 Not Acceptable.

Retrieve Metadata (for Study, Series, or Instance)

The following Accept header(s) are supported for retrieving metadata for a study, a series, or an instance:

  • application/dicom+json

Retrieving metadata will not return attributes with the following value representations:

VR Name Description
OB Other Byte
OD Other Double
OF Other Float
OL Other Long
OV Other 64-Bit Very Long
OW Other Word
UN Unknown

Retrieve Metadata Cache Validation (for Study, Series, or Instance)

Cache validation is supported using the ETag mechanism. In the response of a metadata reqeuest, ETag is returned as one of the headers. This ETag can be cached and added as If-None-Match header in the later requests for the same metadata. Two types of responses are possible if the data exists:

  • Data has not changed since the last request: HTTP 304 (Not Modified) response will be sent with no body.
  • Data has changed since the last request: HTTP 200 (OK) response will be sent with updated ETag. Required data will also be returned as part of the body.

Retrieve Rendered Image (For Instance or Frame)

The following Accept header(s) are supported for retrieving a rendered image an instance or a frame:

  • image/jpeg
  • image/png

In the case that no Accept header is specified the service will render an image/jpeg by default.

The service only supports rendering of a single frame. If rendering is requested for an instance with multiple frames then only the first frame will be rendered as an image by default.

When specifying a particular frame to return, frame indexing starts at 1.

The quality query parameter is also supported. An integer value between 1-100 inclusive (1 being worst quality, and 100 being best quality) may be passed as the value for the query paramater. This will only be used for images rendered as jpeg, and will be ignored for png render requests. If not specified will default to 100.

Retrieve Response Status Codes

Code Description
200 (OK) All requested data has been retrieved.
304 (Not Modified) The requested data has not modified since the last request. Content is not added to the response body in such case. Please see Retrieve Metadata Cache Validation (for Study, Series, or Instance) for more information.
400 (Bad Request) The request was badly formatted. For example, the provided study instance identifier did not conform the expected UID format or the requested transfer-syntax encoding is not supported.
401 (Unauthorized) The client is not authenticated.
403 (Forbidden) The user isn't authorized.
404 (Not Found) The specified DICOM resource could not be found or for rendered request the instance did not contain pixel data
406 (Not Acceptable) The specified Accept header is not supported or for rendered and transcode requests the file requested was too large
503 (Service Unavailable) The service is unavailable or busy. Please try again later.

Search (QIDO-RS)

Query based on ID for DICOM Objects (QIDO) enables you to search for studies, series and instances by attributes.

Method Path Description
Search for Studies
GET ../studies?... Search for studies
Search for Series
GET ../series?... Search for series
GET ../studies/{study}/series?... Search for series in a study
Search for Instances
GET ../instances?... Search for instances
GET ../studies/{study}/instances?... Search for instances in a study
GET ../studies/{study}/series/{series}/instances?... Search for instances in a series

The following Accept header(s) are supported for searching:

  • application/dicom+json

Supported Search Parameters

The following parameters for each query are supported:

Key Support Value(s) Allowed Count Description
{attributeID}= {value} 0...N Search for attribute/ value matching in query.
includefield= {attributeID}
all		 0...N The additional attributes to return in the response. Both, public and private tags are supported.
When all is provided, please see Search Response for more information about which attributes will be returned for each query type.
If a mixture of {attributeID} and 'all' is provided, the server will default to using 'all'.
limit= {value} 0..1 Integer value to limit the number of values returned in the response.
Value can be between the range 1 >= x <= 200. Defaulted to 100.
offset= {value} 0..1 Skip {value} results.
If an offset is provided larger than the number of search query results, a 204 (no content) response will be returned.
fuzzymatching= true | false 0..1 If true fuzzy matching is applied to PatientName attribute. It will do a prefix word match of any name part inside PatientName value. For example, if PatientName is "John^Doe", then "joh", "do", "jo do", "Doe" and "John Doe" will all match. However "ohn" will not match.

Searchable Attributes

We support searching on below attributes and search type.

Attribute Keyword All Studies All Series All Instances Study's Series Study's Instances Study Series' Instances
StudyInstanceUID X X X
PatientName X X X
PatientID X X X
PatientBirthDate X X X
AccessionNumber X X X
ReferringPhysicianName X X X
StudyDate X X X
StudyDescription X X X
ModalitiesInStudy X X X
SeriesInstanceUID X X X X
Modality X X X X
PerformedProcedureStepStartDate X X X X
ManufacturerModelName X X X X
SOPInstanceUID X X X

Search Matching

We support below matching types.

Search Type Supported Attribute Example
Range Query StudyDate, PatientBirthDate {attributeID}={value1}-{value2}. For date/ time values, we support an inclusive range on the tag. This will be mapped to attributeID >= {value1} AND attributeID <= {value2}. If {value1} is not specified, all occurrences of dates/times prior to and including {value2} will be matched. Likewise, if {value2} is not specified, all occurrences of {value1} and subsequent dates/times will be matched. However, one of these values has to be present. {attributeID}={value1}- and {attributeID}=-{value2} are valid, however, {attributeID}=- is invalid.
Exact Match All supported attributes {attributeID}={value1}
Fuzzy Match PatientName, ReferringPhysicianName Matches any component of the name which starts with the value.

Attribute ID

Tags can be encoded in a number of ways for the query parameter. We have partially implemented the standard as defined in PS3.18 6.7.1.1.1. The following encodings for a tag are supported:

Value Example
{group}{element} 0020000D
{dicomKeyword} StudyInstanceUID

Example query searching for instances: ../instances?Modality=CT&00280011=512&includefield=00280010&limit=5&offset=0

Search Response

The response will be an array of DICOM datasets. Depending on the resource, by default the following attributes are returned:

Default Study tags

Tag Attribute Name
(0008, 0005) SpecificCharacterSet
(0008, 0020) StudyDate
(0008, 0030) StudyTime
(0008, 0050) AccessionNumber
(0008, 0056) InstanceAvailability
(0009, 0090) ReferringPhysicianName
(0008, 0201) TimezoneOffsetFromUTC
(0010, 0010) PatientName
(0010, 0020) PatientID
(0010, 0030) PatientBirthDate
(0010, 0040) PatientSex
(0020, 0010) StudyID
(0020, 000D) StudyInstanceUID

Default Series tags

Tag Attribute Name
(0008, 0005) SpecificCharacterSet
(0008, 0060) Modality
(0008, 0201) TimezoneOffsetFromUTC
(0008, 103E) SeriesDescription
(0020, 000E) SeriesInstanceUID
(0040, 0244) PerformedProcedureStepStartDate
(0040, 0245) PerformedProcedureStepStartTime
(0040, 0275) RequestAttributesSequence

Default Instance tags

Tag Attribute Name
(0008, 0005) SpecificCharacterSet
(0008, 0016) SOPClassUID
(0008, 0018) SOPInstanceUID
(0008, 0056) InstanceAvailability
(0008, 0201) TimezoneOffsetFromUTC
(0020, 0013) InstanceNumber
(0028, 0010) Rows
(0028, 0011) Columns
(0028, 0100) BitsAllocated
(0028, 0008) NumberOfFrames

If includefield=all, below attributes are included along with default attributes. Along with default attributes, this is the full list of attributes supported at each resource level.

Additional Study tags

Tag Attribute Name
(0008, 1030) Study Description
(0008, 0063) AnatomicRegionsInStudyCodeSequence
(0008, 1032) ProcedureCodeSequence
(0008, 1060) NameOfPhysiciansReadingStudy
(0008, 1080) AdmittingDiagnosesDescription
(0008, 1110) ReferencedStudySequence
(0010, 1010) PatientAge
(0010, 1020) PatientSize
(0010, 1030) PatientWeight
(0010, 2180) Occupation
(0010, 21B0) AdditionalPatientHistory

Additional Series tags

Tag Attribute Name
(0020, 0011) SeriesNumber
(0020, 0060) Laterality
(0008, 0021) SeriesDate
(0008, 0031) SeriesTime

The following attributes are returned:

  • All the match query parameters and UIDs in the resource url.
  • IncludeField attributes supported at that resource level.
  • If the target resource is All Series, then Study level attributes are also returned.
  • If the target resource is All Instances, then Study and Series level attributes are also returned.
  • If the target resource is Study's Instances, then Series level attributes are also returned.
  • NumberOfStudyRelatedInstances aggregated attribute is supported in Study level includeField.
  • NumberOfSeriesRelatedInstances aggregated attribute is supported in Series level includeField.

Search Response Codes

The query API will return one of the following status codes in the response:

Code Description
200 (OK) The response payload contains all the matching resource.
204 (No Content) The search completed successfully but returned no results.
400 (Bad Request) The server was unable to perform the query because the query component was invalid. Response body contains details of the failure.
401 (Unauthorized) The client is not authenticated.
403 (Forbidden) The user isn't authorized.
503 (Service Unavailable) The service is unavailable or busy. Please try again later.

Additional Notes

  • Querying using the TimezoneOffsetFromUTC (00080201) is not supported.
  • The query API will not return 413 (request entity too large). If the requested query response limit is outside of the acceptable range, a bad request will be returned. Anything requested within the acceptable range, will be resolved.
  • When target resource is Study/Series there is a potential for inconsistent study/series level metadata across multiple instances. For example, two instances could have different patientName. In this case latest will win and you can search only on the latest data.
  • Paged results are optimized to return matched newest instance first, this may result in duplicate records in subsequent pages if newer data matching the query was added.
  • Matching is case in-sensitive and accent in-sensitive for PN VR types.
  • Matching is case in-sensitive and accent sensitive for other string VR types.
  • Only the first value will be indexed of a single valued data element that incorrectly has multiple values.

Delete

This transaction is not part of the official DICOMweb™ Standard. It uses the DELETE method to remove representations of Studies, Series, and Instances from the store.

Method Path Description
DELETE ../studies/{study} Delete all instances for a specific study.
DELETE ../studies/{study}/series/{series} Delete all instances for a specific series within a study.
DELETE ../studies/{study}/series/{series}/instances/{instance} Delete a specific instance within a series.

Parameters study, series and instance correspond to the DICOM attributes StudyInstanceUID, SeriesInstanceUID and SopInstanceUID respectively.

There are no restrictions on the request's Accept header, Content-Type header or body content.

Note: After a Delete transaction the deleted instances will not be recoverable.

Response Status Codes

Code Description
204 (No Content) When all the SOP instances have been deleted.
400 (Bad Request) The request was badly formatted.
401 (Unauthorized) The client is not authenticated.
401 (Unauthorized) The client isn't authenticated.
403 (Forbidden) The user isn't authorized.
404 (Not Found) When the specified series was not found within a study, or the specified instance was not found within the series.
503 (Service Unavailable) The service is unavailable or busy. Please try again later.

Delete Response Payload

The response body will be empty. The status code is the only useful information returned.

Worklist Service (UPS-RS)

The DICOM service supports the Push and Pull SOPs of the Worklist Service (UPS-RS). This service provides access to one Worklist containing Workitems, each of which represents a Unified Procedure Step (UPS).

Throughout, the variable {workitem} in a URI template stands for a Workitem UID.

Create Workitem

This transaction uses the POST method to create a new Workitem.

Method Path Description
POST ../workitems Create a Workitem.
POST ../workitems?{workitem} Creates a Workitem with the specified UID.

If not specified in the URI, the payload dataset must contain the Workitem in the SOPInstanceUID attribute.

The Accept and Content-Type headers are required in the request, and must both have the value application/dicom+json.

There are a number of requirements related to DICOM data attributes in the context of a specific transaction. Attributes may be required to be present, required to not be present, required to be empty, or required to not be empty. These requirements can be found in this table.

Notes on dataset attributes:

  • SOP Instance UID: Although the reference table above says that SOP Instance UID should not be present, this guidance is specific to the DIMSE protocol and is handled diferently in DICOMWeb™. SOP Instance UID should be present in the dataset if not in the URI.
  • Conditional requirement codes: All the conditional requirement codes including 1C and 2C are treated as optional.

Create Response Status Codes

Code Description
201 (Created) The target Workitem was successfully created.
400 (Bad Request) There was a problem with the request. For example, the request payload did not satisfy the requirements above.
401 (Unauthorized) The client is not authenticated.
403 (Forbidden) The user isn't authorized.
409 (Conflict) The Workitem already exists.
415 (Unsupported Media Type) The provided Content-Type is not supported.
503 (Service Unavailable) The service is unavailable or busy. Please try again later.

Create Response Payload

A success response will have no payload. The Location and Content-Location response headers will contain a URI reference to the created Workitem.

A failure response payload will contain a message describing the failure.

Request Cancellation

This transaction enables the user to request cancellation of a non-owned Workitem.

There are four valid Workitem states:

  • SCHEDULED
  • IN PROGRESS
  • CANCELED
  • COMPLETED

This transaction will only succeed against Workitems in the SCHEDULED state. Any user can claim ownership of a Workitem by setting its Transaction UID and changing its state to IN PROGRESS. From then on, a user can only modify the Workitem by providing the correct Transaction UID. While UPS defines Watch and Event SOP classes that allow cancellation requests and other events to be forwarded, this DICOM service does not implement these classes, and so cancellation requests on workitems that are IN PROGRESS will return failure. An owned Workitem can be canceled via the Change Workitem State transaction.

Method Path Description
POST ../workitems/{workitem}/cancelrequest Request the cancellation of a scheduled Workitem

The Content-Type headers is required, and must have the value application/dicom+json.

The request payload may include Action Information as defined in the DICOM Standard.

Request Cancellation Response Status Codes

Code Description
202 (Accepted) The request was accepted by the server, but the Target Workitem state has not necessarily changed yet.
400 (Bad Request) There was a problem with the syntax of the request.
401 (Unauthorized) The client is not authenticated.
403 (Forbidden) The user isn't authorized.
404 (Not Found) The Target Workitem was not found.
409 (Conflict) The request is inconsistent with the current state of the Target Workitem. For example, the Target Workitem is in the SCHEDULED or COMPLETED state.
415 (Unsupported Media Type) The provided Content-Type is not supported.
503 (Service Unavailable) The service is unavailable or busy. Please try again later.

Request Cancellation Response Payload

A success response will have no payload, and a failure response payload will contain a message describing the failure. If the Workitem Instance is already in a canceled state, the response will include the following HTTP Warning header: 299: The UPS is already in the requested state of CANCELED.

Retrieve Workitem

This transaction retrieves a Workitem. It corresponds to the UPS DIMSE N-GET operation.

Refer: https://dicom.nema.org/medical/dicom/current/output/html/part18.html#sect_11.5

If the Workitem exists on the origin server, the Workitem shall be returned in an Acceptable Media Type. The returned Workitem shall not contain the Transaction UID (0008,1195) Attribute. This is necessary to preserve this Attribute's role as an access lock.

Method Path Description
GET ../workitems/{workitem} Request to retrieve a Workitem

The Accept header is required, and must have the value application/dicom+json.

Retrieve Workitem Response Status Codes

Code Description
200 (OK) Workitem Instance was successfully retrieved.
400 (Bad Request) There was a problem with the request.
401 (Unauthorized) The client is not authenticated.
403 (Forbidden) The user isn't authorized.
404 (Not Found) The Target Workitem was not found.
503 (Service Unavailable) The service is unavailable or busy. Please try again later.

Retrieve Workitem Response Payload

  • A success response has a single part payload containing the requested Workitem in the Selected Media Type.
  • The returned Workitem shall not contain the Transaction UID (0008,1195) Attribute of the Workitem, since that should only be known to the Owner.

Update Workitem

This transaction modifies attributes of an existing Workitem. It corresponds to the UPS DIMSE N-SET operation.

Refer: https://dicom.nema.org/medical/dicom/current/output/html/part18.html#sect_11.6

To update a Workitem currently in the SCHEDULED state, the Transaction UID Attribute shall not be present. For a Workitem in the IN PROGRESS state, the request must include the current Transaction UID as a query parameter. If the Workitem is already in the COMPLETED or CANCELED states, the response will be 400 (Bad Request).

Method Path Description
POST ../workitems/{workitem}?{transaction-uid} Update Workitem Transaction

The Content-Type header is required, and must have the value application/dicom+json.

The request payload contains a dataset with the changes to be applied to the target Workitem. When modifying a sequence, the request must include all Items in the sequence, not just the Items to be modified. When multiple Attributes need updating as a group, do this as multiple Attributes in a single request, not as multiple requests.

There are a number of requirements related to DICOM data attributes in the context of a specific transaction. Attributes may be required to be present, required to not be present, required to be empty, or required to not be empty. These requirements can be found in this table.

Notes on dataset attributes:

  • Conditional requirement codes: All the conditional requirement codes including 1C and 2C are treated as optional.

The request cannot set the value of the Procedure Step State (0074,1000) Attribute. Procedure Step State is managed using the Change State transaction, or the Request Cancellation transaction.

Update Workitem Transaction Response Status Codes

Code Description
200 (OK) The Target Workitem was updated.
400 (Bad Request) There was a problem with the request. For example: (1) the Target Workitem was in the COMPLETED or CANCELED state. (2) the Transaction UID is missing. (3) the Transaction UID is incorrect. (4) the dataset did not conform to the requirements.
401 (Unauthorized) The client is not authenticated.
403 (Forbidden) The user isn't authorized.
404 (Not Found) The Target Workitem was not found.
409 (Conflict) The request is inconsistent with the current state of the Target Workitem.
415 (Unsupported Media Type) The provided Content-Type is not supported.
503 (Service Unavailable) The service is unavailable or busy. Please try again later.

Update Workitem Transaction Response Payload

The origin server shall support header fields as required in Table 11.6.3-2.

A success response shall have either no payload, or a payload containing a Status Report document.

A failure response payload may contain a Status Report describing any failures, warnings, or other useful information.

Change Workitem State

This transaction is used to change the state of a Workitem. It corresponds to the UPS DIMSE N-ACTION operation "Change UPS State". State changes are used to claim ownership, complete, or cancel a Workitem.

Refer: https://dicom.nema.org/medical/dicom/current/output/html/part18.html#sect_11.7

If the Workitem exists on the origin server, the Workitem shall be returned in an Acceptable Media Type. The returned Workitem shall not contain the Transaction UID (0008,1195) Attribute. This is necessary to preserve this Attribute's role as an access lock as described here.

Method Path Description
PUT ../workitems/{workitem}/state Change Workitem State

The Accept header is required, and must have the value application/dicom+json.

The request payload shall contain the Change UPS State Data Elements. These data elements are:

  • Transaction UID (0008,1195) The request payload shall include a Transaction UID. The user agent creates the Transaction UID when requesting a transition to the IN PROGRESS state for a given Workitem. The user agent provides that Transaction UID in subsequent transactions with that Workitem.

  • Procedure Step State (0074,1000) The legal values correspond to the requested state transition. They are: "IN PROGRESS", "COMPLETED", or "CANCELED".

Change Workitem State Response Status Codes

Code Description
200 (OK) Workitem Instance was successfully retrieved.
400 (Bad Request) The request cannot be performed for one of the following reasons: (1) the request is invalid given the current state of the Target Workitem. (2) the Transaction UID is missing. (3) the Transaction UID is incorrect
401 (Unauthorized) The client is not authenticated.
403 (Forbidden) The user isn't authorized.
404 (Not Found) The Target Workitem was not found.
409 (Conflict) The request is inconsistent with the current state of the Target Workitem.
503 (Service Unavailable) The service is unavailable or busy. Please try again later.

Change Workitem State Response Payload

  • Responses will include the header fields specified in section 11.7.3.2
  • A success response shall have no payload.
  • A failure response payload may contain a Status Report describing any failures, warnings, or other useful information.

Search Workitems

This transaction enables you to search for Workitems by attributes.

Method Path Description
GET ../workitems? Search for Workitems

The following Accept header(s) are supported for searching:

  • application/dicom+json

Supported Search Parameters

The following parameters for each query are supported:

Key Support Value(s) Allowed Count Description
{attributeID}= {value} 0...N Search for attribute/ value matching in query.
includefield= {attributeID}
all		 0...N The additional attributes to return in the response. Only top-level attributes can be specified to be included - not attributes that are part of sequences. Both public and private tags are supported.
When all is provided, please see Search Response for more information about which attributes will be returned for each query type.
If a mixture of {attributeID} and 'all' is provided, the server will default to using 'all'.
limit= {value} 0...1 Integer value to limit the number of values returned in the response.
Value can be between the range 1 >= x <= 200. Defaulted to 100.
offset= {value} 0...1 Skip {value} results.
If an offset is provided larger than the number of search query results, a 204 (no content) response will be returned.
fuzzymatching= true | false 0...1 If true fuzzy matching is applied to any attributes with the Person Name (PN) Value Representation (VR). It will do a prefix word match of any name part inside these attributes. For example, if PatientName is "John^Doe", then "joh", "do", "jo do", "Doe" and "John Doe" will all match. However "ohn" will not match.

Searchable Attributes

We support searching on these attributes:

Attribute Keyword
PatientName
PatientID
ReferencedRequestSequence.AccessionNumber
ReferencedRequestSequence.RequestedProcedureID
ScheduledProcedureStepStartDateTime
ScheduledStationNameCodeSequence.CodeValue
ScheduledStationClassCodeSequence.CodeValue
ScheduledStationGeographicLocationCodeSequence.CodeValue
ProcedureStepState
StudyInstanceUID

Search Matching

We support these matching types:

Search Type Supported Attribute Example
Range Query Scheduled​Procedure​Step​Start​Date​Time {attributeID}={value1}-{value2}. For date/ time values, we support an inclusive range on the tag. This will be mapped to attributeID >= {value1} AND attributeID <= {value2}. If {value1} is not specified, all occurrences of dates/times prior to and including {value2} will be matched. Likewise, if {value2} is not specified, all occurrences of {value1} and subsequent dates/times will be matched. However, one of these values has to be present. {attributeID}={value1}- and {attributeID}=-{value2} are valid, however, {attributeID}=- is invalid.
Exact Match All supported attributes {attributeID}={value1}
Fuzzy Match PatientName Matches any component of the name which starts with the value.

Note: While we do not support full sequence matching, we do support exact match on the attributes listed above that are contained in a sequence.

Attribute ID

Tags can be encoded in a number of ways for the query parameter. We have partially implemented the standard as defined in PS3.18 6.7.1.1.1. The following encodings for a tag are supported:

Value Example
{group}{element} 00100010
{dicomKeyword} PatientName

Example query: ../workitems?PatientID=K123&0040A370.00080050=1423JS&includefield=00404005&limit=5&offset=0

Search Response

The response will be an array of 0...N DICOM datasets. The following attributes are returned:

  • All attributes in DICOM PS 3.4 Table CC.2.5-3 with a Return Key Type of 1 or 2.
  • All attributes in DICOM PS 3.4 Table CC.2.5-3 with a Return Key Type of 1C for which the conditional requirements are met.
  • All other Workitem attributes passed as match parameters.
  • All other Workitem attributes passed as includefield parameter values.

Search Response Codes

The query API will return one of the following status codes in the response:

Code Description
200 (OK) The response payload contains all the matching resource.
206 (Partial Content) The response payload contains only some of the search results, and the rest can be requested through the appropriate request.
204 (No Content) The search completed successfully but returned no results.
400 (Bad Request) The was a problem with the request. For example, invalid Query Parameter syntax. Response body contains details of the failure.
401 (Unauthorized) The client is not authenticated.
403 (Forbidden) The user isn't authorized.
503 (Service Unavailable) The service is unavailable or busy. Please try again later.

Additional Notes

  • The query API will not return 413 (request entity too large). If the requested query response limit is outside of the acceptable range, a bad request will be returned. Anything requested within the acceptable range, will be resolved.
  • Paged results are optimized to return matched newest instance first, this may result in duplicate records in subsequent pages if newer data matching the query was added.
  • Matching is case insensitive and accent insensitive for PN VR types.
  • Matching is case insensitive and accent sensitive for other string VR types.
  • If there is a scenario where canceling a Workitem and querying the same happens at the same time, then the query will most likely exclude the Workitem that is getting updated and the response code will be 206 (Partial Content).