DICOM PS3.18 2020b - Web Services

7.2 Resources, Representations, and Target URIs

In RESTful Web Services, a resource is an abstract object with a type, associated data, relationships to other resources,and a set of methods that operate on it. Resources are grouped into collections. Collections are themselves resources as well. Each collection is unordered and contains only one type of resource. Collections can exist globally, at the top level of an API, but can also be contained inside a resource. In the latter case, we refer to these collections as sub-collections. Sub-collections usually express some kind of "contained in" relationship.

7.2.1 DICOM Restful Resources

The DICOM Resources defined in this Part of the Standard are typically either a DICOM Web Services or DICOM Information Objects. Examples include Studies, Series, Instances, Worklists, and Workitems.

DICOM Resources are grouped into collections and hierarchies. The following resources are examples of collections:

Resource Path



A collection of Studies.


A collection of Series.


A collection of Instance.


A sequence of Frames.

The following resources are examples of hierarchies:


Contains a collection of Series.


Contains a collection of Instances.


Contains a sequence of frames.

A DICOM Web Service origin server manages a collection of resources. This might not be done directly; for example, an origin server could act as a proxy, converting RESTful requests into DIMSE requests, and DIMSE responses into RESTful responses.

Resources are typically created and/or accessed by user agents.

DICOM PS3.18 2020b - Web Services