Standards Update: New DICOM extension eases workflow between disparate systems

July 12, 2000

Standards Update: New DICOM extension eases workflow between disparate systemsBy Herman Oosterwijk, president, OTech Inc.Not long ago, I visited a site that had a

Standards Update:
New DICOM extension eases workflow between disparate systems

By Herman Oosterwijk, president, OTech Inc.

Not long ago, I visited a site that had a medium-sized PACS installation from a major vendor. Several radiologists were reading images using workstations from a common pool of exams. I noticed another workstation, from a different vendor, that was switched off and pushed out of the way in a corner, and I asked why no one was using it. I was told that they would love to utilize that particular workstation because of its superior user friendliness and features, but that it was not possible because it had no workflow support.

To understand the problem, one needs to study more carefully how the actual communication between workstations and a PACS archive is implemented. When a radiologist retrieves a certain study, a signal is sent back to the image manager/archive to lock that study and indicate its unavailability to other radiologists so that there are no double reads. When reporting is completed, this will be indicated as well.

The problem is that the exchange of this status information between workstations and an image manager/archive from a particular vendor is done in a proprietary manner. A workstation from another vendor does not have access to that type of information. It can display a list of recent images, but information on whether they are being read by another radiologist or have been reported on is not available. The result is that third-party workstations are still locked out by most major PACS vendors.

A new DICOM extension provides a solution. It formalizes the exchange between workstations and an archive in a standard manner so that when a particular vendor supports this extension, other workstations can have access to the workflow data; i.e., the read “lock” and “ready” information.

The structure is very similar to the DICOM Modality Worklist and Modality Performed Procedure Step services, which provide worklist and status information to a modality about what exams are scheduled and what scheduled exams are performed.

The new extension takes this one step further by also providing a locking mechanism and a scheduler to provide information about the exams to be read. A physician can request a list of exams to be read, issue a command to lock it, and, when completed, update the status. In addition, results such as reports or images (in the case of a postprocessing workstation) can be specified. Implementing these services will loosen the tight connection that currently exists between viewing stations and the image manager/archive of the same vendor.

Third-party workstation vendors will likely begin implementing these new services as soon as they are standardized, which should happen before the end of this year. This is another example of how DICOM is extending beyond basic image communication into image and workflow management and creating a more open environment.