Peter M. Kuzmak, MS, US Department of Veteran Affairs; Andrew E. Casertano, MSE; Ruth E. Dayhoff, MD

One of the outstanding unsolved problems in medical imaging is how to efficiently import unordered DICOM studies from outside facilities into the local institution’s electronic medical record (EMR) systems, that is, the hospital information system (HIS), radiology information system (RIS), and picture archiving and communications system (PACS). We will demonstrate one possible way to address the problem of importing unordered DICOM objects from outside facilities, and also provide some insight as to how to transfer reports.

DICOM images that originate outside the Department of Veterans Affairs (VA) must be incorporated into the VA EMR. When outside images are inserted into the VA EMR, they are properly indexed and are fully accessible to the VA VistA Imaging applications, just as if they came from a local modality. They can be used as reference images and can be displayed anywhere in the 157 medical center VA healthcare enterprise.

If the outside image were just “loaded” into a VA PACS without being incorporated into the VA EMR, the images would not be properly indexed and would have very limited accessibility.

The problem of importing unordered DICOM studies became much more important with the increase of casualities from the Iraq and Afghanistan wars. Critically wounded warriors are transferred from Department of Defense (DoD) hospitals to VA medical centers. In order to provide continuity of care, it is necessary to transfer those patients’ DICOM images as well, and insert them into the VA EMR. This process can involve over 100 studies per patient. With current technology, importing unordered imaging studies from the outside into the VA EMR has been a laborious, inefficient, manual process: estimates ranging from 7 to 40 minutes to import a single study.

The need to import the DICOM images for our most seriously wounded patients forced us to develop a more efficient automated workflow.

The general problem we are addressing is how to import unordered DICOM studies performed at outside facilities into the local institution’s EMR systems. These studies may arrive on DICOM-formatted media or may be transmitted directly over a network. A key use case is the patient who presents with image data on an Integrating the Healthcare Enterprise (IHE) Portable Data for Imaging (PDI) compatible media.[1]

The IHE Import Reconciliation Workflow (IRWF) integration profile specifies the technique for importing DICOM objects for ordered studies.[2] With the IRWF, patient and study identification information is obtained from the study initially ordered on the local system and then used to replace the values of the corresponding data elements in the DICOM objects that are to be imported. To provide an audit trail, the original DICOM values, along with the import application, attributes are saved elsewhere in the DICOM header. The outside study’s DICOM objects, now with local patient and study identification, are then imported and associated with the initially ordered study.

When IRWF is used for importing unordered studies, it is first necessary to provide correct identification of the patient in the receiving system. Then a corresponding equivalent study must be created in the local institution EMR systems for each unordered outside study that is to be imported. The patient and study identification information for the newly created local study is used to update the outside study’s DICOM objects. Then importation takes place and the outside study’s DICOM objects are associated with the newly created study on the local EMR systems.

Original Manual Import Process

The original import process was done on a study-by-study basis. The user picked a study to be imported, and manually created the corresponding equivalent study on the local EMR systems. The user then had to manually match the outside study to the newly created one, start the import process, and wait for completion before proceeding to import the next study.

Automated Import Process

The workflow was redesigned to take advantage of automation and reduce the manual effort for greater efficiency. User activity was greatly simplified while user wait time was reduced to a minimum. All of the manual steps necessary to import a set of studies are performed first. Then the automated import reconciliation for the entire set of studies is performed. The workflow handles the importing of both unordered and ordered outside studies.

Automated Import Process for Unordered Studies

The user selects the unordered outside study to be imported and reviews the study and series information and images (if necessary). The user then specifies the local radiology procedure and modifier(s) that most closely match what was performed, and identifies the patient from the local HIS. The user repeats this process for each outside study that is to be imported.

After the user assigns patient identifiers, equivalent procedure, and modifier(s) to each unordered study to be imported, the rest of the import reconciliation workflow is performed automatically. The corresponding equivalent radiology studies are automatically created on the local EMR systems. Each new study is created with the same study date and time as the originally performed study, so that the chronological study sequence information is properly maintained. The patient and study identification information from each newly created study is used to update the DICOM objects for corresponding outside study. The DICOM objects with the new patient and study identification information are then collectively imported and associated with the newly created studies.

Automated Import Process for Ordered Studies

The same user interaction is used for importing an ordered study, except that a Modality Worklist query is used to find the initially ordered study in the local EMR systems. The patient and study identification information from that study is then used to update the imported DICOM objects. The DICOM objects with the initial local patient and study identification information are then imported and associated with the initially ordered study.

Extensive internal testing indicates the manual time to import an unordered study will be less than one minute. This represents a significant time savings. This application is planned to be deployed to VA medical centers starting in late 2008.

Importing unordered studies is becoming an increasingly important requirement as PACS proliferate. We were co-authors of the original IHE IRWF, and now think some of the ideas that we have implemented could be incorporated into future versions of IRWF to handle the unordered study use case.

We also believe, if reports were exported to portable media in DICOM format along with images, they could be imported the same way as the images. If reports were transferred as DICOM Encapsulated PDF objects, they could be displayed in a consistent format across different vendor systems. DICOM SR objects could be transferred to provide discrete data, but their display format depends on the capabilities of the local EMR systems, which vary between implementations. DICOM Encapsulated PDF and DICOM SR are complementary and serve different needs. Just as with the “For Presentation” and “For Processing” SOP Classes, both are necessary.

Building on IHE PDI and IRWF, we have shown it possible to import unordered outside studies in an efficient manner. This capability is very important in providing patient care, especially when dealing with a mobile patient population.

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