The wholesale move to digital imaging and the on-going adoption of PACS technology in radiology has allowed institutions to move from film and lightbox interpretation to computer workstation viewing and reporting. For academic facilities, this has necessitated the implementation of digital teaching files to support the education of residents and staff in on-line interpretation.

A team from the department of medical imaging at St. Vincent’s Hospital in Victoria, Australia, has integrated a digital teaching file with its PACS (GE Healthcare Centricity). The implementation of this tool, according to a recent article published in the Journal of Digital Imaging, did not incur any additional hardware or software costs.

The digital teaching file developers set out to create a solution that could easily be used by clinicians, had a simple submission process, could support multiple users, and would be searchable on all data fields. They designed it to take advantage of two aspects of their institution’s PACS.

“These aspects are: (1) the DICOM database structure on QA (quality assurance) work stations is compatible with standard Microsoft Access databases, and (2) the web server used for distributing the image data to the hospital supports an open application programming interface (API),” they wrote.

The DICOM database on the QA station can be exported and edited via Microsoft, which allows creation of a teaching file database that contains relational tables for the teaching files, which is considered the back-end of the system. The front-end of the system is a teaching file component interface that contains all the appropriate display forms and database query structures that is utilized by its users.

“The physical size of the user interface application is less than 1 megabyte (848 kB) and the physical size of the back-end database is currently 3.4 MB for a database holding all the relevant demographic data for 1,559 cases,” the developers stated.

Submission of cases for teaching file consideration is done by performing a DICOM send to the QA workstation, which can be accomplished by any radiologist’s workstation on the PACS. The cases are maintained in a separate staging area on the QA workstation until they are completed and submitted to the teaching file.

The teaching file component has no data tables; it is a graphical user interface comprised of multiple forms that are linked both to the teaching file back-end and to the DICOM database of the QA workstation, according to the developers.

“The user interface is used to complete cases that are awaiting submission, to interrogate the teaching file, and to facilitate display of image data from the teaching file,” the authors wrote.

By taking advantage of the API functionality of the PACS, the developers were able to create a teaching file design that accesses the PACS for images.

“By creating hypertext links within the teaching file application that pass on an appropriately constructed command string, a fully integrated image link can be constructed,” the authors wrote. “The image data being displayed via the PACS web server is at the full bit-depth as acquired, and the technology being used to display it is exactly the same as what is used throughout the hospital for clinical display.”

The developers chose this strategy because it did not require the radiologists to create JPEG or TIFF images from the original DICOM files; it allows access to the full patient imaging history; and it was easier to implement than a standalone DICOM viewer for the teaching files.

“A unique benefit of this teaching file over any other reported is that even though the file does not directly contain images, the use of the open API connection to the PACS web server gives unprecedented access to image data not normally encountered in a teaching file,” the authors noted.