Time has come for DICOM to accommodate MR advances

February 6, 2001

Given major improvements in MR, it seems appropriate to reconsider the content of the MR information object defined by the DICOM committee in the early 1990s and to address new technologies using a more flexible interface. Some users, for example, have

Given major improvements in MR, it seems appropriate to reconsider the content of the MR information object defined by the DICOM committee in the early 1990s and to address new technologies using a more flexible interface.

Some users, for example, have an interest in the raw data making up acquired images. They like to export this information and process it at dedicated MR workstations. Other users would like to see the spectroscopy data as well because these can reveal information not necessarily obvious from the reconstructed images.

The variety of image processing and acquisition techniques has expanded as well. It is now possible to change parameters on the fly during acquisition and get information based on different physical characteristics. Initially, the only dimensions available for acquired images were time and physical location. The number of dimensions has become almost infinite when all acquisition possibilities are taken into account.

The DICOM working group is focusing on an extension of the MR object definition to accommodate these and other developments. This is important from a user perspective for several reasons:
- First, it will eliminate the need for the private exchange of diagnostic information such as spectroscopic data by allowing these data to be properly stored and displayed on other vendors' workstations (one caveat: You have to make sure the system supports the new DICOM SOP Class, information available in the DICOM conformance statement).
- MR object definition extensions will enable the exchange of spectroscopic and raw data, not just image data.
- Image data will no longer be exchanged as individual images but as multiframe images. It is easy to package all pixel data of a full image acquisition, such as a cine loop, into a single folder. The trick is how to describe the differences between the individual frames of the multiframe object. The DICOM committee has overcome this problem by developing a convenient description of all data dimensions.

Final approval of the proposed MR DICOM extension is expected this summer. In the meantime, the proposed changes are available for public comment. Interested parties can get a copy of the proposal from the NEMA website (www.nema.org).

People sometimes ask me when the DICOM standard will finally be done. The answer is that as long as the modalities keep evolving, a need to accommodate these changes will always exist. Vendors will always have to add new features and changes to their interfaces, and users will continue to upgrade their equipment. Good news or bad news? Well, progress requires a certain effort.

Questions/concerns: herman@otechimg.com or visit our Web site at http://www.otechimg.com

From the Feb. 6 Health Networking News, a biweekly business newsletter covering the medical information technology industry published by Diagnostic Imaging.