System integration, between DICOM compatible devices as well as DICOM and HL7 compliant devices, is critical to accommodate efficient and effective workflow. Interface issues could surface, especially on the boundary between DICOM and HL7, due to the differences between both standards.
Some modality equipments use a gateway or interface box to achieve DICOM compatibility. Typically, they do not support DICOM but have another proprietary communication protocol that they use internally to communicate among devices of the same vendor. A separate translator, in the form of an interface box, is needed to get a true DICOM output.
These boxes have several disadvantages over the native DICOM connection. Often, information present in the proprietary protocol cannot be easily translated into DICOM. In addition, there could be information that is required by the DICOM standard that is not available as part of the proprietary protocol. Therefore, it has to be made up by the translator box. This causes problems when this missing information is needed to perform certain functions or run certain applications at, for example, a workstation. Some of the problems are:
Sophisticated applications, such as 3D reconstruction, are often not possible using images that are converted with an interface box.
Functions such as displaying slice lines on the scout views
images are often not available.
The error handling is almost always inadequate. For example, if the receiving device cannot accept any more images because its hard drive is full, it communicates a DICOM error to the interface box.
Translating these error conditions and reporting them back to the operator at the originating modality through the interface box is almost always insufficient and sometimes not present at all.
Gateways are considered a necessary evil, because some devices simply do not have the capability to support a standard communication board and/or an operating system to support the TCP/IP communication protocol.