Interoperability for image and non-image data in the DICOM standard investigated from different vendor implementations

DICOM conformity alone does not guarantee the interoperability of imaging equipment developed by different parties. In a survey, the DICOM data sets of 19 complete angiographic examinations have bean compared. It was found that most data sets are DICOM-compliant and that the image data are encoded in a similar way. On the other hand, the interoperability of non-image data has been found to be very limited. In particular, data concerning patient demographics, time synchronization, the contrast agent and image acquisition information are missing or encoded in different ways. The reasons for this were misinterpretations by manufacturers and ambiguous definitions in the DICOM standard. Furthermore, it was realized that incorrect encoding could often not be found by automatic validation tools: In contrast, manual examination and expert knowledge are necessary in order to understand problems in interoperability.