Proc. SPIE. 9039, Medical Imaging 2014: PACS and Imaging Informatics: Next Generation and Innovations
KEYWORDS: Data modeling, Databases, Stereoscopy, Magnetic resonance imaging, Computer science, Medical imaging, Data acquisition, Computed tomography, Radiology, Picture Archiving and Communication System
Most medical images are archived and transmitted using the DICOM format. The DICOM information model combines image pixel data and associated metadata into a single object. It is not possible to access the metadata separately from the pixel data. However, there are important use cases that only need access to metadata, and the DICOM format increases the running time of those use cases. Tag morphing is an example of one such use case. Tag or attribute morphing includes insertion, deletion, or modification of one or more of the metadata attributes in a study. It is typically used for order reconciliation on study acquisition or to localize the Issuer of Patient ID and the Patient ID attributes when data from one Medical Record Number (MRN) domain is transferred to or displayed in a different domain. This work uses the Multi-Series DICOM (MSD) format to reduce the time required for tag morphing. The MSD format separates metadata from pixel data, and at the same time eliminates duplicate attributes. MSD stores studies using two files rather than in many single frame files typical of DICOM. The first file contains the de-duplicated study metadata, and the second contains pixel data and other bulkdata. A set of experiments were performed where metadata updates were applied to a set of DICOM studies stored in both the traditional Single Frame DICOM (SFD) format and the MSD format. The time required to perform the updates was recorded for each format. The results show that tag morphing is, on average, more than eight times faster in MSD format.
Proc. SPIE. 8674, Medical Imaging 2013: Advanced PACS-based Imaging Informatics and Therapeutic Applications
KEYWORDS: Image compression, Receivers, Computer science, Medical imaging, Image transmission, Image enhancement, Local area networks, Radiology, Algorithm development, Picture Archiving and Communication System
The DICOM standard defines the application layer network protocol used to send and receive medical images. DICOM is defined on top of TCP. DICOM addresses many issues associated with medical image transmission; however, sending and receiving large studies is inefficient because they are transmitted one object at a time. The Multi-Series DICOM (MSD) format has been introduced as a solution to this problem. It can store an entire study in a single object. In addition, the metadata information in the MSD object is free of repetition. In this work, the performance of sending and receiving DICOM studies as MSD objects is investigated. A set of DICOM studies is stored in two formats, traditional Single-Frame DICOM (SFD) and MSD. The times required to send the studies in both formats synchronously and asynchronously are measured. The results show that there is a significant reduction in the time required to synchronously send the studies in the MSD format compared to the SFD format and a small improvement when sending asynchronously. Sending studies synchronously in the SFD format results in a delay waiting for the acknowledgement for each DICOM object sent before sending subsequent ones. With the asynchronous approach, the time reduction is a direct result of the difference in metadata size between the SFD and MSD formats and the lower number of acknowledgements sent back from the receiving application entity to the sender. The results show that it is more efficient to send DICOM studies as MSD objects whether synchronously or asynchronously.