DICOM

Background |  Areas of Current Investigation

Background

Digital Imaging and Communications in Medicine (DICOM) is a clinical messaging syntax used to exchange medical images between medical equipment and information systems. The DICOM standard was created by the National Electrical Manufacturers Association (NEMA) to aid in the distribution, storage, and viewing of medical images, such as computed tomography and magnetic resonance imaging scans and ultrasound.  DICOM enables the integration of scanners, servers, workstations, printers, and network hardware from multiple manufacturers into a picture archiving and communication system (PACS).

A practical example is the transmission of x-ray images to an electronic health record (EHR). The ability of the sender and the receiver to mutually use the DICOM standard allows this transmission to succeed.

The different devices come with DICOM conformance statements that clearly state the DICOM classes they support. DICOM models the image acquisition process and information objects related to imaging, and it specifies how the image data, the metadata, and related objects are represented in a binary format.

DICOM has been the global standard for medical image information since the 1980s. It is pervasive throughout the medical imaging community, and nearly every medical imaging device supports some aspect of the standard. DICOM has been widely adopted by hospitals and is making inroads in smaller applications like dentists' and doctors' offices.

DICOM is an independent, international standards development organization administered by NEMA's Medical Imaging and Technology Alliance. More information on DICOM can be found on the NEMA Web site.

Areas of Current Investigation

Despite its pervasiveness, size, and complexity, DICOM lacks a reference information model of the imaging domain. A reference information model is a formal description of a domain that enables users to share consistent meaning and establish semantic interoperability beyond a local context.

Researchers Zhau and Lee developed a methodology to transform programmatically structured reporting (SR) templates defined by the DICOM standard into an XML schema representation to promote common formats for specific reporting applications or domains.

Some current research based on DICOM has focused on designing structured reporting modules corresponding to the specifications from the Content Mapping Resource section of the DICOM standard, which defines the structure of the DICOM medical reports and their composing elements: coded concepts, context groups, and templates.

An information model of imaging based on DICOM is needed to enable the community to create intelligent, imaging-based applications that are interoperable. The Stanford Center for Biomedical Informatics Research is developing the DICOM Ontology (DO), an ontology that will be a single common reference information model for the imaging domain. The DO will be analogous to the Gene Ontology (GO) and serve a role in radiology similar to that which GO serves in biology. The DO will unify and make explicit all the key entities and relations in DICOM in a user friendly and machine-processable format. The DO will ultimately become a reference ontology--one that comprehensively represents knowledge about the medical imaging domain independent from specificobjectives or applications, guided by a theory of the imaging domain and by robust ontology design principles that encourage reuse.