Introduction (DICOM)

 
The word DICOM is an abbreviation for:

Digital Imaging and Communication in Medicine.

The most appropriate source of information about the DICOM standard is the official homepage of DICOM:

http://medical.nema.org/

The DICOM standard was envisioned, formulated, is owned and managed by NEMA, the National Electrical Manufacturers Association of the United States.

DICOM (Digital Imaging and Communications in Medicine) is a standard for handling, storing, printing, and transmitting information in medical imaging. It includes a file format definition and a network communications protocol – as Wikipedia defines the standard.

To fully understand the nature of the standard it is worth wile to read NEMA’s disclaimer attached to the standard:

„The information in this publication was considered technically sound by the consensus of persons engaged in the development and approval of the document at the time it was developed. Consensus does not necessarily mean that there is unanimous agreement among every person participating in the development of this document. NEMA standards and guideline publications, of which the document contained herein is one, are developed through a voluntary consensus standards development process. This process brings together volunteers and/or seeks out the views of persons who have an interest in the topic covered by this publication. While NEMA administers the process and establishes rules to promote fairness in the development of consensus, it does not write the document and it does not independently test, evaluate, or verify the accuracy or completeness of any information or the soundness of any judgments contained in its standards and guideline publications. NEMA disclaims liability for any personal injury, property, or other damages of any nature whatsoever, whether special, indirect, consequential, or compensatory, directly or indirectly resulting from the publication, use of, application, or reliance on this document. NEMA disclaims and makes no guaranty or warranty, expressed or implied, as to the accuracy or completeness of any information published herein, and disclaims and makes no warranty that the information in this document will fulfill any of your particular purposes or needs. NEMA does not undertake to guarantee the performance of any individual manufacturer or seller’s products or services by virtue of this standard or guide. In publishing and making this document available, NEMA is not undertaking to render professional or other services for or on behalf of any person or entity, nor is NEMA undertaking to perform any duty owed by any person or entity to someone else. Anyone using this document should rely on his or her own independent judgment or, as appropriate, seek the advice of a competent professional in determining the exercise of reasonable care in any given circumstances. Information and other standards on the topic covered by this publication may be available from other sources, which the user may wish to consult for additional views or information not covered by this publication. NEMA has no power, nor does it undertake to police or enforce compliance with the contents of this document. NEMA does not certify, test, or inspect products, designs, or installations for safety or health purposes. Any certification or other statement of compliance with any health or safety–related information in this document shall not be attributable to NEMA and is solely the responsibility of the certifier or maker of the statement.”

Even if NEMA rejects full responsibility, DICOM is one of the most efficient de facto standards ever envisioned.

In this document we are going to deal only with the basic DICOM features. Namely:

the DICOM file format, and related issues like the concept of DICOM DIR
DICOM store, query and retrieve and further basic DICOM concepts, like the modality wor klist, the MWL. That is, the DICOM as the network communication protocol will not be discussed at all.

The DICOM standard was established by NEMA during the end of the nineteen-eighties of he 20th century, that is, more than 20 years ago. The need to create such a standard arose from the increasing number of digital imaging technics and devices. It became clear that without a well defined such standard the imaging centers owning different modalities would fall into chaos.

 
Nézzük meg az 1-es ábrát:

 
The programmers who developed the program creating the image above did not know the exact specification of the digital modality producing the images shown. Perhaps the imaging device in question had not even been envisioned yet by anybody when our programmers did their part of the work. And yet, the software could interpret these images, their size and orientation; and apparently some of the data attached. Without the DICOM standard this would have been unthinkable! We can already tell that DICOM is one of he most successful standard that has ever been nailed down by humans.

The DICOM standard is a system of written documents of thousands of pages, that is the deep understanding of the standard as a whole is impossible. This is why we had to restrict ourselves to what we wish to communicate to our readers. As I already said, only the very basics of the basics will be even approached.

 

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