munications in Medicine (DICOM), which all vendors are recommended
to adopt for compatibility among different software. Some of the standards
of DICOM formats include image storage, protocols for intertransfer of
data between the workstation and PACS (see later), query and retrieval of
image data, print, and scheduling of data acquisition. DICOM formats are
encoded in binary form. NEMA upgrades DICOM formats from time to
time to meet the requirements of advancing technology and the medical
community.
Essentially, vendors conform to the DICOM standard in developing their
software, although compliance is voluntary. It provides a common format
for imaging systems recognized by the hardware and software components
of various manufacturers. This allows interoperability in the transfer of
images and associated information among multiple vendors’ devices.
DICOM is very useful in the implementation of PACS (see below).
PACS
The modern networking of computers has offered a great advantage for
exchange of information among individuals and organizations. It has been
particularly useful for healthcare facilities in exchanging patient informa-
tion among the physicians and hospitals. One type of network systems
implemented in healthcare facilities is called the Picture Archiving and
Communication System (PACS) and is solely used for the archiving and
exchanging of patient information among health professionals. A PACS
consists of devices to produce and store digital images electronically, work-
stations to view and interpret images, and a networking of these devices at
different sites. Appropriate PACS software allows the interpreter to retrieve
images from other locations and manipulate and interpret them as needed
at his own location, and then return them with a report back to the origi-
nal locations. In the absence of PACS, one can read the images only at the
local facility and cannot transport them electronically to and from other
facilities, if needed. PACS has improved the workflow profoundly by facil-
itating and expediting the transfer of information through network con-
nections among various facilities.
In a radiology department, a small network system called the Radiology
Information System (RIS) is normally implemented to maintain all types
of workflow, such as image storage, patient scheduling, study type and its
time of completion, image reporting, all the billing codes, and so on, within
the department. Similarly, hospitals also have the Hospital Information
System (HIS) that maintains similar information on patients including their
demographic data, laboratory data, clinical history, and medication, and
again, scheduling, tracking, reporting, and billing. A PACS can integrate
both RIS and HIS for a broader exchange of information among health-
care personnel that will save time and money in healthcare operations. In
such an integrated system, a referring physician can retrieve an image of a
150 11. Digital Computers in Nuclear Medicine