Physics and Radiobiology of Nuclear Medicine

patient on his/her computer from other locations within the PACS, rather

than waiting for the hardcopy from the imaging department. He/She can

then correlate the images with the clinical findings with a considerable

saving of time. A typical integrated PACS is shown in Figure 11.4.

A PACS can be run by software on different operating systems such as

Windows, MAC OS, Linux, or UNIX, although most PACS workstations

are PC-based. PACS software must preserve confidentiality of patient

information as mandated by the U.S. Hospital Insurance Portability and

Accountability Act (HIPAA). The system must be reliable so that its down-

time is nil. Also, the integrity of the system should be intact to avoid any

medical errors in the patients’ information. It should be always and easily

accessible to all concerned to avoid delay in patient care. PACS software is

constantly evolving to meet the new demands of healthcare professionals,

and it is usually upgraded every 6 to 12 months. Numerous vendors (CTI/

Siemens Medical, GE Medical, Phillips Medical, Kodak, Stentor, Spectra,

etc.) have made commercially available their copyrighted PACS software,

which are claimed to be robust, reliable, and user-friendly, with an uptime

of more than 99.9%. A drawback is that there is a lack of a uniform stan-

dard among PACS software. It is desirable that the medical community, and

perhaps the federal government, come up with a consensus policy similar

to DICOM to make PACS uniform among different vendors.

An important application of PACS is in teleradiology which is being

implemented throughout the country, and even worldwide between coun-

Application of Computers in Nuclear Medicine 151

X-rays

MRI

RIS

CT

PET

SPECT

Network

Hub

Teleradiography sites

Hospital Admin

Physicians

Referring

Lab Med

Archive Server

HIS

Fig. 11.4. A PACS integrating the networks of HIS and RIS.