Overview of PACS

1. Picture Archiving and communication in
Medicines ( PACS)
Anjan Dangal
B.sc. Medical Imaging Technology
National Academy of Medical Sciences, Nepal

2. Introduction
• PACS, or Picture Archiving and Communication in Medicine is a
medical Imaging Technology used for storing, retrieving, presenting
and sharing images produced by various medical imaging modalities
such a x ray, CT scan , MRI and Ultrasound.
• In recent years, however, PACS technologies have also started to
incorporate images produced by other departments, such as
cardiology, pathology, oncology and dermatology.

3. Main Advantage
• Helps in image transmission from the site of image acquisition to
multiple physically-disparate locations.
• This technology not only is economical (film-less department), but
also convenient to access multiple modalities (radiographs, CT, MR,
ultrasound etc.) simultaneously at multiple locations within hospitals
or across the globe.
Ref: https://radiopaedia.org/articles/picture-archiving-and-communication-system
https://searchhealthit.techtarget.com/definition/picture-archiving-and-communication-system-PACS

4. Best Part of PACS
• Once an image has been acquired onto PACS it cannot be lost, stolen,
or misfiled. (images are always available after a PACS has been
installed, so no patient appointment is cancelled, no clinical decision
deferred, no images are repeated because they are missing, and no
time is wasted by doctors or other healthcare workers looking for
missing films.)
• The PACS database ensures that all images are automatically grouped
into the correct examination, are chronologically ordered, correctly
orientated and labelled,and can be easily retrieved using a variety of
criteria (forexample, name, hospital number, date, referring clinician,
etc).

5. • Alteration of the contrast width and level allows soft tissue and bony
structures to be well seen on a single exposure.
• PACS does allow some direct economic savings from the lack of
expenditure on film, film packets, film processing chemicals, staff
salary savings from darkroom technicians,

6. PACS Architecture
• PACS has major component and are:
• input from digital or digitaIised analog devices, which may be any
radiological modality e.g. X-ray, CT, MRI or ultrasound
• image acquisition device
• image storage device/server for short or long term storage of data
• transmission network: local or web-based
• display stations: imaging workstation and user interface
• camera: to convert into hard-copy images on need basis
• integration with radiology information system (RIS) and hospital
information system (HIS)
Ref: https://radiopaedia.org/articles/picture-archiving-and-communication-system

7. Disadvantages of PACS
• PACS is expensive.
• A PACS failure, unlike the failure of any other imaging equipment, has
such devastating consequences for clinical care that even a minimum
delay in resolving the problem is unacceptable.
• Another potential problem of a PACS is the fear that medical staffwill
not have sufficien computer literacy to be able to use the new
technology.
• The major limitation of PACS or teleradiology devices, is the quality of
images, which may be compromised by suboptimal resolution display
monitors at different locations.

8. PACS and RIS
• A radiology PACS is frequently deployed alongside an RIS.
• An RIS is used to schedule patient appointments and record a
patient's radiology history, while a PACS focuses more on image
storage and retrieval.
• Many RIS platforms have been replaced or are being replaced by
PACS technologies and VNAs.

9. CLOUD PACS
• A cloud-based PACS is a type of PACS architecture that's used to store
and back up a healthcare organization's medical imaging data to an
off-site server that is not within the organization's physical or on-
premises location.
• A cloud PACS can also enable medical staff to view medical imaging
data from any of their approved devices.

10. Vendor Neutral Archieves
• A vendor neutral archive (VNA) is a technology that stores medical
images in a standard format and interface, making them accessible to
healthcare professionals regardless of what proprietary system
created the images.
• VNAs enable healthcare organizations to consolidate, standardize,
and archive images and data from different picture archiving and
communication systems (PACS) into a single, easily accessible and
interoperable repository.
• The trademark of VNAs is exchanging image information from various
PACS regardless of the vendor; by comparison, PACS do not exchange
data with each other well.

11. Need of VNA
• Medical images are often stored in DICOM formats
• As medical imaging technology use has spread to other departments,
such as neurosurgery, DICOM now includes extensions for other care
areas.
• Different PACS vendors use different syntaxes within DICOM, which
makes it difficult for data from one system to work in another
vendor's setup. VNA technology deconstructs data from the
originating PACS and then migrates the data to the new system under
the proper syntax, enabling data integration, according to a 2012
piece in the Indian Journal of Radiology and Imaging.