Chapter 9: PACS Fundamentals

Picture Archiving and Communication System (PACS)

What is a network of computers, servers, and storage devices for the distribution and display of medical images?

Medical Image Management and Processing System (MIMPS)

What is PACS also called?

- Imaging Acquisition

- Display Workstations

- Archive Servers (storage)

What are the fundamental components of PACS?

The radiologist's reading room and file room

What is PACS the electronic version of?

Archiving

What is the part of PACS that houses all historic image data and current image data?

Digital Imaging and Communications in Medicine (DICOM)

What is the universally accepted standard for exchanging medical images among modalities, viewing stations, and the archives, along with laying the groundwork for the future development of integrated PACS?

DICOM

Every modality and PACS communicates via _________

Mini-PACS networks

In early ultrasound, what became a norm in many hospitals?

The transition to soft-copy reading

In CT and MRI, as the image sets increased, what became necessary?

Display Workstation (Clinical Workstations)

What is any computer a healthcare worker uses to view a digital image?

Inside and outside of the radiology department

Where are display workstations used?

Display workstations

What is the most interactive part of PACS?

The display station

On the display workstation, what receives images from the archive or various radiology modalities and presents them for viewing?

PACS application software

What does the display workstation have that allows for minor image manipulation?

Archive Servers

What is the central part of the PACS that houses all of the historic and current image data, which may also serve as the central hub that receives all images before they are released for interpretation?

file room

Archive servers are considered the _______ ________ of the PACS

- Database server or image manager

- Short and long term storage

- Workflow manager

What three things do archive servers consist of?

A monitor and a computer with a mouse and keyboard

What does the display workstation or clinical workstation consist of?

Large multiviewer lightboxes

In conventional film-screen radiography, what was used as the display workstation?

Four to six monitors

With early PACS, how many monitors did radiologists think they would need?

An average of two

As radiologists have become more comfortable with PACS, how many monitors do they use?

Monitors: Liquid Crystal Display (LCD) and Cathode Ray Tube (CRT)

What are the most important elements of the display workstation? What are the two types?

Cathode Ray Tube (CRT)

What type of monitor is heavy, puts off a lot of heat, is very bright, can be viewed from any angle, and is an older piece of technology?

Liquid Crystal Display (LCD)

What type of monitor is smaller in size, has less heat production, requires less maintenance, gives more light, and can be used in areas with a high amount of ambient light?

Resolution and Orientation

What are the two factors that are used in determining which type of monitor is to be used?

A 1k square monitor

What type of monitor is cross-sectional imaging (CT, MRI, Ultrasound) read on?

A 2k portrait monitor

What type of monitor is most digital projection images read on?

Resolution

What is the number of pixels contained on a display monitor?

Resolution increases and more information can be displayed

The more pixels there are on a monitor, what happens to the resolution?

Resolution

What is defined as the process or capability of distinguishing among individual parts of an image that are adjacent?

1k, 2k, 3k, and 5k

What are the common screen resolutions found on today's monitors?

The radiologist display workstation

What display workstation has the highest resolution monitors available?

5k or 5-megapixels

What kind of monitor resolution does mammography require?

A 1k monitor

Because the referring physician is not the primary doctor reading the exams, what kind of monitor would be sufficient for his or her viewing needs?

Radiologist Reading Station

What display workstation is used by the radiologist to make a primary diagnosis and has the highest quality hardware, including the best monitor?

1 week of data

What must radiologists' reading stations be able to store?

RIS / dictation

At the radiologist reading station access to the _____ is nearby and a _________ system is near

The RIS and dictation systems

What are the many systems integrating within the PACS software for the radiologist reading stations?

Physician Review Stations

What type of display workstation is a step-down model of the radiologists' reading station that may have the same level of software but with reduced advanced functions?

The ability to view current and previous reports with images

What is one of the most important features of the physician review station?

The ability to view the same set of images in multiple locations at once

What is one of the greatest advantages of PACS?

Technologist QC Station

What type of display workstation is used to review images after acquisition but before sending them to the radiologist?

Image quality characteristics

What can technologist QC workstations be used to improve or adjust?

Patient demographic information

What can technologist QC workstations be used to verify?

To ensure that images meet the departmental quality standard

Why are technologist QC workstations placed between the CR and DR acquisition modalities as a pass-through?

A 1k monitor

What type of monitor does the technologist's QC station generally have?

The appearance too much of the original acquired image

On the technologist QC stations, when manipulating images, what should the technologist be careful not to change the appearance of?

query / retrieve; To check previous pathology or body characteristics

Tehcnologist QC stations can be used to _________ and _________ historic images. Why is this done?

The selection of technical factors or procedural protocols

What can technologist QC stations help with?

The file room

Before PACS, what was a large open room with endless rows of shelves full of film jackets?

The file room workstation

What type of workstation may be used to look up exams for a physician or to print copies of images for the patient to take to an outside physician?

Burning compact disks (CDs) or DVDs

Because of the cost of printing films, what are hospitals moving towards to give patients their images?

- CDs are less expensive

- CDs can be made quickly

- CDs come with easy-to-use software burned into them

What are the three reasons why hospitals are burning CDs instead of printing film to give patients their images?

- Navigation

- manipulation / enhancement

- management

- advanced

Common PACS Workstation Functions:

- _____________ functions

- Image _____________ and ______________ functions

- Image ______________ functions

- ______________ workstation functions

Advanced functions

Most of the functions on a PACS workstation are available on any level workstation, except for which function is specific to different types of workstations?

Navigation function

What type of PACS workstation function is used to move through images, series, studies, and patients?

The windows look and feel

What does modern PACS software conform to?

A mouse

What is a useful navigation tool that, when clicked on the right side of the tool, offers many shortcut features in a menu of frequently used tasks and applications?

Hanging protocols

What defines how a set of images will be displayed?

On four images that can be viewed on each monitor

Since users can customize the hanging protocol for each modality, how are CT exams selected?

Can be viewed as one image on each monitor

Since users can customize the hanging protocol for each modality, how are CR images selected?

The previous exam on one monitor and the current exam on the other

What can the hanging protocol be set to show on one monitor and on another monitor at the same time?

Study

In PACS, what refers to the current or previous exam being viewed?

Two or three single images

In a study, like projection radiography, how many images may it consist of?

A series of several images

In a study, like MRI, how many images may it consist of?

scroll / arrows

In study navigation, images can simply be paged through with the ________ wheel or________ on the keyboard

Cine

What is the mode of scrolling through the images made called, which means to move through frame by frame in a series of images?

In cross-sectional imaging

Where is the Cine function most often used?

Provides icons

What do many vendors provide that allows the user to move between a patient's various studies, open the next unread patient file in the worklist, and close the patient/close the study?

- window width and window level

- annotations

- flip and rotate

- pan, zoom, and magnify

- measurements

On image manipulation and enhancement functions, what are the commonly used tools that are available to change the appearance of the image?

Modality Worklist (MWL)

What is a component of DICOM that makes patient demographics from the RIS available at the modality and prevents data-entry errors?

Window Width

What represents the range of gray values?

Window level

What represents the center value of the range?

Appears to change the brightness and contrast

A change in the window and level changes what in the image?

Annotate text or graphics

What can most PACS systems add to the image?

False

Annotations should be used to label left or right to indicate the patient's side. True or False

Flip and Rotate

What tool is used to orient the image in the correct anatomic hanging position?

The use of R and L lead markers

What is important to use to ensure that the radiologist is reading the correct side of an image?

Digital right and left markers

What might not be considered admissible in court due to the capability to mark anywhere on the image and to flip or rotate it into any layout on the screen?

Pan, zoom, and magnify

What tools are used primarily by the radiologist to increase the size of an area on an image?

Magnify

What usually enlarges a square area of the image, and the square can be moved around the image to quickly see various areas?

Zoomed / Pan

- Image is first ________ up to the desired magnification level

- ______ icon is activated so that the bigger image can be moved around to view the different areas of the image

Distance and Angle measurement

What are the most common measurement functions found on a PACS workstation?

Distance Measurement

Because the pixel size is known, which software can be used to measure structures within the image based on that known value?

Angle measurement

What measures the angle between two structures and is commonly used when reading spine studies?

Region of interest (ROI) Measurement

What is another common measurement tool that determines the pixel intensity of a certain area?

Determines whether something is solid or fluid

What does the ROI measurement help the radiologist determine on images?

At the technologist workstation, reading station, and file room station

Where can patient demographics be modified?

Images may be lost

If patient demographics are not correct at the archive level, what can happen to the images?

Query/Retrieve Icon

What is used to retrieve on demand any studies from the archive and allows users to request a study across multiple fields?

Advanced Workstation functions

What workstation function is usually placed on a specialty workstation for the radiologist and some on the technologist's QC station to further enhance images?

- Multiplanar reconstruction (MPR)

- Digital subtraction

- Stitching

What are the three most common advanced functions?

Multiplanar Reconstruction (MPR)

Which advanced workstation function is one of the most commonly used three-dimensional rendering techniques?

Digital Subtraction

Which advanced workstation function uses a computer to subtract information (bone, bowel) from an image to remove superimposed anatomy, leaving the desired structures?

A mask

What is the pre-contrast image that is acquired, and after the contrast is administered, the image is subtracted?

Stitching

Which advanced workstation function is used to combine multiple images into a single image, most commonly for full-spine radiographs and scoliosis series?

Grayscale Standard Display Function (GSDF)

What ensures that medical images are transferred to a DICOM-compatible display device with a consistent and uniform appearance?