Image Production II

Who introduced the CT scanner?

Gadolinium oxysulphide is considered to be a(n):

When signal is reproduced, frequencies above the Nyquist frequency will cause:

Early PACS systems moved images from __________ to established hospitals.

Referred to as the image's appearance on the display monitor of the computer.

With PSP and FPD, radiographic contrast is controlled by what?

Window level represents

In PSP systems, a _____________ scanned over the plate releases the latent image.

This layer of the cassette sends the light in a forward direction.

Most storage phosphor plates are made of what?

Network in which the devices are connected in a circle.

Similar to a hub but sends data only to those devices in which the data are directed.

Number of bits within a pixel is known as?

Cassettes are backed by a thin sheet of aluminum that absorbs what?

Constant measure to be monitored is to make sure all images make it to ______.

On a histogram, values on the left represent ______ areas.

Relationship between the height of the lead strips and the space between the lead strips

Noise created by the lack of light photons from the scintillator

In conventional x-ray, exposure latitude is based on....

Systems that are a simply light proof container that protects image plate from light & handling

Slow scan (image plate through the reader) is also known as

Each pixel or ____ contains 3 electrodes that hold the electrons in an electric potential well.

Image acquisition, display workstations, & archive servers are 3 fundamental parts of:

The internet is based on what kind of network topology?

In conventional x-ray, optical density is primarily controlled by what?

Amount of detail present in any image is known as it's:

Two or more objects sharing resources/info; devices interconnected by communication channels

Image management station is also known as:

T or F: 3 types of compression are lossless, lossy, and no compression

Which is not a following type of noise associated with CCD technology

How long does it take between exposures for the plate to erase the old image?

Cracks in the plate appearing as radioluscency on the image are known as

T or F: In client/based systems, if the archive goes down, the entire system is still operable.

How efficiently a system converts x-ray input signal into a useful image.

Traditionally kVp was chosen for _________.

T or F: The first Thin Film Transistors were made of amorphous silicon and amorphous selenium

Modulation transfer function (MTF) is the ability of the system to record available __________.

What are the two types of PSP readers?

ADC stands for...

Any computer that a health care worker uses to view a digital image

Gadolinium oxysulphide material is made from small crystals in an unstructured or ______ layer

Reading of pixel values could be off because of all of the following, except:

True or False: Quality can be considered a service or a product.

Window width represents

Movement of the image plate through the reader.

Anything that interferes with the formation of the image.

Line scan readers use a ________ linear array photodetector.

T or F: RIS holds patient's full medical info, HIS holds all radiology specific data

In digital x-ray, density is controlled by what?

DICOM is standards that allows PACS and __________ to communicate in the same language.

Ability of imaging system to demonstrate small details of an object.

Imagers that use heat to process latent image that is etched into the silver emulsion by laser

May be used to look up exams for a physician or print copies of images for the patient

High resolution image plates contain a _______ phosphor layer compared to the standard plates.

In client/based servers, archive server is handling many requests at once and can become:

Allows tech to match image information with patient information.

How many people at one time can open a study on client/server based systems?

Short term memory storage for open programs

Moving images via telephone lines to & from remote locations is referred to as...

Thinner plates result in ______ image sharpness bc of reduced amount of light spreading.

The two ways to measure detector performance (select two):

Typical grid frequency is between ____ and _____ lines per inch

T or F: two types of scinitillation layers are structured and unstructured

In direct capture, energy is detected by a ________ that converts it into an electric signal.

RAM takes data from the _______ so it can handle processing needs of running programs

Surpressing frequencies, also known as ________ can result in loss of small details.

Adding a black background around the original collimation edges, this is known as:

Comprehensive set of activities designed to monitor & maintain systems that produce a product

A place where records or documents are preserved

Movement of the laser across the imaging plate.

T or F: the two types of film digitizers are laser digitizers and CCD digitizers

Initial digital image appears linear when graphed bc all gray shades are visible, resulting in:

T or F: matrix size change will affect FOV, but FOV or matrix change won't affects pixel size.

Changes to images before PACS reduces the amount of manipulation the ________ can do.

In indirect capture, this gives off light that is detected and turned into an electric signal.

Smallest element in a digital image, also known as picture element.

Should be monitored from modality to PACS & from archive to workstation

In digital x-ray, mAs has more influence on _______ than on density.

Early CT machines took a few ________ to reconstruct raw data into a recognizable image.

CCD is only included in what process(es)?

When do you erase cassettes if you are unsure of the last erasure?

Early PACs systems were developed by...

RAID stands for:

Imagers that use chemicals to process film that has been exposed to the laser

Range of exposure diagnostic image values the image detector is able to produce.

In digital x-ray, images will appear on the monitor in what amount of time?

T or F: image is digitized by both position (spatial location) and intensity (gray level)

Converting digital input data to an image w/appropriate brightness & contrast is referred to as

Universally accepted standard for exchanging medical images

White lines parallel to the direction of plate travel caused by dust or scratches are known as

The ability of a digital system to display subtle changes in the shade of gray.

Many PACS reading stations also have what capability?

Used to review images after acquisitions but before sending them to the radiologist.

In direct conversion, more than __________ pixels can be read & converted to image in 1 second

On most digital systems, kVp values range from:

True or False? PACS provides image access to multiple users at the same time.

Reject analysis is performed how often

Indirect capture is similar to PSP because x-ray energy stimulates a.....

Process where x-ray energy is converted directly into an electrical signal.

Stationary grid can interfere with image and produce lines, known as the:

Grid lines will be finer/less interfering when the grid frequency is:

The first commercial CT scanners imaged only the...

Function that allows the QC tech to select one or more local computers to recieve images.

Noise occurs when the CCD chip operates w/o radiation stimulation

Who will need to clean or replace the light guide on a damaged plate reader?

Direct capture uses __________ as an x-ray absorber.

The ________, or microprocessor, is a small chip found on the mother board.

Considered to be the second major milestone in medical imaging

Common measurements functions include all of the following except:

PACS can accept any image that is in ________ format.

In general projection radiography PSP imaging, resolution is approximately:

Maps the image grayscale values into visible output intensity on a monitor or printed film.

Network with multiple pathways interconnecting devices and networks

Plan for the systematic observation & assessment of diff. aspects to make sure standards met

Aliasing (also called foldover/biasing) causes mirroring of the signal at _____ the frequency.

A device/system that captures or measures a continuously changing signal.

Used to blacken out the white collimation borders, effectively eliminating veil glare.

Network which all devices are physically attached to & listen for communication on single wire

Important phase in establishing parameters that determine collimation & histogram function

CMOS was developed by what company?

Digital images are recorded as multiple _________ and divided into array of small elements.

T or F: biggest advantage of CCD relates to demagnification issues and reduced DQE

Type of radiography that uses film & intensifying screens in it's image formation process

A networked group of computers, servers, and archives used to manage digital images.

Amount of exposure received by the image receptor.

Uncommonly, malfunctions in the detector can cause:

Who can fix broken latches or hinges?

Which phosphor produces more lightspread/decreases efficiency when stimulated?

True or false: changes in the matrix size will not affect pixel size.

True or False: PSP systems are less sensitive to low levels of radiation.

Used to move through images, series, studies, and patients

More pixels = _______ image resolution

A perfect system would have an MTF of ______?

In indirect conversion, the phosphor layer is also known as the ________ layer

These systems use an x-ray absorber material coupled to a TFT or CCD to form images.

Following are all techniques to reduce possibility of image lag, except:

Data within a collimated area produces a graphic representation of optical densities called a?

Storage phosphor plates are similar to...

X-ray photons are absorbed by coating material & immediately converted into electrical signal

Series of connections, controllers, & chips that creates information highway of the computer

Amount of electrons produced relative to the incident light from the scintillator

In conventional radiography, contrast is primarily controlled by what?

MRI was introduced in what decade?

TJC (formerly JCAHO) accreditiation necessary for all the following except:

Acquisition modalities send images to designated reading stations in what type of system?

System in which images are sent directly to archive server after acquisition

Which of the following is not a major OS in use today?

In indirect conversion, signals are first converted to _______ and then to an electrical signal

Refers to the number of grid lines per centimeter or lines per inch

QC technologists perform testing how often

Moire effect happens because the grid lines and the scanning laser are:

An appropriate grid for portables is 6:1, where as an appropriate grid for the department is:

PSP plates record a _______ range of exposures, so only the optimal density range is processed.

True or False: In client/server based systems, any exam sent to PACS is available anywhere

Network that spans large area, used to connect computers that aren't physically attached

Small area networked w/series of cables or wireless access points; devices on same network

Post processing is performed by who?

If image is taken prior to detector releasing signal from previous image, what can happen?

Indirect conversion uses a phosphor such as ___________ to absorb x-rays and produce light

Most popular type of amorphous silicon detecter uses a ______ scintillator.

Process where x-rays are absorbed, converted to light which is converted to an electric signal

Network w/centralized computer that controls operations, files, and sometimes programs

Film is inside a cassette that contains an intensifying screen in ________ radiography?

More light spread will result in ________ MTF.

Software that controls computer hardware & acts as a bridge btwn applications & hardware

T or F: a field effect transistor or silocon TFT reacts like a switch (in direct conversion)

Cassettes contain ______ to protect against static electricity, dust and mechanical damage.

On the LUT, contrast can be increased or decreased by changing what?

On the LUT, _________ is increased and decreased by moving the line up or down the y-axis.

The ability to respond to varying levels of exposure that allows seeing more tissue densities

PSP reader that has optical stage, scanning laser beam, photomuliplier, & ADC converter.

A cassette's phosphor layer is also known as it's

Number of gray tones a pixel can produce is _____ to the power of the bit depth.

Edge enhancement is also known as

Simplest device that can be used to connect several pieces of equipment together

Any undesirable densities on the processed image other than those caused by scatter or fog

Type of motion that will blur the grid lines and eliminate interferance

Scans the analog film and produces numeric signals for each part of the scanned film

This digital acquisition modality uses storage phosphor plates to produce projection images.

Will changes in the field of view affect the size of the pixel matrix?

When insufficient light is produced, image is grainy, a condition known as

Occurs when fewer pixels in the nieghborhood are included in the signal average.

Each pixel contains pieces of information called _______.

A line of TFT switches allows electrical charge info to discharge when switches are _______.

When images are produced with uniform density and contrast, regardless of exposure amount.

This layer traps electrons during exposure, commonly made of barium fluorohalide.

Cheapest form of storage:

Noise that occurs when some pixels in the chip don't work at all, common in digital

Indirect conversion detectors are similar to direct because they use _________

In direct conv., each pixel contains a ____ that absorbs electrons & generates electric charges

One of the first uses of digital imaging was in...

Functions primarily used radiologist to increase size of an image area are all of these except:

In PSP, the light is picked up by one of these two things then converted to an electric signal?

True or false: facilities prefer when the tech manipulates images before sending them to PACS

Plate is scanned, image location & then signal size determined, & value is placed on each pixel

Organization that sets standards that are used in most health care applications, btwn HIS & RIS

Type of OS used to control specific machinery, such as digital x-ray consoles

Which is most inexpensive, easier to repair, and more simple? TFT or CCD

If an image has a bit depth of 8, how many shades of gray are in the image?

DICOM stands for Digital Imaging Communication ____________________

Ultimate focus in health care is:

True or False: Digital images are formed through multiple samplings of a signal.

T or F: background signal is unimportant therefore imaging plates don't need to be erased

T or F: info can never be misrepresented or lost even if there's defects in operation of device

Reduction of the area of the beam that reaches the patient through the use of lead shutters

CT units took several ________ to acquire a single slice of information