1.
The moire effect is a grid error that occurs when using......
Correct Answer
A. Stationary grid
Explanation
The moire effect refers to a grid error that occurs when using a stationary grid. This effect happens when the grid pattern interferes with the scanning or imaging process, resulting in unwanted patterns or distortions in the final image. Using a moving grid or rotating anode can help minimize or eliminate this error, but a stationary grid is more likely to cause the moire effect.
2.
MAs is selected according to
Correct Answer
A. The number of pHotons needed
Explanation
The correct answer is "the number of photons needed." This is because mAs, or milliampere-seconds, is a measure of the quantity of x-rays produced during an exposure. The number of photons needed depends on the specific imaging study and the desired image quality. Increasing the mAs increases the number of photons, resulting in a higher image quality with improved visibility of anatomical details. Conversely, reducing the mAs decreases the number of photons, resulting in a lower image quality with increased noise. Therefore, selecting the appropriate mAs based on the number of photons needed is crucial for achieving the desired diagnostic image.
3.
What does TFT stand for?
Correct Answer
A. Thin film transistor
Explanation
TFT stands for thin film transistor. A thin film transistor is a type of transistor that is made using thin films of semiconductor material. It is commonly used in electronic displays such as LCD screens.
4.
The TFTs surface has a thin layer of what on it?
Correct Answer
A. AmorpHous selenium
Explanation
The correct answer is amorphous selenium. TFTs (Thin Film Transistors) have a thin layer of amorphous selenium on their surface. Amorphous selenium is a non-crystalline form of selenium that is commonly used in electronic devices like TFTs. It has properties that make it suitable for applications in photovoltaic cells and x-ray imaging. By using amorphous selenium in TFTs, it allows for efficient electron transport and enables the transistors to function effectively in displaying and controlling electronic signals.
5.
Which type of detector uses a scintillator?
Correct Answer
A. Indirect acquisition
Explanation
The type of detector that uses a scintillator is indirect acquisition. Scintillators are materials that emit light when they interact with radiation. In indirect acquisition, the scintillator is used to convert the radiation into light, and then the light is detected and converted into an electrical signal. This method is commonly used in medical imaging systems like X-ray detectors and gamma cameras. Direct acquisition, on the other hand, does not involve the use of a scintillator and directly converts the radiation into an electrical signal.
6.
Pixels are...
Correct Answer
A. Basic picture element
Explanation
Pixels are the basic picture elements that make up an image. They are small individual dots of color that combine together to form a complete picture. Each pixel represents a specific color and intensity, and when millions of pixels are arranged in a grid, they create a detailed image. Therefore, the correct answer is "basic picture element".
7.
A matrix is.....
Correct Answer
A. Square table of numbers
Explanation
The correct answer is "square table of numbers" because a matrix is a mathematical concept that represents a rectangular array of numbers, symbols, or expressions arranged in rows and columns. It is commonly used in various fields such as linear algebra, computer science, and statistics to represent and manipulate data. The term "square" indicates that the matrix has an equal number of rows and columns, resulting in a square shape.
8.
What is the term for the amount of recorded detail in digital images?
Correct Answer
A. Spatial resolution
Explanation
Spatial resolution refers to the level of detail that can be captured and displayed in a digital image. It represents the ability of a digital imaging system to distinguish and reproduce fine details. A higher spatial resolution means more detail can be captured and displayed, while a lower spatial resolution results in less detail. Therefore, spatial resolution is the term used to describe the amount of recorded detail in digital images.
9.
Which has higher spatial resolution?
Correct Answer
A. Film/screen
Explanation
Film/screen has higher spatial resolution compared to DR (Digital Radiography) and CR (Computed Radiography). Film/screen systems use traditional X-ray film that is exposed and processed to create an image, resulting in high detail and sharpness. On the other hand, DR and CR systems use digital detectors to capture X-ray images, which may have lower spatial resolution due to the pixel size and image processing algorithms. Therefore, film/screen is the preferred choice when high spatial resolution is required.
10.
What typically causes quantum mottle?
Correct Answer
A. Low mAs
Explanation
study guide page 6
11.
Window level adjusts what?
Correct Answer
A. Brightness
Explanation
Window level adjusts the brightness of an image. By adjusting the window level, the overall brightness of the image can be increased or decreased. This is useful in medical imaging, where different tissues may have different levels of brightness and adjusting the window level can help visualize specific structures or abnormalities more clearly.
12.
Window width adjusts what?
Correct Answer
A. Contrast
Explanation
Window width refers to the range of gray levels displayed on a medical image. By adjusting the window width, the contrast of the image can be modified. A wider window width will increase the range of gray levels displayed, resulting in higher contrast between different structures in the image. Conversely, a narrower window width will decrease the range of gray levels displayed, resulting in lower contrast. Therefore, window width adjustment directly affects the contrast of the image.
13.
Shuttering is...
Correct Answer
A. Electronic collimation
Explanation
Shuttering refers to the process of electronically aligning or adjusting the collimation of an image. It involves making precise adjustments to the alignment of the electronic components within a camera or imaging device to ensure that the image is properly focused and aligned. This process helps to reduce any errors or misalignments that may occur during the capturing of an image, resulting in a more accurate and clear picture.
14.
Which healthcare information system holds the radiology-specific information (scheduling and patient data)?
Correct Answer
A. RIS
Explanation
RIS stands for Radiology Information System, which is a healthcare information system specifically designed to hold radiology-specific information such as scheduling and patient data. This system helps in managing and organizing the workflow of radiology departments by providing access to patient records, appointment scheduling, and tracking of imaging studies. RIS plays a crucial role in the efficient functioning of radiology departments and ensures that all the necessary information related to radiology services is readily available for healthcare professionals.
15.
Fixing an xray film will...
Correct Answer
A. Remove silver halides
Explanation
Fixing an x-ray film involves the process of removing the unexposed silver halide crystals from the film. This is done by immersing the film in a fixing solution, which dissolves the unexposed silver halides and leaves behind only the developed image. Removing the silver halides is crucial as they can cause the film to darken over time if not properly fixed. Therefore, fixing ensures that the image on the x-ray film is stabilized and preserved for accurate diagnosis.
16.
Film X-rays are stored for how many years
Correct Answer
A. 5 - 7 years
Explanation
Film X-rays are stored for 5-7 years because during this time period, the images are still considered to be relevant and useful for medical purposes. After this period, the quality of the images may deteriorate, making them less reliable for diagnosis. Additionally, storing X-rays for longer periods of time would require more space and resources, which may not be practical or necessary.
17.
The first automatic processor was developed by what company?
Correct Answer
A. Kodak
Explanation
Kodak developed the first automatic processor.
18.
How many feet from your work station should your safelight be in the dark room?
Correct Answer
A. 4 feet
Explanation
The safelight should be placed 4 feet away from the work station in the dark room. This distance ensures that the safelight does not interfere with the light-sensitive materials being handled in the dark room. Placing the safelight too close can result in unwanted exposure and damage to the materials.
19.
PSP stands for .....
Correct Answer
A. pHotostimulable pHospHor plate
Explanation
PSP stands for Photostimulable phosphor plate. This is a type of imaging plate used in medical imaging, particularly in digital radiography. The plate contains a phosphor material that can store energy when exposed to x-rays. When the plate is scanned with a laser, the stored energy is released as light, which is then converted into a digital image. This technology allows for efficient and high-quality imaging in medical diagnostics.
20.
Soft-copy Display is
Correct Answer
A. Images on a monitor
Explanation
Soft-copy display refers to the visual representation of information or images on a monitor or screen, rather than on a physical medium like paper or film. This means that the correct answer, "images on a monitor," accurately describes the concept of soft-copy display. It implies that the information or images are displayed electronically and can be viewed, edited, or manipulated on a computer or other electronic device.