Exam 9: Image Quality

On an image, partial volume artifacts will appear as: I. bands II. shading III. streaks

Partial volume artifacts can be reduced with _____________ slice acquisitions and computer algorithms.

Artifacts can: I. degrade image quality II. affect the perceptibility of detail III. lead to misdiagnosis

What is the most straightforward way to reduce or eliminate the motion of an object?

Although factors affecting resolution are largely determined by computed tomography manufacturers, operators do have a great deal of control.

A small focal spot size or lower tube current will result in:

Which of the following is defined as the smallest object that can be visualized at a given contrast level and dose? I. high-contrast detectability II. low-contrast detectability III. low-contrast performance

As a result of volumetric computed tomography, the scatter-to-primary ratio decreases.

The averaging of all tissues in a voxel is:

The fact that noise in the reconstructed images is no longer white describes: I. noise power spectrum II. Wiener spectrum III. reconstruction spectrum

Which of the following refers to the relationship of computed tomography numbers to the linear attenuation coefficients of the object to be imaged?

Which of the following can be used to compare the performance of different computed tomography systems?

Cross-plane spatial resolution is traditionally described by the:

If the field of view is 30 cm with a matrix size of 512 * 512, what is the pixel size?

Which of the following describes an object whose thickness is significantly smaller than the slice thickness of the system?

One of the disadvantages of computed tomography over conventional radiography is its ability to observe low-contrast objects whose density is slightly different from the background.

Pixel size is determined by:

To sharpen the image, a convolution process (a ramp filter) is applied to modify the frequency contents of the projection before back-projection.

All of the following are major categories of artifacts except:

Which of the following is not a source of image noise?