Question 1

Which of the following are parameters of image quality? 
I. spatial resolution
II. contrast resolution
III. noise

Accepted Answer

Essentially there are three main parameters of image quality: spatial resolution, contrast resolution, and noise.

Question 2

Which of the following are physical properties of detectors? 
I. high luminescence efficiency
II. large dynamic range
III. small afterglow

Accepted Answer

Detectors for multislice computed tomography scanners should have several properties, which include a large dynamic range, high quantum absorption efficiency, high luminescence efficiency, good geometric efficiency, small afterglow, and high precision machineability.

Question 3

In a multislice computed tomography scanner, what type of algorithm can be used if the number of detector rows is small?

Accepted Answer

Fan-beam reconstruction can be used if the number of detector rows is small.

Question 4

Which of the following are considered cone-beam algorithms? 
I. approximate algorithms
II. exact algorithms
III. opposed algorithms

Accepted Answer

Cone-beam algorithms fall into two classes: exact algorithms and approximate algorithms.

Question 5

In 1992, the first modern multislice scanner was introduced by:

Accepted Answer

In 1992, Elscint introduced the first modern multislice scanner, which used dual detector banks.

Question 6

What type of detector is used in multislice computed tomography scanners?

Accepted Answer

The most significant difference between single-slice and multislice computed tomography is the detector technology: multislice computed tomography uses solid-state scintillation detectors.

Question 7

The first model of the 256-slice four-dimensional computed tomography scanner was developed in:

Accepted Answer

The first model of the 256-slice four-dimensional computed tomography scanner was developed at the National Institute of Radiological Sciences in Japan in 2003.

Question 8

All of the following are materials used in solid-state detectors except:

Accepted Answer

The detector elements of multislice computed tomography scanners use solid-state materials (scintillation crystals or ceramics) such as cadmium tungstate and, more recently, rare earth materials such as gadolinium oxysulfide, or yttrium-gadolinium oxide, gadolinium oxide, or ceramics.

Question 9

All of the following are housed in the multislice computed tomography gantry except:

Accepted Answer

The multislice computed tomography gantry houses the x-ray generator, the x-ray tube, and detectors, as well as the detector electronics. It does not house the collimation selector.

Question 10

Dual-source computed tomography scanners are primarily used for:

Accepted Answer

In 2006, a computed tomography scanner primarily for cardiac imaging (and other applications as well) was introduced at the Radiological Society of North America meeting.

Question 11

When the slice thickness is equal to the pixel size, the data acquired are said to be:

Accepted Answer

When the slice thickness is equal to the pixel size, all dimensions of the voxel (x, y, z) are equal. In other words, the voxel is a perfect cube, and the data set acquired is said to be isotropic.

Question 12

Which of the following is a popular tilted plane reconstruction?

Accepted Answer

One popular tilted plane reconstruction algorithm is the advanced single-slice rebinning algorithm used by General Electric Healthcare and by Siemens Medical Solutions.

Question 13

Which of the following are considered categories of approximate cone-beam algorithms? 
I. two-dimensional algorithms
II. three-dimensional algorithms
III. four-dimensional algorithms

Accepted Answer

Approximate cone-beam algorithms fall into two categories: three-dimensional algorithms and two-dimensional algorithms.

Question 14

The computer systems of multislice computed tomography scanners have hardware that provides all of the following except:

Accepted Answer

These computers have hardware architectures that provide high-speed preprocessing, image reconstruction, and postprocessing operations.

Question 15

What term is used to describe the number of data collection channels and the effective section thickness determined by the data acquisition system settings?

Accepted Answer

The term detector configuration is a term that describes the number of data collection channels and the effective section thickness determined by the data acquisition system settings.

Question 16

Which of the following is/are types of detectors used in multislice computed tomography scanners? 
I. hybrid detectors
II. nonuniform detectors
III. uniform detectors

Accepted Answer

All of the above are types of detectors used in multislice computed tomography scanners.

Question 17

All of the following are advantages of multislice computed tomography except:

Accepted Answer

Decreased contrast resolution is not an advantage of multislice computed tomography scanners.

Question 18

The operator console controls all of the following except:

Accepted Answer

The operator console controls the entire computed tomography scanner system and facilitates the selection of scan parameters and scan control (automatic or manual), image storage, communication, image reconstruction, image processing, windowing, and control of the gantry and x-ray tube rotation.

Question 19

Which of the following are algorithms that were developed to reconstruct from variable slice thicknesses? 
I. longitudinal interpolation by z-filtering
II. spiral/helical scanning by interlaced scanning
III. spiral/helical scanning by optimized sampling

Accepted Answer

Two algorithms developed to reconstruct from variable slice thickness include longitudinal interpolation by z-filtering and spiral /helical scanning by interlaced scanning.

Question 20

What term is used to describe the resorting of the three-dimensional data collected from the cone-beam acquisition to a set of two-dimensional fan-beam data?

Accepted Answer

The principle is based on the notion of rebinning, a term used to describe the resorting of the three-dimensional data collected from the cone-beam acquisition (geometry) to a set of two-dimensional fan-beam projection data and subsequent use of the conventional two-dimensional fan-beam projection algorithm to reconstruct transaxial images.

Quiz 12: Multislice Spiralhelical Computed Tomography: Physical Principles and Instrumentation

Which of the following are parameters of image quality? I. spatial resolution II. contrast resolution III. noise

Which of the following are physical properties of detectors? I. high luminescence efficiency II. large dynamic range III. small afterglow