Deck 6: Iterative Reconstruction Basics

Question 1

As documented by a 2012 performance evaluation, what percentage of dose reduction did the ASIR algorithm result in when compared to the FBP algorithm for a CT chest exam?

A) 10.8%
B) 26.4%
C) 32.5%
D) 46.4%

Answer 1

46.4%

Question 2

What model is the Adaptive Iterative Dose Reduction (AIDR) 3D algorithm based?

A) Physics
B) Optics
C) Object
D) Scanner

Answer 2

Object

Question 3

The first IR was used by Professor Allan Cormack.

Answer 3

False

Question 4

By modeling noise properties and the scanned object first, the following limitations due to noise in the reconstructed image are overcome except:

A) lower dose exams.
B) large patients.
C) thin slices.
D) decreased pitch.

Question 5

Two key features used in FBP algorithms to produce an image is convolution filtering and back-projection.

Question 6

Limitations presented by the filtered back-projection (FBP) algorithm include each of the following except:

A) image noise.
B) artifact creation.
C) patient dose.
D) speed.

Question 7

In a 2015 performance evaluation, it was noted that the reduced dose Iterative Model Reconstruction (RD IMR) algorithm proved significantly better than reduced FBP (RD FBP) algorithm in each of these pathologically processes except:

A) intracranial hemorrhage.
B) hepatic cysts.
C) stones.
D) colonic diverticula.

Question 8

The IR loop is responsible for producing raw data and subjecting it to the standard FBP algorithm.

Question 9

What step in the typical IR process generates the initial CT image from an FBP algorithm?

A) Input
B) IR loop
C) Modeling
D) Output

Question 10

CT manufacturers offer each of these categories of IR algorithms commercially except:

A) iterative methods without modeling.
B) statistical methods with modeling of photon counting statistics.
C) FBP algorithm.
D) model-based methods, that exceed statistical modeling.

Question 11

The criteria used to evaluate IR's performance in various studies include each of the following except:

A) noise reduction.
B) data acquisition speed.
C) dose reduction.
D) image quality improvements.

Question 12

The term iterative refers to the characteristics of the CT imaging system and the imaged object.

Question 13

Which of the following is not a primary goal of iterative reconstruction (IR) algorithms?

A) Reduce image noise with lower exposure technique
B) Preserve spatial resolution at lower exposure techniques
C) Reduce photon starvation artifacts
D) Reduce artifacts caused by patient motion

Question 14

The primary goals of IR include all of the following except:

A) improve image quality.
B) reduce noise.
C) improved high-contrast detectability.
D) artifact reduction.

Question 15

What term describes the difference between the simulated raw data and measured projection raw data?

A) Model
B) Projection
C) Correction term
D) Algorithm

Question 16

What term is known as a calculation process using a series of operations that are repeated several times?

A) Projection
B) Iterations
C) Model
D) Domain

Question 17

FBP algorithms assume that all X-ray photon interactions take place across the full area of the detector array.

Question 18

What area of modeling does the Adaptive Statistical Iterative Reconstruction-V (ASIR-V) algorithm not focus?

A) Noise
B) Optics
C) Object
D) Physics

Question 19

The primary goal of IR algorithms is to reduce image noise when using lower exposure technique factors, and at the same time preserving image quality.

Question 20

Which model addresses the X-ray source, image voxel, and detectors?

A) Optics model
B) Noise model
C) Object model
D) Physics model

Question 21

Please match each of the following IR algorithms to the vendor who introduced it. Answer selections will be used only once.

SAFIRE

A)GE Healthcare Systems
B)Siemens Healthcare Systems
C)Philips
D)Toshiba Medical Systems

Question 22

The IR loop process is complete once a predefined quality criterion in the image estimate is fulfilled.

Question 23

The physics model considers the radiation attenuation interactions that occur within the patient.

Question 24

Please match each of the following IR algorithms to the vendor who introduced it. Answer selections will be used only once.

AIDR 3D

A)GE Healthcare Systems
B)Siemens Healthcare Systems
C)Philips
D)Toshiba Medical Systems

Question 25

The first IR commercially available in CT scanners was the Image Reconstruction Image Space in 2009.

Question 26

When implementing IR algorithms into CT clinical practice, it is not important to produce performance evaluations.

Question 27

Please match each of the following IR algorithms to the vendor who introduced it. Answer selections will be used only once.

ASIR-V

A)GE Healthcare Systems
B)Siemens Healthcare Systems
C)Philips
D)Toshiba Medical Systems

Question 28

Model-based IR methods attempt to model the acquisition process in hopes that the artificial image matches the acquired raw data.

Question 29

Please match each of the following IR algorithms to the vendor who introduced it. Answer selections will be used only once.

iDose

A)GE Healthcare Systems
B)Siemens Healthcare Systems
C)Philips
D)Toshiba Medical Systems

Question 30

Statistical methods without modeling use photon counting statistics during the reconstruction process.