Deck 16: Positron Emission Tomographycomputed Tomography Scanners

Question 1

Sodium iodide and bismuth germinate are newer scintillating materials that have reasonably high detection efficiency.

Answer 1

False

Question 2

Which of the following only looks at the ratio of events acquired with and without the patient in place?

A)averaged attenuation correction
B)measured attenuation correction
C)scanned attenuation correction
D)total attenuation correction

Answer 2

measured attenuation correction

Question 3

One approach to reducing scatter includes introducing __________ between detection rings.

A)antiscatter grids
B)filtration
C)absorbing septa
D)scatter shields

Answer 3

absorbing septa

Question 4

A transmission scan is first acquired without the patient in place, which is called a:

A)blank scan
B)first scan
C)review scan
D)scout scan

Question 5

The probability of detecting the photons from an annihilation event from one center of an object is less than that for an event on the periphery.

Question 6

A modern positron emission tomography scanner might contain tens of thousands of small scintillating detectors.

Question 7

¹⁸F-2- fluoro-2-deoxy-D-glucose (FDG) positron emission tomography has not been useful in the localization of epileptic seizures.

Question 8

The use of contrast media in computed tomography can lead to artifacts in the reconstructed positron emission tomography data.

Question 9

An atom that has too many protons or too many neutrons or they are configured in such a way so as to render the nucleus unstable, is said to be a(n):

A)alpha particle
B)beta particle
C)radioactive atom
D)gamma atom

Question 10

The ring diameter of most clinical positron emission tomography scanners is about:

A)1 cm
B)2 cm
C)1 m
D)2 m

Question 11

The crystals in the construction of a positron emission tomography scanner's detectors are:

A)cadmium detectors
B)helium gas detectors
C)scintillation detectors
D)xenon gas detectors

Question 12

Another approach to attenuation correction in positron emission tomography is to use the data from a magnetic resonance imaging scan that are registered to the positron emission tomography data.

Question 13

Radioactive fluorine can be chemically substituted for a: I. hydrogen atom
II) hydroxyl group
III) deoxyglucose

A)I and II
B)II and III
C)I and III
D)I, II, and III

Question 14

All of the following are scintillating materials used in PET detectors except:

A)bismuth germanate
B)calcium tungstate
C)gadolinium oxyorthosilicate
D)sodium iodide

Question 15

Positron emission tomography with ¹⁸F-2- fluoro-2-deoxy-D-glucose (FDG) is a useful tool in the initial diagnosis, staging, and follow-up of lung cancer.

Question 16

The availability of interplane septa allows for the acquisition of positron emission tomography data in two-dimensional mode, which substantially reduces the amount of interplane scatter.

Question 17

If the nucleus contains too many protons, it may emit a: I. positive beta particle
II) positron
III) proton

A)I and II
B)II and III
C)I and III
D)I, II, and III

Question 18

Which of the following can reduce noise in the final reconstructed positron emission tomography images? I. use of image segmentation
II) use of a single photon rather than a positron-emitting source
III) use a special noise filter

A)I and II
B)II and III
C)I and III
D)I, II, and III

Question 19

A positron has the same mass as an electron but has a positive rather than a negative charge.

Question 20

In emission imaging an external, photon emitting source rotates about the patient to acquire a(n):

A)emission scan
B)review scan
C)scout scan
D)transmission scan

Question 21

The most commonly used radiopharmaceutical for positron emission tomographic imaging is:

A)(¹⁵O carbon monoxide)
B)(¹³N ammonia)
C)(¹¹C methionine)
D)(¹⁸F-2-fluoro-2-deoxy-D-glucose (FDG))

Question 22

All of the following are limitations of positron emission tomography/computed tomography technology except:

A)anatomical correlation
B)increased expense
C)increased radiation dose
D)potential attenuation artifacts

Question 23

Clinical examples of positron emission tomographic imaging include: I. cardiac studies
II) epilepsy studies
III) oncology studies

A)I and II
B)II and III
C)I and III
D)I, II, and III

Question 24

When using FDG for a whole body scan, the uptake waiting period is usually:

A)15-45 minutes
B)30-50 minutes
C)45-90 minutes
D)60-120 minutes

Question 25

A disadvantage of using isotopes such as ¹⁵O, ¹³N, and ¹¹C are their:

A)long half-lives
B)short half-lives
C)long persistence
D)short persistence