CT Registry Review - System Operation & Components

CT Registry Review - System Operation & Components - Question Set 3

Questions 51-75

Choose the Correct answer for each question in the quiz!
References

The vast majority of CT scanners in operation and production today utilize which generation of CT technology?
1. 1st Generation
2. 2nd Generation
3. 3rd Generation
4. 4th Generation
When were scanners with 3rd generation technology first intorduced?
The tube/detector array in a 3rd generation system does not _________, like 1st and 2nd generation scanners, but instead ______ around the patient.
1. rotate, translates
2. translate, rotates
3. precess, glides
4. glide, precesses
3rd generation systems incorporate what type of beam geometry?
1. Pencil Beam
2. Cone Beam
3. Electron Beam
4. Fan Beam
What was the major difference in the configuration between 2nd and 3rd generation CT systems?
1. The 2nd generation detector array is arranged in a straight line whereas the 3rd generation system's is arranged in a curved arc
2. The 3rd generation detector array is arranged in a straight line whereas the 2nd generation system's is arranged in a curved arc
3. The 2nd generation systems used pencil beam geometry whereas 3rd generation systems use electron beam geometry
4. The 3rd generation systems used pencil beam geometry whereas 2nd generation systems use electron beam geometry
How many detectors are contained in a 3rd generation systems detector array?
1. 50 to 100
2. 100 to 200
3. 200 to several thousand
4. several thousand to 1,000,000
The term “scan” slightly changed meaning with the introduction of 3rd generation systems. Why?
1. Because the scanner nolonger needed to stop after one rotation and go the other way due to the high tention cables
2. Because the tube/detector array no longer had to “translate” across the patient
3. Because images were nolonger scanned one at a time but acquired via spiral CT
4. Because the use of a dual scout was nolonger necissary
What is today’s definition of a “scan”?
Select the four key aspects of a 3rd generation CT system from the list below.
1. Pencil Beam
2. Fan Beam
3. Cone Beam
4. Multiple detectors along a straight line
5. Multiple detectors aranged in a curved arc
6. A ring of detectors completely surrounding the patient
7. Total scan time faster than 1 second per image
8. Total scan time faster than 5 seconds per image
9. The tube/detector assembly translates accros the patient, rotates 1 degree and then translates again
10. The tube/detector assembly rotates around the patient ( without translating)
Why were 4th generation systems developed?
1. To replace 3rd generation scanners
2. As an improvement upon 3rd generation scanners
3. As an alternative to 3rd generation scanners
4. Just for heart studies
How fast can a 3rd generation system acquire the data for one image?
1. Under one second
2. Under five seconds
3. Under 10 seconds
4. Under one millisecond
Why was the curved detector array contained in 3rd generation CT systems an improvement over 1st and 2nd generation designs? (select all that apply)
1. It improved the reproducibility of the projection data measured across the array
2. Because the increased number of detectors improved the spatial resolution in the resultant images
3. It minimized certain artifacts that were common in 2nd generation systems
4. Fewer detector elements were needed which decreased overall cost and the number of necissary calculations required durring image reconstruction
T/F: In a 4th generation CT system, the detectors do not travel with the tube but instead form a complete ring around the gantry in a circular configuration, which angles or nutates during the scanning process.
1. True
2. False
What is the beam geometry of a 4th generation system?
What does nutate mean?
1. To spin
2. To angle
3. To skip
4. To precess
T/F: Many more detectors are required in 3rd generation scanners than 4th generation scanners.
1. True
2. False
T/F: 4th generation systems did not necessarily represent a design which was more advanced than 3rd generation systems or that offered improved clinical benefits.
1. True
2. False
T/F: 3rd and 4th generation systems use different approaches to achieve similar results.
1. True
2. False
T/F: Today there are very few scanners that use 4th generation technology.
1. True
2. False
T/F: In the early days of 3rd generation systems, the high voltage generator was large and heavy and was safely fastened to the floor in the exam room.
1. True
2. False
In the days before continuous rotation scanners, what transferred the high voltage from the generator to the x-ray tube?
1. The Flux Capacitor
2. A 220 Volt 16 gauge wiring harness
3. A large, bulky, high tension cable
4. A set of Anode Leads
In the early days of 3rd generation scanners, before the invention of continuous rotation scanners, why was it necessary to stop the gantry frame from rotating at the end of every scan and then reverse the direction of the gantry frame’s rotation for the next scan?
1. To obtain RF signal in the opposite direction
2. To prevent the Flux Capacitor from overheating
3. To maintain even wear on the slip ring bushings
4. To prevent the high-tension cable going from the High Voltage Generator to the tube from winding up
Most continuous rotation scanners use ______________ technology.
What do we call the large rotating ring which surrounds the gantry aperture and, by means of electrical brushes, conveys electrical power and data to the components mounted on the rotating ring.
1. The Flux Capacitor
2. The Scan Controler
3. The Slip Ring
4. The High Voltage Transformer
Why were continuous rotation scanners introduced?
1. To reduce the dose to patients
2. To expediate the exam process by reducing scan time
3. To reduce the wear and tear on the high tension cable
4. To eliminate the need for the high voltage generator