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?
1st Generation
2nd Generation
3rd Generation
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.
rotate, translates
translate, rotates
precess, glides
glide, precesses
3rd generation systems incorporate what type of beam geometry?
Pencil Beam
Cone Beam
Electron Beam
Fan Beam
What was the major difference in the configuration between 2nd and 3rd generation CT systems?
The 2nd generation detector array is arranged in a straight line whereas the 3rd generation system's is arranged in a curved arc
The 3rd generation detector array is arranged in a straight line whereas the 2nd generation system's is arranged in a curved arc
The 2nd generation systems used pencil beam geometry whereas 3rd generation systems use electron beam geometry
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?
50 to 100
100 to 200
200 to several thousand
several thousand to 1,000,000
The term “scan” slightly changed meaning with the introduction of 3rd generation systems. Why?
Because the scanner nolonger needed to stop after one rotation and go the other way due to the high tention cables
Because the tube/detector array no longer had to “translate” across the patient
Because images were nolonger scanned one at a time but acquired via spiral CT
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.
Why were 4th generation systems developed?
To replace 3rd generation scanners
As an improvement upon 3rd generation scanners
As an alternative to 3rd generation scanners
Just for heart studies
How fast can a 3rd generation system acquire the data for one image?
Under one second
Under five seconds
Under 10 seconds
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)
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.
True
False
What is the beam geometry of a 4th generation system?
What does nutate mean?
To spin
To angle
To skip
To precess
T/F: Many more detectors are required in 3rd generation scanners than 4th generation scanners.
True
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.
True
False
T/F: 3rd and 4th generation systems use different approaches to achieve similar results.
True
False
T/F: Today there are very few scanners that use 4th generation technology.
True
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.
True
False
In the days before continuous rotation scanners, what transferred the high voltage from the generator to the x-ray tube?
The Flux Capacitor
A 220 Volt 16 gauge wiring harness
A large, bulky, high tension cable
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?
To obtain RF signal in the opposite direction
To prevent the Flux Capacitor from overheating
To maintain even wear on the slip ring bushings
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.
The Flux Capacitor
The Scan Controler
The Slip Ring
The High Voltage Transformer
Why were continuous rotation scanners introduced?
To reduce the dose to patients
To expediate the exam process by reducing scan time
To reduce the wear and tear on the high tension cable
To eliminate the need for the high voltage generator