CT Registry Review - System Operation & Components -Question Set 2
Questions 26-50
Choose the Correct answer for each question in the quiz! References
When was the 1st CT System commercially introduced?
1987
1998
1973
1975
How many Generations of CT Systems are there?
Two
Five
Ten
Four
First Generation CT Systems generated a thin, focused x-ray beam called what?
Thin Fan Beam
Pencil Beam
Lazer Beam
Jim Beam
How many detectors were incorporated in the 1st Generation CT Systems?
one
two
three
four
The tube/detector configuration in a 1st Generation Scanner scanned across the patient’s body in a linear path before rotating and repeating. What is this called?
Interpalation
Translation
Forier Transmition
Acquisition
In a 1st generation scanner, what did you call the series of measurements that was collected as the tube/detector assembly translated across the patient?
An acquisition
A scan cycle
A flat scan
A projection
What is the 1st generation definition of a Projection?
1st Generation: What happens next after a complete translation from one side of the patient to the other?
The tube/detector assembly rotates about the patient 5 degrees and another translation commences so that another “Projection” can be measured.
The tube/detector assembly rotates about the patient 1 degree and another translation commences so that another “Projection” can be measured.
The tube/detector assembly rotates about the patient 1 degree and another translation commences so that another “Acquisition” can be measured.
The tube/detector assembly rotates about the patient 1 degree and another translation commences so that another “Acquisition” can be measured.
How many different projections were needed in a 1st generation system in order to construct and image?
180
360
800
1000
What was the shortest possible scan time per image with a 1st Generation system?
1 min. per image
5 min. per image
10 min. per image
20 min. per image
Since 1st generation scanners were so slow, imaging was limited to what part of the body?
Extremeties
Neck
Head
Chest
Why was CT imaging limited to the head in first generation scanners?
Because Computer technology at that time could not handle the incresed data calculations necissary.
Because x-ray tubes at that time could not handle the heat load necissary for larger body parts.
Because reconstruction algorythms for larger body parts had not yet been developed.
Because patient motion could be more easily controlled
Select four key aspects of 1st generation CT Scanners.
2nd generation CT Systems used an x-ray beam that had a shape similar to a/an ______ _____ ___.
2nd generation systems are referred to as having _________________ Geometry.
pencil beam
cone beam
lazer beam
fan beam
2nd generation CT Systems contain a/an _______ of detectors referred to as a/an ___________________.
bank / Data Acquisition System
group / detector array
selection / photo multiplier
number / flat pannel
About how many detectors comprised the detector array in 2nd generation scanners?
About 30
About 100
About 250
About 750
What was the purpose of the added detectors (detector array) and the fan beam geometry in the 2nd generation design?
To improve spatial resolution
To reduce radiation dose to the patient
To reduce the amount of time required to collect data
To eliminate artifact produced by pencil beam geometry
How much faster could a 2nd generation scanner collect the required data compared to a 1st generation scanner?
Twice as fast
Five times faster
Ten times faster
Onehundred times faster
T/F: In regards to 2nd generation CT Systems, the tube/detector assembly still translated across the patient during the collection of a “projection” of data.
True
False
After a “projection” of data is obtained in a 2nd generation CT System, the tube/detector rotates typically ____________ covering an arc of __________ around the patient.
5 degrees or more / 180 degrees
5 degrees or more, 360 degrees
10 degrees or more, 180 degrees
10 degrees or more, 360 degrees
What was the scan time for a single image in a 2nd generation scanner?
Approximately 5 seconds
Approximately 20 seconds
Approximately 60 seconds
Approximately 5 min.
What single aspect of 2nd generation scanners led to applications outside the head?
"Fan Beam" geometry
Increased number of detectors
Reduced scan time
Improved algorithms
What were the 2 most important features of 2nd generation scanners which quickly made 1st generation systems obsolete?
Select the four key aspects of 2nd generation CT Systems.