Exam (elaborations)
Computed Tomography for Technologists 2nd Edition Exam Reviewed questions with correct answers.
- Course
- Institution
Computed Tomography for Technologists 2nd Edition Exam Reviewed questions with correct answers.
[Show more]
Seller
Follow
Content preview
Computed Tomography forTechnologists 2nd Edition Exam
Reviewed questions with correct
answers.
Which is NOT a synonym for the preliminary/localizer image taken at the start of a CT examination?
A. Topogram
B. Scout
C. Scanogram
D. Spiral ANS - D. Spiral
The ability of a system to differentiate, on the image, objects with similar densities is known as:
A. High contrast resolution
B. Low contrast resolution
C. Spatial resolution
D. Temporal resolution ANS - B. Low contrast resolution
Each two dimensional square of data that make up the CT image is called a:
A. Pixel
B. Voxel
C. Matrix
D. Fragment ANS - A. Pixel
How many pixels are contained in a 1,024 matrix image? A. 1,024
B. 2,048
C. 262,144
D. 1,048,576 ANS - D. 1,048,576
,Beam attenuation can be defined as:
A. The phenomenon by which artifacts result when lower energy photons are preferentially absorbed,
leaving only higher-intensity photons to strike the detector array.
B. Xray energy that is produced from bombarding a substance with fast moving electrons.
C. The ability of the detector to capture transmitted photons and change them to electronic signals.
D. The phenomenon by which an xray beam passing through a structure is decreased in intensity or
amount because of absorption and interaction with matter. ANS - D. The phenomenon by which an xray
beam passing through a structure is decreased in intensity or amount because of absorption and
interaction with matter.
Which of the following is a low attenuation structure:
A. Iodine filled aorta
B. Rib
C. Trachea
D. Calcified arteries ANS - C. Trachea
An object is slightly less dense than water. What is the expected hounsfield measurement?
A. -940
B. -10
C. 50
D. 850 ANS - B. -10
Why does the administration of iodinated contrast media result in an enhanced image?
A. Iodinated contrast material increases the ability of the enhanced structure to attenuate the xray
beam.
B. Iodinated contrast material decreases the average photon energy of the xray beam; therefore more
photons are absorbed by the patient.
C. The administration of contrast material results in a smaller pixel, thereby increasing spatial resolution,
which results in an enhanced image.
D. ANS - A. Iodinated contrast material increases the ability of the enhanced structure to attenuate the
xray beam.
,The xray beam sources for CT produce xray energy that is polychromatic. This means:
A. When viewed by the naked eye, the beam exhibits many different colors.
B. It produce, as a byproduct, a substance known as polychlorinated biphenyl.
C. Photons contained in the beam are all of the same wavelength.
D. The beam comprises photons with varying energies. ANS - D. The beam comprises photons with
varying energies.
An object that appears on the image but is not present in the object scanned is called a/n:
A. Artifact
B. Anomaly
C. Shadow
D. Ghost ANS - A. Artifact
Which is an advantage of filtering the xray beam?
A. Filtering reduces the anode heat load
B. A filtered beam produces images with substantially less quantum mottle
C. Filtering the beam prevents energy from being converted to heat, therefore 100% of the energy is
converted to xrays.
D. Filtering reduces the radiation dose to the patient. ANS - D. Filtering reduces the radiation dose to the
patient
Scan thickness is primarily important for the part it plays in:
A. Noise reduction
B. The contrast scale
C. Detector aperture opening
D. Volume averaging ANS - D. Volume averaging
You are working with the radiologist to establish examination protocols for your department. Which of
the following is a logical consideration when determining an appropriate slice thickness for studies of
the internal auditory canal?
, A. Because the auditory ossicles are quite small, a thin slice will be necessary to reduce the chance that
volume averaging will obscure their appearance on the image.
B. The appropriate slice thickness will vary considerably from patient to patient. Therefore, each
technologist should be free to adjust the slice thickness as he or she deems necessary for the particular
patient.
C. A slice thickness of 5 to 7mm is adequate because the structures of interest are not particularly small
and the examination is most often ordered as a screening study for asymptomatic patients.
D. The thickest slice available should be used to reduce the radiation dose to the corneas. ANS - A.
Because the auditory ossicles are quite small, a thin slice will be necessary to reduce the chance that
volume averaging will obscure their appearance on the image.
How many CT numbers are assigned to each pixel in the image matrix?
A. One half the number of all values recorded from the detector array
B. One
C. The number of HU per pixel is one tenth the display field of view
D. Two values for a 256 matrix; 4 values for a 512 matrix ANS - B. One
Which is another name for raw data?
A. Image data
B. Scan data
C. Reconstructed data
D. Displayed data ANS - B. Scan data
When in the anatomic position, the arms are:
A. raised above the head, palms backwards
B. crossed over the chest, palms on opposite shoulders
C. down by the sides, palms forward
D. by the sides, elbows bent, palms backward and resting on hips ANS - C. down by the sides, palms
forward
Which of the following components is NOT housed within the gantry?
The benefits of buying summaries with Stuvia:
Guaranteed quality through customer reviews
Stuvia customers have reviewed more than 700,000 summaries. This how you know that you are buying the best documents.
Quick and easy check-out
You can quickly pay through credit card or Stuvia-credit for the summaries. There is no membership needed.
Focus on what matters
Your fellow students write the study notes themselves, which is why the documents are always reliable and up-to-date. This ensures you quickly get to the core!
Frequently asked questions
What do I get when I buy this document?
You get a PDF, available immediately after your purchase. The purchased document is accessible anytime, anywhere and indefinitely through your profile.
Satisfaction guarantee: how does it work?
Our satisfaction guarantee ensures that you always find a study document that suits you well. You fill out a form, and our customer service team takes care of the rest.
Who am I buying these notes from?
Stuvia is a marketplace, so you are not buying this document from us, but from seller Professorkaylee. Stuvia facilitates payment to the seller.
Will I be stuck with a subscription?
No, you only buy these notes for $23.99. You're not tied to anything after your purchase.
Can Stuvia be trusted?
4.6 stars on Google & Trustpilot (+1000 reviews)
67163 documents were sold in the last 30 days
Founded in 2010, the go-to place to buy study notes for 14 years now