What CT artifact occurs when the object being scanned is outside the scan-field-of-view (SFOV)?
out of field
partial volume averaging
What is the purpose of the slip-ring technology employed in modern CT scanners?
capacity for continuous acquisition protocols
employ single data acquisition protocols
increase tube loading
decrease temporal resolution
Which of the following scientist theory states the sampling rate must be at least twice the highest analog frequency component?
What ligament extends from the anterior part of the tibial spine and attaches to the posterior part of the medial surface of the lateral femoral condyle?
anterior cruciate ligament
lateral collateral ligament
posterior cruciate ligament
medial collateral ligament
Name an advantage of utilizing the Fourier transform for image reconstruction:
manipulation of data in the spatial frequency domain
manipulation of data in the spatial location domain
calculating the intensities along the ray sum
calculating the CT number of the given intensities
Patients with liver dysfunction or cardiac failure, but have normal renal function, metformin should be discontinued at the time of an examination or procedure using intravenous iodinated contrast media and withheld for how many hours post injection?
should not receive iodinated contrast media
How should lead shielding (if being utilized) be placed on the patient during a CT examination of the brain?
under the patient’s body region not being examined
under and over the patient’s body region not being examined
over the patient’s body region
no need to use shielding for a CT examination
This figure demonstrates which of the following 3D techniques?
A particular CT image has a matrix size of 512^2 and a field-of-view (FOV) of 360 mm, what is the pixel area?
Which of the following refers to a method by which the patient is systematically scanned by the x-ray tube and detectors to collect enough information for image reconstruction?
Which of the following pathological conditions is a major risk factor for stroke and can lead to brain damage?
carotid artery stenosis
salivary stone obstruction
jugular vein thrombosis
When images are transmitted to a PACS system or other devices, they are encrypted and compressed during transportation for speed and security. What type of compression is required by HIPAA for the transmission of medical data?
Which of the following glands are depicted as high-attenuation structures on CT images?
What is the pitch having a table feed of 15.36, a gantry rotation of 0.3 seconds, and a detector collimation of 128 × 0.3 mm?
What is the purpose of performing an unenhanced CT scan of the liver?
to demonstrate hepatocellular carcinoma
to demonstrate hepatomas
to demonstrate cirrhosis
to demonstrate fatty infiltrates
Which of the following refers to the ability of the CT detector to capture, absorb, and convert x-ray photons into electrical energy?
Which of the following is not an advantage of today’s iterative reconstruction algorithm?
increase in kVp
reduction in mAs
improves image quality
Contrast resolution is superior with CT examinations principally because of what feature?
high-pass convolution kernel
Which of the following statements is true concerning the celiac trunk?
it is superior to the renal arteries on the abdominal aorta
it is the only unpaired visceral branch of the aorta
it divides into the gastric, splenic, and mesenteric arteries
it branches from the aorta at the level of L2/L3 vertebral level
Networking or connectivity became an essential aspect when radiology departments were urged to become filmless. Which of the following area networks covers an area of a few city blocks to the area of an entire city?
Metropolitan area network (MAN)
Local area network (LAN)
Wide area network (WAN)
World wide web (WWW)
Which of the following is a potential complication from the use of barium sulfate as an oral contrast agent?
The primary vendors of CT systems all have systems available which will reduce radiation dose. Which of the following is a commonplace technique that optimizes the dose to the patient while maintaining constant image quality?
automatic tube current modulation
dual energy scanning
hybrid detector array
Which of the following pathological infections cause damage to the heart valves and valve leakage?
The floor of the third ventricle is formed by what organ of the brain?
A particular CT image possesses a pixel size of 0.68 mm; what is the DFOV that was used during reconstruction?
When a CT x-ray beam experiences beam hardening, what happens to the mean photon energy of the beam?
beam hardening and beam energy are not related
In what CT scanner does cone beam artifacts occur?
third generation with ≥16 detector channels
fourth generation with ≥16 detector channels
third generation with single detector
What CT imaging plane is the most common entity for identifying pars defects?
3D-shaded surface rendering
Which of the following detector array systems consist of several solid-state small detectors of the same dimension that are arranged in rows of identical thickness?
A CT water phantom was scanned and the linear attenuation coefficient of a particular pixel on the image measured 0.0004; what does this coefficient represent in terms of structures?
Which of the following is a characteristic of raw data?
is the unprocessed computer data in the form of binary numbers
can be sent to a laser printer for hard-copy viewing
undergoes corrections for errors that occurred
known as scan data
What is the range of CT numbers if the window width is 2,000 and the window level is 700?
1,700 to –300
-1,700 to 300
−2,300 to 1,650
2,300 to -1,650
Which of the following QA test requires the operator to place 5 ROIs within a homogeneous water phantom?
The Modulation Transfer Function (MTF) can be used to estimate spatial resolution at which of the following frequencies?
at all spatial frequencies
at high spatial frequencies
at low spatial frequencies
by converting an LSF to an ERF
Which of the following reconstruction algorithms improves the appearance of contrast resolution?
Which of the following combinations will produce an image with the best spatial resolution?
small pixels and thin slice width
small pixels and thick slice width
large pixels and thick slice width
large pixels and thin slice width
Which of the following is located in the retroperitoneal space?
When performing an invasive procedure, it is imperative to check the patient’s INR results. Which of the following INR ratios is appropriate for a patient on anticoagulant medication?
Which of the following are recommended by the Center for Devices and Radiological Health as a CT dose descriptor?
ionization chamber measurements
Peritoneal ligaments serve to connect organs with another organ or to the abdominal wall; what is the function of the hepatorenal ligament?
connects the liver to the kidney
connects the stomach to the liver
connects the gall bladder to the hepatic flexure
connects the stomach to the diaphragm
Which chamber of the heart comprises the largest portion of the anterior surface of the chest and receives deoxygenated blood from the right atrium and forces it into the pulmonary trunk for transportation to the lungs?
Name the space between the dura mater and arachnoid meningeal layers: