QA, Safety & SPI Flashcards
The ability of a test to detect disease when it IS present
sensitivity
When clot is present on a venogram, how does it appear on the image
“empty” vein with no contrast opacification
When evaluating heavily calcified arteries, what system settings should be increased to improve the demonstration of flow in the vessels
persistence and sensitivity
What imaging parameter is responsible for the ability to resolve two atheromas that are side by side in an artery
lateral resolution
When venous flow is slow, echogenic particles can be seen near the walls and in the valvular sinus. This phenomenon is called
spontaneous contrast
What system setting would result in false-positive findings for reflux in the GSV
high color persistence settings
How to calculate sensitivity
total number of correct positive diagnoses divided by the total number of truly positive tests
The recommended sample size for PW doppler evaluation of an artery is
1-1.5mm
What type of image resolution makes it possible to differentiate the intimal media thickness from the outer arterial wall
axial
The ability of a test to rule out disease when it is NOT present
specificity
A proximal femoral artery stenosis will cause the ________ in the mid femoral to increase
acceleration time to increase
Vessel wall and plaque morphology are best evaluated in 2D when the beam is at what incident angle to the vessel
90 degrees
_________ is the gold standard in testing fr arterial disease
angiography
What is the gold standard evaluation technique for renal artery stenosis
angiography
The __________ of a test is calculated by the number of correctly diagnosed negative exams by the total number of true negative exams
specificity
What information from a angiography report can be correlated with the ultrasound results
diameter stenosis
What modality is preferred to diagnose an aortic dissection
CTA
If the acceleration time is >140ms in both common femoral arteries then
aortic disease is suspected
The _______ of a test is calculated by the total number of correct diagnoses divided by the total number of diagnoses made
accuracy
Pulsatility Index can be used to describe
the amount of variation in the velocity during the cardiac cycle
What is the framingham risk score
gender specific criteria for estimation of 10 year risk of cardiovascular disease
Abdominal Doppler exams are usually best perofrmed with a frequency of _____ MHz and a lower extremity arterial duplex exams are usually best performed with a frequency of _____ MHz
2-4, 5-7
What modality is preferred to diagnose fibromuscular dysplasia in the circle of willis
angiography
What would be the probe frequency of choice for a TCD exam
2MHz
By dividing the pulsatility index proximal to a stenosis by the pulsatility index from distal to a stenosis, you can evaluate the
damping factor
When the velocity of flow is calculated for vessels evaluated on a TCD exam, a ________ degree angle of incidence is assumed
0
If new research shows that the minimum velocity criteria used to diagnose >60% renal artery stenosis is actually 225cm/s, not 180cm/s, how will this affect the accuracy of the renal doppler exam
increase will vary with patient population
If new research shows that the minimum velocity criteria used to diagnose >60% renal artery stenosis is actually 225cm/s, not 180cm/s, how will this affect the negative predictive value of the exam
decrease will vary with patient population
The Appropriate Use Criteria were developed while considering
vascular ultrasound or physiologic testing by itself as a reasonable exam choice
What is the gold standard method of diagnosing temporal arteritis
biopsy
