Renal Vasculature Flashcards
Flow-reducing renal artery stenosis has a peak systolic velocity of…
Greater than 180 cm/s
What signifies a flow-limiting renal artery stenosis (>60% diameter-reducing) ?
A peak systolic velocity > 180cm/s AND A poststenotic signal
True/False
The presence of disease in the contralateral renal artery will have NO effect on the waveform characteristics of a renal artery stenosis.
True
In cases of renal vein thrombosis, the Doppler spectral waveform exhibits what kind of flow?
reverse, blunted, diastolic flow.
Increased venous pressure results in…
Reversed, delayed, diastolic outflow.
Renal artery stenosis exceeding 80% diameter-reduction results in a…
large pressure-flow gradient distal to the lesion.
Doppler signals recorded distal to a thrombosed segment of a renal vein indicate the likelihood of:
Recanalization
Restoration of flow distal to obstructed segments is usually accomplished via…
Recanalization of collateralization
To visualize the mid-to-distal segment of the renal arteries and the kidneys, what patient should the patient be in?
Prone, LLD or RLD
What should be used to identify the accessory renal arteries?
Large Doppler sample volume
(for the low resistance signal)
What can be used to improve the examination of stented renal arteries?
Harmonics imaging
Harmonic imaging is used to improve _________
Resolution & conspicuity of lesions
What can be used to decrease artifact?
Harmonic imaging
Name the four segments of the kidney:
Hilum, Sinus, Medullar, and cortex
When a high-grade renal artery stenosis is present (exceeding 80%), the waveform distal to the lesion will have what kind of peak/rise time?
Delayed systolic peak
The renal-aortic velocity ratio (RAR) should not be used as the primary diagnostic criterion when he patients proximal aortic velocity is:
30 cm/s
The kidney is a (blank) resistance organ
Low resistance
Diastolic flow in the renal artery normally moves…
Forward
What is used to acquire the Doppler waveform from the distal renal artery and its segmental branches?
(Is a component of the indirect renal hilar duplex examination.)
A 0-degree angle of insonation
A poststenotic signal signifies the presence of a…
pressure-flow gradient
What is associated with flow at the site of renal artery stenosis, but not usually with tortuousity of the renal artery?
Poststenotic turbulence
What transducer would be the best choice for performing a renal duplex examination in an adult patient?
- To 5 MHz curved array
What would best improve the accuracy of measuring kidney length?
Averaging three separate measurements
Approximately 9% of patients presenting for real duplex evaluation will have an:
Bifid Left Renal Vein
