Duplex/color flow imaging (abdomen) Flashcards
A dilation > 3cm or an increase in diameter of 50% greater than original artery.
Aorto-iliac arteries aneurysm
Evaluate vessels for stenosis, status of bypass grafts, aneurysmal disease
Aorto-iliac vessels
Majority of abdominal aortic aneurysms (AAA) are
atherosclerotic and intrarenal
Rupture of the aortic aneurysm; embolization of the peripheral aneurysms (could cause blue toe) Trash foot
Most frequent complication with aneurysm
An enzyme that converts angiotensinogen to angiotensin
(related to renovascular hypertension)
Renin
Many of these patients with present with hypertension (controlled or not controlled)
Renal artery studies
Renal arteries and kidney arteries are normally more ____ resistant
Low (above baseline diastole)
The aorta is usually _______ resistant
Higher
If a AAA is detected you cannot use
Renal to aortic ratio (RAR)
Highest renal artery divided by Aorta PSV
Renal to aortic ratio (RAR)
If aortic PSV is > 90 cm/s or < 40 cm/s you cannot use
Renal to aortic ratio (RAR)
Abnormal (RAR)
> 3.5 (suggests > 60% diameter reduction)
Normal (RAR)
< 3.5
> 180 - 200 cm/s that is followed by post - stenotic turbulence
Too fast!
Normal pole length of a kidney is
10-12 cm.
End diastolic ratio
Parenchymal resistance ratio (PR) normal is
End Diastolic V divided by
PSV
> 0.2
End diastolic ratio
Parenchymal resistance ratio (PR) abnormal is
< .2
Resistivity Index
PSV- EDV divided by
PSV
Normal
< .8 (low resistance)
Resistivity Index
PSV- EDV divided by
PSV
abnormal
> .8
Patients presenting with a history of dull, achy or crampy abdominal pian 15-30 minutes after meals are suspect for
Mesenteric ischemia
Chronic and acute mesenteric ischemia is difficult to diagnose and require a
Arteriogram
Obtain the PSV and EDV of the following: (longitudinal approach)
Celiac artery (may use TX approach)
Proximal, mid, distal SMA
IMA
Aorta (check for abnormalities)
Technique
High resistance flow pre-prandial
Converts to lower resistance flow post-prandial
Normal velocities range from 110-177 cm/s
Abnormal velocities PSV > 275 cm/s predicts > 70% diameter reduction
SMA
Low resistance flow pre- prandial (always)
Remails low resistance post - prandial (unaffected by eating)
Normal velocities range from 50-160 cm/s
Abnormal velocities PSV > 200 cm/s predicts > 70% diameter reduction
Celiac Artery
Pre - prandial high resistant waveform remains high resistant post - prandial which suggests distal mesenteric disease
Abnormal SMA
Marginal Artery of the colon (AKA marginal A. of Drummond)
Arc of Riolan
IMA two possible connections
Extrinsic compression of celiac artery origin by the median arcuate ligament of the diaphragm
Celiac band syndrome
Documenting patency of portal vein, hepatic veins, IVC and hepatic artery
Pre and post operative eval liver transplant
Example of grayscale signs of rejection for renal transplant
Increased renal transplant size
Transplanted RA anastomosed to EIA or IIA; transplanted RV anastomosed to EIV
Renal transplant
Increased arterial resistance
Acute rejection (renal transplant)
What is consider the most reliable method for rejection diagnosis for kidney transplant patients
Biopsy
