1.3 Renal Artery Stenosis/Occlusion/Thrombosis Flashcards
What does ACUTE Renal vein thrombosis present with (2)
- Pain
2. Hematuria
What will you see on Ultrasound with ACUTE RV thrombosis? (4)
- Enlarged kidney
- Altered parenchymal echogenicity
- Enlarged renal vein
- Absent Doppler signal
What does CHRONIC Renal vein thrombosis present with ?
- Asymptomatic
OR
1) Nephrotic syndrome OR 2) hematuria
What 2 things may block the vein?
- Intraluminal thrombus
2. Extrinsic compression
What is the most common reason for RV thrombosis?
Primary renal disease
What disease can RV thrombosis cause?
Parenchymal disease
What can Parenchymal disease lead to?
Renal failure
Why may venous flow still be seen in the kidneys with RV thrombosis?
Collateral vessels
What can stenosis or occlusion cause?
renal ischemia
What can renal ischemia lead to?
Hypertension
Stenosis causes __________damage
Parenchymal Damage
What located the renal arteries and detects flow disturbances indicating stenosis?
Color Flow
What quantifies stenosis severity?
Spectral Doppler
What % diameter reduction suggests a significant stenosis?
50-60%
What type of patients should Renal artery stenosis be investigated in?
Young with hypertension
Uncontrollable hypertension
Renal insufficiency
Inconsistant kidney sizes
What is the most common cause of stenosis in a patient > 50 years of age?
Atherosclerosis
What is the most common cause of stenosis in a patient < 40 years of age?
Fibromuscular Dysplasia (FMD)
Other causes of stenosis (4)
- Vasculitis
- Neurofibromatosis
- Congenital bands
- Extrinsic compression
What is the normal PSV for Renal Arteries?
74-127 cm/sec
What is PSV that indicates a significant stenosis in Renal Arteries?
> 180 cm/sec
What is the Renal Artery /Aorta Ratio indicating a significant stenosis?
> 3.5
What waveform suggests renal disease?
Dampening of intrarenal arteries
What acceleration time is abnormal indicating a renal stenosis of >60%?
> 0.07 seconds
What is the most correctable cause of hypertension?
Renal Artery Stenosis
What are often used to preserve patency and prevent occlusions?
Stents
What are the 4 features of SEVERE Renal artery stenosis
- Decreased kidney size (atrophy)
- Renal infarct (hypoechoic area within kidney)
- Renal hypoperfusion
- Narrowed artery with area of aliasing and increased PSV
What are the 4 features of SEVERE Renal artery OCCLUSION
- Decreased kidney size (atrophy)
- No main artery is visualized
- Absent flow/low
- Dampened intrarenal flow
Other conditions that can cause increased resistance within the kidney include (2)
- UT obstruction
2. Acute and chronic parenchymal disease
When may a false postitive diagnosis of RA occlusion happen?
With poor visualization of artery and kidney
