- Renal Artery Stenosis: Facts
- The cause of hypertension in adults in less than 5% of cases
- Potentially curable
- Diameter stenosis greater than 50% often hemodynamically significant - “ MDCT is a minimally invasive study for evaluating the renal arteries in normal individuals and patients with suspected renal pathology. The ability to obtain thin sections and cover a large area may improve the detection and characterization of renal artery anomalies and disease.”
Multidetector Computed Tomographic Evaluation of the Renal Artery
Pannu HK, Fishman EK
Abdom Imaging 27:611-619 (2002) - Renal Artery Fibromuscular Dysplasia (FMD): Facts
-Younger patient
- Predominately female population
- “String of pearls” appearance (due to multiple stenosis) are classic appearance - Fibromuscular Dysplasia: Classification
- Medial fibromuscular disease
- 65-70% of cases
- String of beads appearance
- Perimedial (subadventitial form)
- 15-20% of cases
- Aneurysm formation or focal stenosis - Fibromuscular Dysplasia: Classification
- Medial hyperplasia
- 8-10% of cases
- No classic radiologic appearance
- 1-2% of cases
- Isolated intimal or adventitial involvement
- “ More recently, in a study comparing 4-slice MDCT to digital subtraction angiography, the sensitivity and specificity for all degrees of renal artery stenosis were 100% and 98.6%, respectively. For stenosis greater than 50%, sensitivity was 100% and specificity 97.3%.”
Computed Tomography Angiography of the Renal and Mesenteric Vasculature: Concepts and Applications
Johnson PT, Fishman EK
Seminars in Roentgenology
2011: 115-124 - CT Angiography of the Renal Arteries: Fibromuscular Dysplasia
-Causes less than 10% of cases of renal artery stenosis
-More common in young or middle aged woman
-Associations include smoking, hormones, and vasa vasorum disorders
-FMD may appear as a “string of beads” appearance
-May be bilateral in 71% of cases when symptomatic - CT Angiography of the Renal Arteries: Renal Artery Stenosis
Etiology
-Atherosclerotic disease (90%)
-Age
-Diabetes
-Aortoiliac occlusive disease
-Hypertension
-Presence of coronary artery disease - CT Angiography of the Renal Arteries: Renal Artery Stenosis
-Reconstruction of data required to define and quantify presence and degree of stenosis
-MIP can lead to overcalling the degree of stenosis
-VRT when used correctly has a 95-100% accuracy
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