- “ 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 - Renal Artery Aneurysms: Treatment
-Surgery for aneurysms over 2 cm in size
-Stents can be placed in aneurysms especially those under 2 cm
-Surgery for aneurysms over 1 cm may be indicated with risk factors of hypertension, renal artery stenosis or woman of child bearing age - Renal Artery Aneurysms: Facts
-Most common location is the main renal artery bifurcation or main renal artery (60%)
-May be multiple in up to 25-33% of patients and may be bilateral in 19% of cases
-Complications include hypertension, rupture, renal arterial thrombosis, infarction by distal embolization and AV fistula
-Risk of rupture increases during pregnancy and with increasing aneurysm size - Renal Artery Aneurysms: Common Associations
-Hypertension
-FMD
-Atherosclerosis
-Extrarenal aneurysms
-Arteritis
-Marfan’s syndrome
-Ehlers Danlos syndrome
-Neurofibromatosis
-Smoking - “ Studies using angiography have revealed that 3.8%-6.6% of potential renal donors have fibromuscular dysplasia (FMD), which was bilateral in 43% to 71%. Atherosclerotic lesions were much less common, identified in 2%.”
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: Renal Donor Evaluation
-Number and location of the renal arteries including presence of prehilar branching
-Detection of renal artery stenosis and fibromuscular dysplasia (FMD)
-Presence of renal mass or other important renal findings (horseshoe kidney, scarring of the kidney)
-Renal vein and collecting system also evaluated on venous and delayed topogram - CT Angiography of the Renal Arteries: Protocols
-Images reconstructed with narrow collimation (.75 mm) reconstructed at .5 mm intervals
-All datasets analyze with a combination of axial, multiplanar (coronal and sagittal planes) and 3D rendering (volume rendering (VRT) and maximum intensity projection (MIP)) - CT Angiography of the Renal Arteries: Protocols
-Phases required depend on the application with two phases usually necessary
-Contrast injection rate is 4-5 cc/sec with contrast volumes in the 80-120 cc volume range
-Contrast used is Omnipaque-350 or Visipaque-320 depending on the patients creatinine or GFR levels
-Arterial phase imaging is usually with a 25-30 second delay and nephrographic phase is at 55-60 seconds - CT Angiography: Renal Applications
-Renal donor evaluation
-Renal artery stenosis
-Renal artery aneurysm - Fibromuscular Dysplasia (FMD): Facts
- Involves mid and distal vessels (not proximal)
- Results in areas of stenosis and dilatation of small and mid size vessels
- Cause of hypertension in females under age 40
- Fibromuscular Dysplasia: Facts
- Cause of hypertension in younger population
- More common in woman
- Most common form is medial fibromuscular disease which occurs in 70% of cases
- "String of Beads" appearance is classic
- "Laparoscopic donor nephrectomy has become the accepted method of harvesting the kidney at many institutions because of multiple advantages over open donor nephrectomy. Spiral computed tomographic (CT) angiography provides accurate information of renal vascular anatomy and has become an accepted method of preoperative evaluation of potential laparoscopic renal donors."
MDCT Angiography of Living Laparoscopic Renal Donors Kawamoto S, Fishman EK
Abdom Imaging 2006.
- The Bosniak Renal Cyst Classification System
- Category I
- Category II
- Category IIF
- Category III
- Category IV
- What is a Bosniak IIF?
- Cysts with multiple septae with minimal thickening or calcification which is thick and nodular or intrarenal non-enhancing high density (>3cm) lesion
- These lesions are felt to be benign and routine follow-up advised
- Erdheim-Chester Disease: Facts
- Rare form of non-Langerhans cell histiocytosis
- Characterized by tissue infiltration by foamy histiocytes
- Usually in patients over age 40
- Can be life threatening
- Erdheim-Chester Disease: Facts
- Renal and perirenal involvement in up to 29% of cases
- May encase the thoracic or abdominal aorta (looks like retroperitoneal fibrosis)
- Cardiac infiltration may be endocardial, myocardial or pericardial
- Perinephric Mass: Differential Dx
- Tumors
- Fluid
- Inflammation
- Proliferative diseases
- Perinephric Mass: Differential Dx
- Tumors
- Renal cell carcinoma
- Lymphoma
- Metastases (melanoma)
- Retroperitoneal tumors by direct extension
- Perinephric Mass: Differential Dx
- Fluid
- Hematoma
- Urinoma
- Abscess
- Pancreatic pseudocyst
- Perinephric Mass: Differential Dx
- Proliferative diseases
- Extramedullary hematopoiesis
- Retroperitoneal fibrosis
- Rosai-Dorfman disease
- Erdheim-Chester disease
- "In conclusion, multidetector row CT enables highly accurate assessment of the renal anatomy in living donor candidates."
Assessment of 100 Live Potential renal Donors for Lapatoscopic Nephrectomy with Multidetector Row Helical CT
Holden A et al.
Radiology 2005; 237:973-980
- "Multiple renal arteries were seen in 26% of kidneys. Early branching of the main renal artery was seen in 12% of kidneys."
Assessment of 100 Live Potential renal Donors for Lapatoscopic Nephrectomy with Multidetector Row Helical CT
Holden A et al.
Radiology 2005; 237:973-980
- "Excretory phase CT with oral hydration opacified the calyx/infundibulum completely in 57% and nearly completely in 38%, opacified the renal pelvis completely in 94.5% and nearly completely in 3.5%, and opacified the upper ureter completely in 78% and completely in 78% and nearly completely in 6.5%."
- "Excretory phase CT with oral hydration opacified the calyx/infundibulum completely in 57% and nearly completely in 38%, opacified the renal pelvis completely in 94.5% and nearly completely in 3.5%."
Opacification of the Collecting System and Ureters on Excretory-Phase CT Using Oral Water as Contrast Medium
Kawamoto S, Horton KM, Fishman EK
AJR 2006; 186:136-140.
- "The addition of a saline bolus offers no improvement, whereas the addition of enhanced CT digital radiography offers significant improvement in collecting system opacification during CT urography."
Opacification of the Genitourinary Collecting System During MDCT Urography with Enhanced CT Digital Radiography: Nonsaline versus Saline Bolus
Sudakoff GS et al.
AJR 2006:186:122-129.
- Transitional Cell Carcinoma: Facts
- Clinical presentation usually hematuria
- Account for up to 10% or neoplasms of the kidney
- Often multifocal
- Age range is 60-70’s
- Risk Factors for Contrast Induced Nephrotoxicity
- Diabetes
- Preexisting renal insufficiency
- Dehydration
- Cardiovascular disease
- Advanced age
- Hypertension
- Hyperuricemia
- Risk Factors for Contrast Induced Nephrotoxicity
- Multiple myeloma
- Certain drug therapies especially chemotherapeutic drugs and long term use of nonsteroidal anti-inflammatory drugs
- "High risk patients may have less likelihood of developing contrast induced nephrotoxicity when iodixanol (Visipaque) is used rather than the low osmolar, nonionic contrast medium iohexol."
Nephrotoxic Effects in High Risk Patients Undergoing Angiography
Aspelin R et al.
N Engl J Med 2003;348:491-499
- "When protocols involving multiple scans are designed, an effort should be made to obtain as much diagnostic information as necessary with a sufficient but not unnecessary amount of radiation whenever possible."
Patient Radiation Dose at CT Urography and Conventional Urography
Nawfel RD et al.
Radiology 2004; 232:126-132
- "Measurements made from curved planar images are typically inaccurate because of the geometric distortion that occurs at increasing distances from the centerline."
Value of Curved Planar Reformations in MDCT of Abdominal Pathology
Desser TS et al.
AJR 2004;182:1477-1484
- "Bladder cancer tends to show peak enhancement with the 60-second scanning delay. Multidetector row helical CT is useful in the detection and staging of bladder cancer."
Bladder Cancer: Analysis of Multidetector Row Helical CT Enhancement Pattern and Accuracy in Tumor Detection and Perivesical Staging
Kim et al.
Radiology 2004; 231:725-731
- "Sensitivity and specificity in the diagnosis of perivesical invasion were 89% and 95% respectively, in 67 patients and increased to 92% and 98% respectively, in 44 patients with a time interval of 7 or more days between TURP and CT."
Bladder Cancer: Analysis of Multidetector Row Helical CT Enhancement Pattern and Accuracy in Tumor Detection and Perivesical Staging
Kim et al.
Radiology 2004; 231:725-731
- "The cancer detection rate and positive predictive value for cancer detection was 97% and 95% respectively, in 67 patients and increased to 100% and 100% in 44 patients with a time interval of 7 or more days between TURP and CT."
Bladder Cancer: Analysis of Multidetector Row Helical CT Enhancement Pattern and Accuracy in Tumor Detection and Perivesical Staging
Kim et al.
Radiology 2004; 231:725-731
- Bladder Cancer Enhancement
| Attenuation Value | 40 second scanning delay | 60 second scanning delay | 100 second scanning delay | | Mean plus standard deviation | 75 ± 14 | 106 ± 14 | 84 ± 14 | | range | 55-107 | 78-129 | 55-119 |
Radiology 2004; 231:725-731
- "Multidetector row CT can help assess well the renal vasculature and the urinary tract of living renal donors."
Living Donor Kidneys: Usefulness of Multi-Detector Row CT for Comprehensive Evaluation
Kim JK et al.
Radiology 2003; 229:869-876
- "Detection rate of CT angiography was 98% for arteries and 98% for veins."
Living Donor Kidneys: Usefulness of Multi-Detector Row CT (4 row) for Comprehensive Evaluation
Kim JK et al.
Radiology 2003; 229:869-876
- "MDCT angiography is highly accurate for detecting vascular anomalies and providing anatomic information for laparoscopic living donor nephrectomy."
Multidetector CT angiography for preoperative evaluation of living laparoscopic kidney donors.
Kawamoto S, Montgomery RA, Lawler LP, Horton KM, Fishman EK AJR 2003 Jun;180(6):1633-8.
- "Our study found a 9.9% prevalence of ovarian varices in the general population. Our findings suggest that half (57%)the patients with ovarian varices have pelvic congestion syndrome and that most (77%) of them benefit from ovarian vein embolization or ligation."
Ovarian Varices in Healthy Female Kidney Donors: Incidence , Morbidity and Clinical Outcome
Belenky A et al.
AJR 2002; 179:625-627
- Renal Cell Carcinoma: Facts
- 85% of all renal cancers in adults
- 30,000 new cases diagnosed in the US each year
- M>F by 2-1
- Peak incidence is age 50-70
- Tumors are adenocarcinomas
- Renal Cell Carcinoma: Risk Factors
- Acquired cystic renal disease
- Chronic renal failure
- Von Hippel Lindau disease
- Smoking
- Hereditary renal cell carcinoma
- "The prevalence of a hemodynamically significant stenosis isolated to an accessory renal artery was 1.5% in our study. Thus, failure to detect accessory renal arteries should not unduly affect the utility of a non-invasive test for detecting renovascular hypertension."
Is It Necessary to Study Accessory Arteries When Screening the Renal Arteries for Renovascular Hypertension
Bude RO et al.
Radiology 2003;226:411-416
- "There is no statistically significant difference between 3D MR angiography and multidetector row CT angiography in the detection of hemodynamically significant arerial stenosis of the aortoiliac and renal arteries."
Aortoiliac and Renal Arteries: Prospective
Intraindividual Comparison of Contrast Enhanced three Dimensional MR Angiography and Multidetector Row CT Angiography
Willmann JK et al.
Radiology 2003;226:798-811
- "Patient acceptance was best for CT angiography."
Aortoiliac and Renal Arteries: Prospective
Intraindividual Comparison of Contrast Enhanced three Dimensional MR Angiography and Multidetector Row CT Angiography
Willmann JK et al.
Radiology 2003;226:798-811
- CT Urography: Protocol
- Unenhanced CT from kidneys to bladder
- Nephrographic phase from diaphragm to iliac crests with 110 sec delay
- Excretory phase at 8 minutes from kidneys thru bladder
- Multidetector Row CT Urography in the Evaluation of Hematuria
Joffe SA et al
RadioGraphics 2003;23:1441-1456
- Papillary Necrosis: Etiologies
- Diabetes
- Analgesic abuse
- Sickle cell disease
- Renal vein thrombosis
- Obstructive uropathy
- "Multidetector row CT can help assess well the renal vasculature and the urinary tract of living renal donors."
Living Donor Kidneys: Usefulness of Multi-Detector Row CT for Comprehensive Evaluation
Kim JK et al.
Radiology 2003; 229:869-876
- "Detection rate of CT angiography was 98% for arteries and 98% for veins."
Living Donor Kidneys: Usefulness of Multi-Detector Row CT (4 row) for Comprehensive Evaluation
Kim JK et al.
Radiology 2003; 229:869-876
- "At our institution, CT urography virtually replaced conventional urography in the evaluation of patients with hematuria and has proven successful in depicting a wide range of diseases affecting the urinary tract."
Multidetector CT Urography with Abdominal Compression and Three Dimensional Reconstruction
Chow LC et al.
AJR 2001;177:849-855
- "CT Angiography produced interpretable multiplanar images of the renal artery, even with a a metallic stent in place, and was adequate for determining stent patency. Compared with catheter angiography, the intrastent luminal diameter was underestimated in most patients who underwent CT Angiography."
Thin-Section Multidetector CT Angiography of Renal Artery Stents
Behar JV et al.
AJR 2002;178:1155-1159
- "The diameter of the renal artery stent lumen measured on catheter angiography (mean, 5.9 +/- 1.3 mm) was greater than that on CT angiography (mean stent lumen diameter for direct axial plane was 4.6 +/- 1.0 mm)."
Thin-Section Multidetector CT Angiography of Renal Artery Stents
Behar JV et al.
AJR 2002;178:1155-1159
- von Hippel-Lindau Disease: Facts
- Autosomal dominant familial tumor syndrome
- High penetrance with variable expression
- Prevalence of one in 50,000
- Defect in short arm of chromosome 3
- von Hippel-Lindau Disease: organ involvement
- Kidney
- Adrenal
- Pancreas
- Brain
- Spinal cord
- Retina
- von Hippel-Lindau Disease: Renal Pathology
- Renal cysts- occur in 50-75% of patients and are usually multiple and bilateral
- Renal cell carcinoma-occur in 28-45% of patients and occur at a younger age (30-36 yrs). The lesions are often multiple and bilateral and may be hypovascular or cystic lesions with mural nodules
- von Hippel-Lindau Disease: Adrenal Pathology
- Pheochromocytoma
- Occur in up to 30% of families with VHL
- They are bilateral in up to 50% of patients with a malignancy rate of around 10%
- Up to 18% are extraadrenal in location
- von Hippel-Lindau Disease: Pancreatic Pathology
- Occur in up to 77% of patients
- Lesions include
- Simple pancreatic cysts
- Serous cystadenomas
- Neuroendocrine tumors
- Pancreatic carcinoma
- von Hippel-Lindau Disease: Uncommon Pathology
- Liver cysts
- Cystadenomas of the epididymis and broad ligament
- "In evaluating Robson stage I of renal cell carcinoma, we were able to diagnose fat infiltration on 1-mm scans with 96% sensitivity, 93% specificity, and 95% accuracy; the positive and negative predictive values were, respectively, 100% and 93%."
High-Resolution Multidetector CT in the Preoperative Evaluation of Patients with Renal Cell Carcinoma
Catalano C et al.
AJR 2003; 180:1271-1277
- "On portal venous phase contrast enhanced CT scans, attenuation greater than 70HU or moderate or marked internal heterogeneity favor a diagnosis of renal cell carcinoma oer a diagnosis of high attenuation renal cyst."
Distinction of Renal Cell carcinomas from High Attenuation Renal Cysts at Portal Venous Phase Contrast Enhanced CT
Suh M et al
Radiology 2003; 228:330-334
- Sickle Cell Disease:Organ Involement
- Bone
- Brain
- Lungs
- Liver
- Spleen
- Kidney
- Sickle Cell Disease: Subgroups
- SS disease (homozygous Hb SS)
- SC disease
- S-thal
- Sickle Cell trait is associated with a rare renal tumor- medullary carcinoma.
- Sickle Cell Disease: Renal Involvement
- Glomerulosclerosis leading to
- Proteinuria
- Nephrotic syndrome
- Renal failure
- "The attenuation coefficient of a cystic renal lesion increased by no more than 10H among the unenhanced, corticomedullary, and parenchymal phase scans."
Analysis of Changes in Attenuation of Proven Renal Cysts on Different Scanning Phases of Triphasic MDCT
Chung EP et al.
AJR 2004; 182:405-410
- "This study shows that cystic lesions typically reveal a change in attenuation of less than 10HU between the scanning phases of a triphasic MDCT, affirming Bosniaks initial assertion that 10HU is a reasonable cutoff for determining enhancement in renal lesions."
- "This study shows that cystic lesions typically reveal a change in attenuation of less than 10HU between the scanning phases of a triphasic MDCT, affirming Bosniaks initial assertion that 10HU is a reasonable cutoff for determining enhancement in renal lesions."
Analysis of Changes in Attenuation of Proven Renal Cysts on Different Scanning Phases of Triphasic MDCT
Chung EP et al.
AJR 2004; 182:405-410
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