Preoperative right portal vein embolization in patients with metastatic liver disease. Metastatic liver volumes after RPVE.

PURPOSE: To quantify liver metastases and future remnant liver (FRL) volumes in patients who underwent right portal vein embolization (RPVE) and to evaluate the effects of this procedure on metastase growth. MATERIAL AND METHODS: Nine patients with liver metastases from primary colon (n = 5), rectal lesions (n = 1) and carcinoid tumors (n = 3) underwent spiral CT to evaluate the ratio of the non-tumorous parenchymal volume of the resected liver to that of the whole liver volume (R2). Hand tracing was used to isolate the entire liver, the resected liver and metastase volumes. All patients with R2 > 60% underwent RPVE. RESULTS: FRL exhibited a 101-336 cm3 (average 241 cm3) increase in volume 1 month after RPVE. One patient refused surgery for 2 months and before surgery the increase in volume of the FRL was similar to that of other patients (180.64 cm3). Percent metastases volume from colorectal carcinoma in embolized liver parenchyma increased from 62.4% to 138.4% at 1 month and to 562% at 2 months after RPVE. Metastase volume from carcinoid tumors was unchanged. CONCLUSION: One month after RPVE, hypertrophy of the FRL is evident. In the embolized liver, there was a progressive increase in metastase volume from colorectal carcinoma while metastase volume from carcinoid tumor was unchanged in embolized and non-embolized liver.

Thymic lesions and myasthenia gravis. Diagnosis based on mediastinal imaging and pathological findings.

PURPOSE: To achieve a better understanding of the role of CT and MR imaging in the study of the mediastinum in patients with myasthenia gravis (MG). MATERIAL AND METHODS: Mediastinal CT and MR findings were correlated with the histopathological results in 104 thymectomized MG patients. RESULTS: CT was performed in 104 patients; in 11 of them, MR was also carried out. 44 patients had hyperplasia at histology. On CT, thymic hyperplasia was confirmed in 16 cases, thymoma was diagnosed in 10 and a normal thymus in 18 (sensitivity 36%, specificity 95%). Of 52 patients with thymoma at histology, CT showed thymoma in 46, hyperplasia in 1, and normal thymus in 5. CT showed 88.5% sensitivity and 77% specificity for thymoma. In 10 patients with invasive thymoma, CT was indiscriminate, while invasiveness was detected in 7 cases at MR (70% sensitivity) and at CT in 1 case. Both CT and MR detected tumor recurrence in 5 cases, but the exact localization and degree of invasion were best defined by MR. CONCLUSION: In MG patients CT is a sensitive, specific and efficient modality for detecting thymoma, but is less so for detecting thymic hyperplasia. MR was shown to be accurate in detecting invasive thymoma both preoperatively and in postoperative follow-up.

Magnetic resonance imaging in breast cancer recurrence.

PURPOSE: To determine the sensitivity, specificity and accuracy of magnetic resonance imaging (MRI) in detecting breast cancer recurrence. MATERIALS AND METHODS: Forty women conservatively treated for breast cancer underwent MRI and confirmation on histology and cytology of suspected local recurrence. In these patients both clinical and mammographic/ultrasound features of local recurrence were nonspecific or suspicious. All patients were examined at least 1 year after completion of radiation treatment. Dynamic magnetic resonance imaging was performed with a 1.5 T unit using a dedicated bilateral breast coil. Qualitative and quantitative data were obtained. Statistical analysis was also performed with the Student T-test. RESULTS: Breast cancer recurrence was confirmed on histology in 22 patients. MRI identified all the 22 breast recurrent cancers. False-positive contrast enhancement was seen in only two patients. In four patients recurrence was classified as multifocal. In one patient the tumor was detected in the contralateral breast. MRI showed 95% accuracy, 100% sensitivity, 88.8% specificity with 5% false-positives and 100% negative predictive value. CONCLUSION: Dynamic MRI appears a valuable technique for differentiation of post-treatment changes from recurrent carcinoma and for guiding the histological confirmation. Its high negative predictive value may have an impact on follow-up of treated breast.

[Malignant biliary hilar stenosis: MR cholangiography compared with direct cholangiography]. / Stenosi maligne ilari delle vie biliari: correlazione tra la colangiografia con risonanza magnetica e le colangiografie dirette.

AIM: To assess the diagnostic value of three-dimensional (3D) magnetic resonance cholangiography (MRC) versus direct cholangiography such as endoscopic retrograde cholangiography (ERC) and percutaneous transhepatic cholangiography (PTC) in malignant biliary stenosis. MATERIAL AND METHODS: Twenty-nine patients (15 female and 14 male) (mean age 62 years) with malignant biliary strictures underwent MRC and ERC. Breath-hold 3D steady state free precession MR cholangiography was performed on a 1.5-T imager in the patients before ERC. In 25 patients findings at ERC/PTC were considered the standard of reference: 19 patients underwent ERC, 5 PCT and 1 both ERC and PTC due to unsuccessful papilla cannulation during the endoscopic examination. In the 4 remaining patients the surgical specimen was considered the standard of reference. In the 29 patients studied, histology performed during direct cholangiography and the examination of the surgical specimens demonstrated that the malignant hilar stenoses were caused by hilar cholangiocarcinoma (n=7), cholangiocarcinoma of the distal VBP (n=1), gallbladder cancers (n=6), endometrial metastasis (n=2), ovary metastasis (n=1), colon metastasis (n=1), breast metastasis (n=1). The correct identification of biliary stenosis and extension of the tumor (according to the Bismuth classification) by MR cholangiography and ERC were independently assessed by two readers blinded to each other's report. The results were compared. RESULTS: Identification of biliary stenosis and neoplastic extension were accurate in respectively 29/29 (100%) and 26/29 (89%) cases with MR cholangiography. The comparison of ERC/PTC and MRC images yielded the following results: Bismuth Type I (6 vs 6), Type II (5 vs 8), Type III (13 vs 10), Type IV (5 vs 5). Our results indicate that MR is less capable of identifying the extension of small lesions at the primary confluence of bile ducts than are ERC/PCT. DISCUSSION AND CONCLUSIONS: MR cholangiography is a non-invasive technique for biliary tract imaging. It does not require administration of contrast medium and allows complete visualisation of the biliary ducts. MR cholangiography allowed accurate diagnosis of malignant hilar stenosis providing equal information as direct cholangiography and may therefore obviate the need for ERC/PTC.

Destructive spondyloarthropathy of the cervical spine in long-term hemodialyzed patients: a five-year clinical radiological prospective study.

OBJECTIVE: To describe the radiographic features and progression of cervical spine destructive spondyloarthropathy (DSA) in hemodialyzed patients, and to evaluate the relationship between this disease and patient characteristics, biochemical values, and hemodialysis duration. DESIGN AND PATIENTS: Standard radiographs, and lateral flexion and extension views of the cervical spine, were performed annually for 5 years in 31 hemodialyzed patients who were divided into three groups at the commencement of the study: those showing (I) DSA, (II) vertebral rim erosions (VRE) without DSA, and (III) absence of DSA and VRE. Magnetic resonance (MR) imaging and computed tomography (CT) were performed in seven and two patients respectively. The imaging features were evaluated for the presence and progression of spondyloarthropathy and correlated with clinical and biochemical variables. Statistical analysis was performed using one-way analysis of variance. RESULTS: The duration of hemodialysis appeared to be the main predictive factor (P=0.0003) for DSA, which was found in six patients (19%). DSA was found to correlate with higher levels of beta2-microglobulin (P<0.00001), parathyroid hormone (P<0.05), and alkaline phosphatase (P<0.05). Clinical symptoms were minimal. In two patients, MR imaging revealed changes mimicking spondylodiscitis. In another patient, CT of the craniocervical junction showed bone resorption due to a pseudotumor, and basilar invagination. CONCLUSIONS: DSA of the cervical spine is often clinically silent. Pathogenesis of DSA may be multifactorial but its progression is most influenced by the duration of hemodialysis. On MR imaging, DSA may mimic spondylodiscitis.

MRI assessment of ventricular function.

Cine-MRI is a robust non invasive technique able to assess regional and global systolic function of both ventricles. Conventinal cine-MRI was used for LV global function parameters both on horizontal long axis and vertical long axis, applying area-length methods, as in echocardiography. Recent developments of segmented k-space techniques allowed breath-held cine-MRI, making possible a rapid acquisition of the entire ventricles, both left and right. Using the Simpson's rule volumes are estimated with high accuracy, without any geometrical assumption; this method is considered gold standard for global function assessment. Regional function is studied by cine-MRI both qualitatively and quantitatively, as it represents the best technique in defining endo- and epi-cardial borders. The ability of quantify wall thickness and wall thickening makes cine-MRI highly suitable for stress-imaging, both in ischemia detection and viability assessment. Tagging is a novel technique, able to assess the complex mechanism of myocardial contraction and to quantify myocardial strain. Finally MRI is also able to assess diastolic function with phase velocity mapping.

Contrast-enhanced gray-scale and color Doppler voiding urosonography versus voiding cystourethrography in the diagnosis and grading of vesicoureteral reflux.

PURPOSE: The purpose of this study was to compare contrast-enhanced gray-scale voiding urosonography (CE-VUS) and contrast-enhanced color Doppler voiding urosonography (CE-CDVUS) with voiding cystourethrography (VCUG) to verify whether the use of color Doppler imaging improves the diagnosis and grading of vesicoureteral reflux (VUR). METHODS: In 74 patients, CE-VUS and CE-CDVUS were compared with VCUG, which was used as the gold standard. SHU 508 A (Levovist) was used as the echo-enhancing contrast agent. VUR was diagnosed if hyperechoic dots or color signals were visualized in the ureter on sonograms. VUR grading was based on morphologic and dynamic findings on CE-VUS and morphologic and color findings on CE-CDVUS. VCUG was performed conventionally, and grading by VCUG was in accordance with the international system of radiographic VUR grading. Patients who voided during 1 examination only (either CE-VUS and CE-CDVUS or VCUG) were excluded from the study. Agreement between the results of CE-VUS and VCUG and between those of CE-CDVUS and VCUG in diagnosing VUR was calculated by kappa statistics. CE-VUS and CE-CDVUS were compared for diagnostic accuracy by the McNemar test. RESULTS: The agreement between CE-VUS and VCUG in predicting VUR was 90% (kappa score, 0.77; p < 0.001). The agreement between CE-CDVUS and VCUG was 96% (kappa score, 0.91; p < 0.001). CE-CDVUS showed a significantly higher diagnostic accuracy than did CE-VUS (96% versus 90% of cases correctly classified; McNemar chi2 = 4; p < 0.05). This was mainly related to the lower number of false-negative results for grade I and grade II VUR when CE-CDVUS was used. CONCLUSIONS: The use of color Doppler imaging significantly improves the accuracy of contrast voiding urosonography in the detection and grading of VUR.

Sonographic diagnosis of distal biceps tendon rupture: a prospective study of 25 cases.

OBJECTIVE: To describe the sonographic findings of distal biceps tendon ruptures and to assess the accuracy of the technique. METHODS: Twenty-five patients with clinically indicated distal biceps tendon ruptures were prospectively studied by sonography. Five patients also underwent magnetic resonance imaging. Surgical confirmation was obtained in 14 patients. RESULTS: Seventeen complete tendon ruptures and 3 partial tears were correctly shown by sonography; 1 complete rupture was incorrectly shown as a partial tear by sonography. Sonographic features of complete rupture were absence of tendon in the expected location, fluid collection in a typical tendon gap, and a mass in the antecubital fossa. Sonographic features of incomplete rupture were intratendinous hypoechogenicity and tendon thinning. Peritendinous fluid was found in complete and incomplete ruptures. CONCLUSIONS: In distal biceps tendon ruptures, sonography is a cost-effective method that can confirm the clinical indications with good accuracy and can show tendon lesions when the clinical indications are low.

Magnetic resonance pancreatography (MRP): morphology and function.

MRCP is able to non-invasively assess the pancreatic ducts, with moderate/high agreement with ERCP: There is however a high number of false negative results, mainly due to the small size of the main pancreatic duct, especially in the tail, and side branches. Secretin stimulates the exocrine pancreas with accumulation of fluid and bicarbonates in the ductal system, and subsequent enlargement. This increase in caliber improves the assessment of the morphology of pancreatic ducts and their abnormalities. MRCP accuracy in assessing ductal abnormalities, improves after secretin administration. Furthermore, dynamic MRCP during secretin administration is also able to afford the functional evaluation of the pancreatic flow dynamics. Papillary stenosis, either idiopathic or due to Santorinicele, is easily diagnosed by means of S-MRCP. Furthermore a noninvasive assessment of the pancreatic exocrine reserve can be performed with dynamic MRCP during secretin administration.

Imaging of chronic pancreatitis.

Chronic pancreatitis is characterized by progressive, irreversible morphologic changes whose most common cause is excessive alcohol intake. Radiologic imaging plays a major role in the diagnosis, staging of disease severity, detection of complications and selection of treatment options. The sensitivity of US ranges from 60% to 70% while its specificity is higher reaching 80%-90% in the detection of abnormalities of main pancreatic duct. As for CT, its sensitivity and specificity in the diagnosis of chronic pancreatitis, in recent studies is 74% and 85% respectively. The performance of Magnetic Resonance cholangiopancreatography was shown to be enhanced by secretin stimulation with better visualization of ductal and parenchymal changes. However, endoscopic retrograde cholangiopancreatography is the most sensitive indicator of the presence and extent of the disease. Ductal abnormalities can be used to classify chronic pancreatitis.

Imaging of acute pancreatitis.

Pancreatitis is one of the most complex and clinically challenging of all abdominal disorders. It is classified according to clinical, morphologic and histologic criteria. The primary role of radiologic imaging in patients with suspected pancreatitis is to confirm or exclude the clinical diagnosis of pancreatitis. Second, if possible, the cause of the disease is established with the assessment of disease severity and detection of complications. Imaging can also provide guidance for percutaneous therapy. Sonography in acute pancreatitis is a good screening test in patients with suspected biliary pancreatitis and a mild clinical course. Contrast-enhanced CT is preferred for patients with acute pancreatitis because it can accurately diagnose and stage the disease and the necessary information for percutaneous management is provided. The diagnosis of acute pancreatitis on MRI relies on the presence of morphologic and peripancreatic changes. Pancreatic necrosis and complications of acute pancreatitis such as hemorrhage, pseudocysts or abscesses are well-examined by MRI.

High resolution spiral computed tomography of the pancreas.

Computed tomography (CT) is a very useful tool in the assessment of pancreatic disease. Searching for subtle signs, as in chronic pancreatitis or staging of adenocarcinoma, high spatial and contrast resolution is needed. The high resolution computed tomography (HRCT) technique for pancreatic scans, and its evolution from dynamic CT to multislice spiral CT, is described. 2D and 3D dimensional reconstructions are depicted and their role in diagnosis is focused. Together with spatial resolution, contrast enhancement protocols are discussed, aimed to achieve optimal contrast between the lesion and normal parenchyma.

Staging of pancreatic ductal adenocarcinoma with spiral CT and MRI.

Detection of pancreatic adenocarcinoma is crucial for accurate staging both with spiral CT and dynamic MRI; consequently an accurate technique is required and so-called pancreatic phase is recognized as the best one for tumor conspicuity. For vascular involvement optimal results have been achieved in assessing unresectability; vein involvement seems more difficult to be defined as it is sustained by a different spread compared to arterial involvement. Grading of vessel circumference contact represents the best tool in "venous" staging, but shape deformation and collateral veins dilation are also important signs. Lymph node staging is less accurate, lacking in specificity, but spiral CT demonstrated better results if compared with dynamic MRI. Assessment of liver metastases has been improved by the advent of spiral CT and dynamic contrast enhanced MRI, while peritoneal staging seems to be unaffected. In conclusion, both spiral CT and dynamic contrast enhanced MRI are accurate in pancreatic adenocarcinoma staging, mainly for vessels and liver involvement; no definite differences have been established, because only a few studies have compared them both with state-of-art techniques. Therefore standardized multicentric trials are desirable. Up to now, the choice of which technique to employ should be based on local expertise; moreover, the aggressive approach of surgical equipes should be kept in mind.

[Role of Doppler color ultrasonography in the diagnosis of thyroid carcinoma]. / Ruolo dell'eco-color-doppler nella diagnosi dei carcinomi tiroidei.

The aim of this study is to assess the efficacy and accuracy of color flow-Doppler sonography (CFDS) in predicting the malignancy of thyroid nodules. Seventy eight consecutive patients (52 females and 26 males), with 78 thyroid nodules (29 single nodules and 49 in a nodular goiter) have been examined by CFDS, before surgery, evaluating the hypoechogenicity of the nodule, the presence of microcalcifications and the halo sign absent and the vascular pattern, which has been classified as follows: absence of blood flow (type I), perinodular blood flow (type II), intranodular, with or without perinodular blood flow (type III), which is considered the most typical pattern of malignancy. On histology 22 nodules as carcinoma (CA) and 56 as benign nodules (BN) have been diagnosed. The most predictive for malignancy, sonographic pattern, "microcalcifications", has been found in 13/22 CA and in 4/56 BN (P < 0.0001, specificity 93%, sensitivity 59%); "hypoechogenicity" in 16/22 CA and in 8/56 BN (P < 0.0001, specificity 86%, sensitivity 73%), "absent halo sign" in 18/22 CA and in 16/56 BN (P < 0.0001, specificity 71%, sensitivity 82%.) have been found. On CFD type III pattern has been detected in 17/22 CA and in 24/56 BN (P < 0.15, specificity 57%, sensitivity 77%); type IIIa pattern (intranodular without perinodular blood flow) has been the most predictive for malignancy (P < 0.0001, specificity 100%, sensitivity 36%). The combination of type III pattern with "hypoechogenicity" in 13/22 CA and in 2/56 BN (p < 0.0001, specificity 93%, sensitivity 59%) has been found, with "absent halo sign" in 15/22 CA and in 3/56 BN (P < 0.0001, specificity 94.6%, sensitivity 68%), has been found, with "microcalcification" in 10/22 CA and in 0/56 BN (P < 0.0001, specificity 100%, sensitivity 45%) has been found. The combination of "microcalcifications" and absent halo sign" with type III pattern has been the most specific for malignancy, being detected in 11/22 Ca and 2/56 BN (P < 0.0001, specificity 96%, sensitivity 50%). In conclusion our results suggest that CFDS has an useful role in the assessment of thyroid nodules and it may provide information highly predictive for malignancy, above all when multiple, sonographic and vascular patterns are contemporaneously present in a thyroid nodule.

Imaging of aortic atherosclerosis.

Aortic atherosclerosis correlates with future major cardiovascular events and the assessment of its degree and extent has important diagnostic value. Many imaging modalities can be used to assess atherosclerotic plaques. While Transesophageal Echocardiography (TEE) is the procedure of choice for the study of thoracic aortic atheromas, Magnetic Resonance Imaging (MRI) is a powerful diagnostic tool. MR study of aortic plaques requires T1, proton density and T2-weighed images. MR-angiography allows a comprehensive study of the aorta. Elementary plaque components of aortic atherosclerosis are identified with MRI and TEE; advanced lesions can be graded according to the America Heart Association criteria. MRI and TEE assessment of thoracic aortic atherosclerosis has demonstrated close agreement.

Role of color Doppler sonography in the assessment of musculoskeletal soft tissue masses.

Fifty-six patients with soft tissue masses of the limbs (36 benign, 20 malignant) prospectively underwent sonography (color Doppler and pulsed Doppler examinations) to assess the role of Doppler interrogation in differentiating benign from malignant lesions. Sonography showed 60% sensitivity, 55% specificity, 71% negative predictive value, 42% positive predictive value, and 57% accuracy. Color Doppler evaluation showed 85% sensitivity, 88% specificity, 91% negative predictive value, 80% positive predictive value, and 87% accuracy. Diastolic and venous velocities and pulsatility index values were not statistically significant. Mean systolic velocity was 0.27 m/s in benign lesions and 0.55 m/s in malignant lesions. By combining sonographic and Doppler data, a correct diagnosis was obtained in 51 of 56 patients (90% sensitivity, 91% specificity, 85% positive predictive value, 94% negative predictive value, 91% accuracy). Color Doppler and pulsed Doppler evaluations represent a useful adjunct to sonography and should be routinely included in the evaluation of musculoskeletal soft tissue masses by ultrasonography.