Mario Pagés

Evaluation of hepatocellular carcinoma using SonoVue, a second generation ultrasound contrast agent: correlation with cellular differentiation

The appearance of hepatocellular carcinoma (HCC) with contrast-enhanced ultrasound (CEUS) in the vascular phase is described and evaluated as to whether the enhancement pattern correlates with the degree of cellular differentiation. One hundred four HCCs were prospectively evaluated with CEUS using coherent-contrast imaging (CCI) and SonoVue with a low mechanical index (<0.2). The enhancement of HCCs in the vascular phase was analyzed according to the degree of pathological differentiation obtained by fine-needle biopsy. In the arterial phase, all HCCs except for four well differentiated ones (96.2%) showed enhancement (P<0.05). Histological differentiation of hypoechoic lesions in the early portal phase (7 HCCs; 16%) significantly differed from hyperechoic (1 HCC; 1%) or isoechoic lesions (87 HCCs; 83.6%) (P<0.05), with a significant probability of a worse differentiation in hypoechoic lesions. Histological differentiation of isoechoic lesions in the late phase (30 HCCs; 28.8%) significantly differed from hypoechoic lesions (74 HCCs; 71.2%) (P<0.05), with a significant probability of a better differentiation in isoechoic lesions. CEUS using CCI and SonoVue revealed enhancement in the arterial phase in >95% of HCCs, with a few well-differentiated cases not being diagnosed due to the absence of enhancement. Echogenicity in the portal and late phases correlated with cellular differentiation.

Characterization of focal liver lesions: comparative study of contrast-enhanced ultrasound versus spiral computed tomography

The purpose of this study was to compare the diagnostic accuracy of contrast-enhanced ultrasound (CEUS) with spiral computed tomography (SCT) for the characterization of focal liver lesions (FLL) and to determine the degree of correlation between the two techniques. Seventy-seven FLL (45 hepatocellular carcinomas; 12 metastases; ten hemangiomas; two regenerating/dysplastic nodules; eight focal nodular hyperplasias) detected with ultrasound (US) were prospectively evaluated by CEUS using a second-generation contrast agent and SCT (with an interval of no more than one month between the two techniques). Independent observers made the most probable diagnosis and the results were compared with the final diagnoses (histology n = 59; MRI n = 18). Statistical analysis was performed by the Chi-square and Kappa tests. CEUS provided a correct, specific diagnosis in 69/77 (90%) of the FLL, while SCT did so in 67/77 (87%). The sensitivity, specificity, and diagnostic accuracy for malignancy were 91%, 90%, and 91%, respectively, for CEUS and 88%, 89%, and 88%, respectively, for SCT. No statistically significant difference was found between CEUS and SCT in the characterization of FLL (p > 0.05). In addition, agreement between the two imaging techniques was good (k = 0.75). We conclude that CEUS and SCT provide a similar diagnostic accuracy in the characterization of FLL, with a good degree of correlation between the two techniques.

EUS and magnetic resonance imaging in the staging of rectal cancer: a prospective and comparative study

BACKGROUND Accurate locoregional staging is crucial in rectal cancer for deciding patient management because the administration of neoadjuvant therapy depends on it. EUS and magnetic resonance imaging (MRI) are used indistinctly in the pretherapeutic workup of rectal cancer. OBJECTIVE To prospectively compare the performance of EUS and MRI in the locoregional staging of rectal cancer in a large series of patients. DESIGN Prospective and comparative study. SETTING Tertiary center. PATIENTS Patients with histologically proven rectal cancer. INTERVENTIONS EUS and MRI were performed in all patients by a different operator unaware of the results of the other procedure. MAIN OUTCOME MEASUREMENTS Epidemiological, clinical, radiological, and echographic variables were evaluated. Pathological examination of the surgical specimen was used as the criterion standard. RESULTS Ninety patients (54 men and 36 women with a mean age of 68 ± 12 years; range 33-87 years) constitute the final sample of this study. Most of the tumors were stages T2-T3 (85%; 95% CI, 77%-92%). Twenty of them (22%; 95% CI, 14%-32%) were stenotic and 24 (27%; 95% CI, 18%-37%) had polypoid morphology. The accuracy of T staging was very similar for EUS and MRI for stage T2 (76%; 95% CI, 65%-84% and 77%; 95% CI, 67%-85%, respectively; P = not significant) and stage T3 (76%; 95% CI, 65%-84% and 83%, 95% CI, 73%-90%, respectively; P = not significant). MRI was not able to visualize any T1 tumor, whereas EUS understaged all T4 tumors. The univariate analysis showed that the polypoid morphology of the tumor inversely correlated with T staging on MRI. The accuracy of MRI for N staging was higher than that of EUS, although the difference did not reach statistical significance (79%; 95% CI, 65%-88% and 65%; 95% CI, 51%-78%, respectively). When performing the univariate analysis to assess the reasons for this difference, the presence of a stenotic tumor was the only parameter significantly related to a poorer performance of EUS in N staging. LIMITATIONS The small number of early and locally advanced lesions. CONCLUSIONS EUS and MRI have similar accuracy in the T and N staging in rectal cancer. The presence of stenosis and polypoid morphology is inversely associated with accuracy for either EUS or MRI.

MRA is useful as a follow-up technique after endovascular repair of aortic aneurysms with nitinol endoprostheses

To evaluate whether MR angiography (MRA) is a useful tool for the follow‐up of aortic aneurysms treated with nitinol endoluminal grafts.

Comparison of Endoscopic Ultrasonography and Magnetic Resonance Cholangiopancreatography in the Diagnosis of Pancreatobiliary Diseases: A Prospective Study

OBJECTIVES:To compare the diagnostic value of endoscopic ultrasonography (EUS) and magnetic resonance cholangiopancreatography (MRCP) in: (a) patients with a dilated biliary tree unexplained by ultrasonography (US) (group 1), and (b) the diagnosis of choledocholithiasis in patients with nondilated biliary tree (group 2).METHODS:Patients were prospectively evaluated with EUS and MRCP. The gold standard used was surgery or EUS-FNA and ERCP, intraoperative cholangiography, or follow-up when EUS and/or MRCP disclosed or precluded malignancy, respectively. Likelihood ratios (LR) and pretest and post-test probabilities for the diagnosis of malignancy and choledocholithiasis were calculated.RESULTS:A total of 159 patients met one of the inclusion criteria but 24 of them were excluded for different reasons. Thus, 135 patients constitute the study population. The most frequent diagnosis was choledocholithiasis (49% in group 1 and 42% in group 2, P = 0.380) and malignancy was more frequent in group 1 (35% vs 7%, respectively, P < 0.001). When EUS and MRCP diagnosed malignancy, its prevalence in our series (35%) increased up to 98% and 96%, respectively, whereas it decreased to 0% and 2.6% when EUS and MRCP precluded this diagnosis. In patients in group 2, when EUS and MRCP made a positive diagnosis of choledocholithiasis, its prevalence (42%) increased up to 78% and 92%, respectively, whereas it decreased to 6% and 9% when any pathologic finding was ruled out.CONCLUSIONS:EUS and MRCP are extremely useful in diagnosing or excluding malignancy and choledocholithiasis in patients with dilated and nondilated biliary tree. Therefore, they are critical in the approach to the management of these patients.

Preoperative evaluation of biliary anatomy in adult live liver donors with volumetric mangafodipir trisodium enhanced magnetic resonance cholangiography

Accurate preoperative depiction of biliary anatomy is not always adequately accomplished by imaging techniques in living donor liver transplantation (LDLT). We present the results of a prospective study designed to evaluate the ability of mangafodipir trisodium (Mn‐DPDP)‐enhanced magnetic resonance (MR) cholangiography (MRC) for this purpose in a series of 25 adult living liver donors (LLDs). We also analyze if a simple or a more complex surgical procedure can be preoperatively suggested for biliary reconstruction in the recipients. Findings on MRC were compared with operative cholangiography (OC). A conventional distribution with a right hepatic duct (RHD) longer than 1 cm anticipated a simple procedure (duct‐to‐duct anastomosis or hepaticojejunostomy [HJ]). A shorter RHD or any variant were predictors of a more complex surgery (bench ductoplasty or multiple anastomoses). Agreement between MRC and OC in assessing the biliary anatomy was measured using the κ statistic, and differences between the kind of surgery predicted at MRC and the biliary anastomosis performed were evaluated with Fishers exact test. Normal variants were present in 16 / 25 donors (64%). MRC was accurate in depicting the pattern of bile duct distribution observed at OC in 22 / 25 (88%) donors (κ = .831), and correctly predicted the complexity of biliary anastomosis in the recipient in 22 / 25 (88%) donors. No significant differences were observed between complexity of biliary surgery proposed at MRC and the final surgery performed (P = .002). In conclusion, Mn‐DPDP‐enhanced MRC is highly accurate in depicting the biliary duct anatomy and can be used preoperatively for surgical planning in LDLT. (Liver Transpl 2004;10:1391–1397.)

Role of 3.0-T MR Colonography in the Evaluation of Inflammatory Bowel Disease

Conventional colonoscopy combined with histologic analysis represents the standard of reference for the evaluation of colorectal disease and is usually the initial examination in patients with a suspected or established diagnosis of inflammatory bowel disease (IBD). However, it is increasingly being recognized that colonoscopy is limited to providing information regarding mucosal alterations. Colonoscopy cannot help estimate the depth of involvement of colonic lesions and does not provide information regarding the presence of extraluminal complications such as abscesses or fistulas. Recent technologic advances in magnetic resonance (MR) imaging, with its high spatial and tissue resolution, have raised expectations as to the potential role of this modality in the evaluation of colonic lesions in patients with IBD, as either a complement or an alternative to colonoscopy. MR colonography allows the characterization of colonic changes in acute and chronic IBD and can depict a wide spectrum of related lesions, including ulcers, edema, wall thickening, hyperemia, and fistulas, as well as potential extraluminal complications. The bulk of available evidence indicates that MR colonography can be useful as a problem-solving tool in the evaluation of IBD, as an alternative to colonoscopy whenever tissue sampling is not required, and for the assessment of the entire colon in cases of incomplete colonoscopy.

Imaging bile duct tumors: staging

Cholangiocarcinoma (CC) is the most frequent neoplasm of the biliary system. According to its anatomic origin in the biliary tree it is usually classified as intrahepatic, perihilar, or extrahepatic distal CC. Tumors originated in these areas differ in biological behavior and management. The stratification of the patients aligned to therapeutic options and prognosis is a key point in the management of CC. Thus, specific staging systems have been designed for each anatomical location. They are precise for surgical planning, to establish prognosis after surgery, or to compare the benefits of different therapeutic approaches, but they are less accurate to stratify patients into a therapeutic decision algorithm. Imaging tools, mainly multidetector computed tomography and magnetic resonance imaging (MRI), allow full assessment of the diagnosis and extension of the tumor. They are especially useful in establishing the correct diagnosis and determining resectability, which reaches a high negative predictive value, identifying those patients in whom surgery will not be effective. We will discuss the different staging systems for CC, the radiologic characteristics with classical and recently described signs that allow a confident diagnosis of the disease and the criteria for resectability of biliary tract malignancies.

Uncommon Tumors and Pseudotumoral Lesions of the Pancreas

Ductal adenocarcinoma is the most common tumor of the pancreas, accounting for about 80% of all pancreatic tumors. The other 20% of pancreatic tumors is represented by a heterogeneous group of pancreatic neoplasms that includes cystic pancreatic neoplasms, islet cell tumors, and the so-called rare pancreatic tumors. In addition, the pancreatic gland may present a variety of inflammatory and pseudotumoral lesions that may mimic a primary pancreatic neoplasm. These uncommon tumors and pseudotumoral lesions present a wide spectrum of imaging findings and they are often poorly understood by the radiologist, becoming a diagnostic challenge. Some of these lesions may show an appearance similar to ductal adenocarcinoma being radiologically indistinguishable. However, some of these lesions sometimes may present specific features on imaging studies that may help to characterize the mass and to suggest a correct diagnosis. Many of these uncommon tumors and pseudotumoral lesions have a different approach, therapy, and prognosis than ductal adenocarcinoma. Therefore, it is important for the radiologist to be familiar with these entities to include them in the differential diagnosis to initiate an appropriate lesion-specific workup and treatment. In the present article, we review the radiological features of uncommon pancreatic tumors, atypical manifestations of ductal adenocarcinoma, and pseudotumoral masses, focusing on those features that can be helpful for the differential diagnosis.

Leiomyomatosis peritonealis disseminata (2006: 9b)

A 35-year-old woman with regular periods and no history of pregnancy or use of oral contraceptive presented with a 3-week history of abdominal pain and a hypogastric mass. Previous medical history is uneventful other than a previous laparoscopic myomectomy for isolated uterine leiomyoma 3 years previously. There was no asthenia or anorexia. Physical examination revealed two firm hypogastric masses of approximately 4-cm diameter. On gynaecological examination the uterus was prominent and there was a nonfixed tender mass in the right adnexa. She underwent transabdominal ultrasonography (US), which showed the presence of multiple hypoechoic small nodules in the pelvis, abdomen and subhepatic space with moderate ascites (Fig. 1a,b). During transvaginal ultrasonography, many abdominal nodules (30–70 mm) were identified, with a normal uterus and right ovary and moderate ascites. The left ovary could not be demonstrated. CT demonstrated a multinodular well-demarcated mass arising from the pelvis extending to the right side of the abdomen and subhepatic space. Portal phase imaging revealed multiple nodules that show heterogeneous enhancement with central hypodense areas. Subtle enhancement was identified in the right parietal peritoneum with ascites. No abnormal retroperitoneal lymph nodes were identified Magnetic resonance (MR) imaging was performed to gain further information; this also demonstrated a multilobular mass on T1and T2weighted images, which enhanced after administration of intravenous gadolinium DTPA (Figs. 3a,b, 4) (Fig. 2a,b). Diagnostic laparoscopy was performed. Multiple vascularized nodules resembling leiomyomata were seen along the abdominal cavity with ascites. A biopsy of one of the nodules was performed. Histological examination indicated leiomyomatosis peritonealis disseminata (LPD) without any evidence of malignancy. The oestrogen receptors were negative and progesterone receptors were positive. During subsequent laparotomy for conservative treatment, more than 20 nodules varying in size from 5 to 10 cm were removed from the surface of the uterus, large intestine, right broad ligament, posterior parietal peritoneum and parietal peritoneum of the right side of the abdomen (Fig. 5a,b). Histological examination of the nodules confirmed benign LPD.