OBJECTIVE: To describe changes of the biliary tree demonstrated by magnetic resonance cholangiography (MRC) in patients with the hepatosplenic presentation of schistosomiasis mansoni, and evaluating the interobserver agreement in the detection of schistosomal cholangiopathy. MATERIALS AND METHODS: Prospective, cross-sectional study involving 24 patients with hepatosplenic schistosomiasis and 6 healthy patients (control group) submitted to biliary tree evaluation by MRC. The following changes of the biliary tree were considered: distortion, thinning, stenosis, dilation and irregularity. The interobserver agreement in the detection of biliary tree changes was calculated with the McNemar's test and the kappa index of agreement (κ). RESULTS: The interobserver agreement in the detection of distortion and thinning of the biliary tree was almost perfect (κ = 0.867; confidence interval [CI] 95% [0.512-1.0] and κ = 0.865; CI 95% [0.51-1.0], respectively). There was a substantial agreement for stenosis (κ = 0.78; CI 95% [0.424-1.0]), moderate agreement for dilation (κ = 0.595; CI 95% [0.247-0.942]) and mild agreement for thinning (κ = 0.229; CI 95% [0.095-0.552]). CONCLUSION: In a decreasing order of frequency, the changes of the biliary tree were observed: distortion, thinning, stenosis, dilation and irregularity. The interobserver agreement for signs of schistosomal cholangiopathy was almost perfect for distortion and thinning, and substantial for stenosis.

Keywords: Schistosomiasis mansoni, Magnetic resonance imaging, Cholangiography, Biliary ducts

OBJECTIVE: The present study was aimed at evaluating the accuracy of magnetic resonance cholangiography in the assessment of the biliary anatomy in living liver donors in correlation with surgical findings. MATERIALS AND METHODS: Fifty living liver donors were retrospectively evaluated at Hospital de Clínicas da Universidade Federal do Paraná, Curitiba, PR, Brazil. Cholangiographic images were analyzed and results were compared with intraoperative findings. Only anatomical alterations that affected the surgical strategy and had not been previously observed at magnetic resonance cholangiography were considered as being in disagreement. RESULTS: Anatomical variations were found in 7 donors at magnetic resonance cholangiography, and in 14 during surgery. Agreement between imaging and surgical findings was observed in 41 of the 50 patients, and disagreement in 9. Magnetic resonance cholangiography sensitivity, specificity, positive and negative predictive values, and accuracy were respectively 43%, 97%, 86%, 81% and 81.6%. CONCLUSION: Magnetic resonance imaging is a safe and noninvase method for preoperative evaluation of the biliary tract in living liver donors. However some anatomical abnormalities are not detected by magnetic resonance cholangiography.

Keywords: Liver transplant, Living donors, Magnetic resonance imaging, Biliary tract

We present a case of a 27-year-old male patient submitted to computed tomography and magnetic resonance imaging for the evaluation of a renal tumor. The radiological features of the mass suggested the diagnosis of a malignant renal tumor of parenchymatous origin. However, the histological findings proved to be a benign solitary fibrous tumor within the pelvis and caliceal portion of the right kidney.

Keywords: Neoplasia, Fibrous tumor, Kidney, Mesothelioma, Computed tomography, Magnetic resonance imaging

The melanotic neuroectodermal tumor of infancy, also known as progonoma, is a rare benign disease of neural crest origin that occurs within the first year of life and affects mainly the maxilla. The authors report a case of a 10-month-old child presenting with this uncommon tumor in the maxilla, emphasizing the diagnostic findings on computed tomography, and present a literature review.

Keywords: Neoplasia, Neural crest, Maxilla, Infancy, Computed tomography

The authors review the use of intraoperative ultrasonography (IOUS) in the management of biliary-pancreatic disease. The methodology of IOUS used for the examination of the biliary-pancreatic ductal system as well as the most important findings and pitfalls of image interpretation are described. Additionally, some ultrasonography findings in pancreatic tumors, pancreatitis, bile duct tumors and bile duct stones are presented. The authors emphasize the importance of understanding this ultrasonographic method due to the increasingly use of IOUS in biliary-pancreatic surgery.

Keywords: Intraoperative ultrasonography, Pancreas, Biliary ductal system

The authors describe the main applications of endoscopic ultrasonography for the management of diseases of the gallbladder and biliary ductal system. In addition, some ultrasound findings of benign and malignant diseases affecting these structures of the digestive tract are presented, emphasizing the diagnostic importance of endoscopic ultrasonography.

Keywords: Ultrasonography, Endoscopic ultrasonography, Digestive tract, Gallbladder, Biliary system

OBJECTIVE: The aim of this prospective study was to investigate the feasibility of using a negative oral contrast agent to null the bowel signal during magnetic resonance cholangiopancreatography. MATERIAL AND METHOD: Fifteen healthy volunteers with no previous history of pancreaticobiliary disease or surgery were imaged with a single-shot fast spin-echo pulse sequence, using a magnetic resonance imaging system operating at 1.0 T. Data acquisition was started before and after administration of oral contrast agent. Using the magnetic resonance images obtained before and after administration of oral contrast agent, the common bile duct, pancreatic duct and papilla were assessed and graded by two radiologists. The frequency of adverse effects and the tolerance of the contrast were also evaluated. RESULTS: All patients that found negative oral contrast agent unpleasant (73% of the cases) tolerated well the oral contrast agent. Adverse effects as abdominal pain and diarrhea were noted in 30% of the patients. In all patients the high signal intensity from the intestinal fluid was completely suppressed. The depictions of the common hepatic duct were slightly improved, whereas the depictions of the choledochus, papilla and pancreatic duct were markedly improved by the negative oral contrast agent administration. CONCLUSION: Negative oral magnetic resonance contrast agent can be an effective and safe contrast media in eliminating signal intensity of the gastrointestinal tract, thus improving the depiction of the biliary system in magnetic resonance cholangiopancreatography.

Keywords: Magnetic resonance imaging, Biliary system, Pancreatic duct, Contrast media

In the investigation of tumors with conventional magnetic resonance imaging, both quantitative characteristics, such as size, edema, necrosis, and presence of metastases, and qualitative characteristics, such as contrast enhancement degree, are taken into consideration. However, changes in cell metabolism and tissue physiology which precede morphological changes cannot be detected by the conventional technique. The development of new magnetic resonance imaging techniques has enabled the functional assessment of the structures in order to obtain information on the different physiological processes of the tumor microenvironment, such as oxygenation levels, cellularity and vascularity. The detailed morphological study in association with the new functional imaging techniques allows for an appropriate approach to cancer patients, including the phases of diagnosis, staging, response evaluation and follow-up, with a positive impact on their quality of life and survival rate.

Keywords: Cancer imaging; Magnetic resonance imaging; Oncology; Neoplasia; Functional imaging; Diffusion.

OBJECTIVE: The present study was aimed at evaluating the contribution of transrectal prostate ultrasound in the screening for prostate neoplasias and in the guidance of prostate biopsies. MATERIALS AND METHODS: Prospective study developed over a one-year period. All the patients with indication for prostate biopsy were evaluated. Regardless of PSA values, the patients underwent ultrasound in order to identify suspicious nodules (confirmed by two observers). Sextant biopsy was subsequently performed. In cases of finding suspicious nodules, an additional puncture directed to such nodules was done. RESULTS: In a total of 155 cases the prevalence of malignancy was of 53%. Suspicious nodules were detected in 34 patients, and 25 where malignant (positive predictive value of 74%). The specificity and sensitivity for suspicious nodules were 88% and 31% respectively. Comparatively with the randomly obtained sextant specimens, the rate of findings of neoplasia was higher in the specimens obtained with puncture directed to the nodule (p = 0.032). No statistically significant difference was observed in the Gleason score for both types of specimens (p = 0.172). CONCLUSION: The high positive predictive value and the high rate of findings of neoplasia in specimens of suspicious nodules should be taken into consideration in the future. The authors suggest a biopsy technique similar to the one described in the present study (sextant biopsy plus puncture directed to the suspicious nodule).

Keywords: Prostatic neoplasia; Ultrasonography; Imaging-guided biopsy; Diagnostic techniques and procedures; Screening.

OBJECTIVE: To determine the rates of diagnostic underestimation at stereotactic percutaneous core needle biopsies (CNB) and vacuum-assisted biopsies (VABB) of nonpalpable breast lesions, with histopathological results of atypical ductal hyperplasia (ADH) or ductal carcinoma in situ (DCIS) subsequently submitted to surgical excision. As a secondary objective, the frequency of ADH and DCIS was determined for the cases submitted to biopsy. MATERIALS AND METHODS: Retrospective review of 40 cases with diagnosis of ADH or DCIS on the basis of biopsies performed between February 2011 and July 2013, subsequently submitted to surgery, whose histopathological reports were available in the internal information system. Biopsy results were compared with those observed at surgery and the underestimation rate was calculated by means of specific mathematical equations. RESULTS: The underestimation rate at CNB was 50% for ADH and 28.57% for DCIS, and at VABB it was 25% for ADH and 14.28% for DCIS. ADH represented 10.25% of all cases undergoing biopsy, whereas DCIS accounted for 23.91%. CONCLUSION: The diagnostic underestimation rate at CNB is two times the rate at VABB. Certainty that the target has been achieved is not the sole determining factor for a reliable diagnosis. Removal of more than 50% of the target lesion should further reduce the risk of underestimation.

Keywords: Breast neoplasia; Core needle biopsy; Vacuum-assisted biopsy; Diagnostic techniques and procedures; Noninvasive intraductal carcinoma.

OBJECTIVE: This study aimed to compare two self-expanding stents, a nitinol stent and an elgiloy stent, both placed percutaneously, in terms of their efficacy in palliating inoperable malignant biliary obstruction. MATERIALS AND METHODS: We retrospectively investigated 99 patients with unresectable malignant biliary obstruction treated with percutaneous placement of a self-expanding metallic stent at our institution between May 2007 and January 2010. Serum bilirubin and liver enzyme levels were measured before and 30 days after stenting. For all procedures using elgiloy or nitinol stents, stent occlusion and patient survival rates were calculated using Kaplan-Meyer analysis. RESULTS: All of the patients showed clinical improvement after stent placement, with no difference between the two groups. In both groups, the occlusion-free survival rate was 67% at 30 days, 37% at 90 days, 25% at 180 days, and 10% at 360 days, with no significant difference in relation to the type of stent. CONCLUSION: The two stents evaluated showed comparable efficacy for the percutaneous treatment of unresectable biliary malignancy, with good clinical results.

Keywords: Radiology, interventional; Drainage; Stents; Biliary tract/pathology; Oncology.

OBJECTIVE: To evaluate the percutaneous transhepatic approach to the treatment of biliary strictures in pediatric patients undergoing liver transplantation. MATERIALS AND METHODS: This was a retrospective study of data obtained from the medical records, laboratory reports, and imaging examination reports of pediatric liver transplant recipients who underwent percutaneous transhepatic cholangiography, because of clinical suspicion of biliary strictures, between 1st September 2012 and 31 May 2015. Data were collected for 12 patients, 7 of whom were found to have biliary strictures. RESULTS: In the 7 patients with biliary strictures, a total of 21 procedures were carried out: 2 patients (28.6%) underwent the procedure twice; 3 (42.8%) underwent the procedure three times; and 2 (28.6%) underwent the procedure four times. Therefore, the mean number of procedures per patient was 3 (range, 2–4), and the average interval between them was 2.9 months (range, 0.8–9.1 months). The drainage tube remained in place for a mean of 5.8 months (range, 3.1–12.6 months). One patient presented with a major complication, hemobilia, which was treated with endovascular embolization. Clinical success was achieved in all 7 patients, and the mean follow-up after drain removal was 15.4 months (range, 5.3–26.7 months). CONCLUSION: The percutaneous transhepatic approach to treating biliary strictures in pediatric liver transplant recipients proved safe, with high rates of technical and clinical success, as well as a low rate of complications.

Keywords: Liver transplantation; Biliary atresia; Constriction, pathologic/therapy; Cholangiography; Drainage.

A large number of gadolinium chelates have recently been tested in clinical trials. Some of those have already been approved for clinical use in the United States and Europe. Thus, new diagnostic perspectives have been incorporated into magnetic resonance imaging studies. Among such gadolinium chelates are hepatobiliary-specific contrast agents (HSCAs), which, due to their property of being selectively taken up by hepatocytes and excreted by the biliary ducts, have been widely used for the detection and characterization of focal hepatic lesions. In comparison with conventional magnetic resonance cholangiography (MRC), HSCA-enhanced MRC provides additional information, with higher spatial resolution and better anatomic evaluation of a non-dilated biliary tree. A thorough anatomic assessment of the biliary tree is crucial in various hepatic surgical procedures, such as complex resection in patients with colorectal cancer and living-donor liver transplantation. However, the use of HSCA-enhanced MRC is still limited, because of a lack of data in the literature and the poor familiarity of radiologists regarding its main indications. This pictorial essay aims to demonstrate the use of HSCA-enhanced MRC, with particular emphasis on anatomical analysis of the biliary tree, clinical applications, and the most important imaging findings.

Keywords: Biliary tree; Magnetic resonance imaging; Hepatobiliary-specific contrast agents.

Most tumors of the biliary tract are too small to have specific imaging characteristics or for percutaneous puncture to provide sufficient material for diagnosis. Percutaneous transhepatic biliary drainage, in addition to being a well-established technique in the treatment of obstructive jaundice, provides adequate access for sampling obstructive lesions. In cases of biliary lesions, percutaneous transhepatic biopsy of the biliary tract has proven to be a useful diagnostic technique, with a reported accuracy of over 90% at some referral centers.

Keywords: Bile duct neoplasms; Biliary tract; Biopsy/methods; Biopsy, needle/methods; Cholangiography.

OBJECTIVE: To evaluate the accuracy of percutaneous transhepatic biliary biopsy (PTBB) in patients with suspected biliary obstruction. MATERIALS AND METHODS: This was a retrospective analysis of 18 patients with obstructive jaundice who underwent PTBB. In each patient, three to ten fragments were collected from the lesion. The final diagnosis was confirmed in the pathology report. We also reviewed analyses of the results of laboratory tests performed before the procedure, as well as the Bismuth classification, clinical outcome, complications occurring during the procedure, access route, and materials used. RESULTS: Technical success was achieved in 100% of the PTBB procedures. Among the 18 patients clinically diagnosed with bile duct stenosis, the pathological analysis confirmed that diagnosis in 17. In one case, the pathological findings were considered false-negative. The predominant tumor was cholangiocarcinoma (seen in 50% of the cases). Sixteen of the procedures (88.9%) were performed without complications. Transient hemobilia occurred in one case, and cholangitis occurred in another. CONCLUSION: PTBB is a safe, viable, simple technique with a high rate of true-positive results for the definitive diagnosis of obstructive jaundice.

Keywords: Jaundice, obstructive; Biliary tract; Biopsy/methods; Biopsy, needle/methods; Cholangiography.