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PURPOSE Our aim was to compare the inter-observer and intra-observer variability for the measurement of the size of liver metastases in patients with carcinoid tumors with various MR series. METHOD AND MATERIALS In this, retrospective IRB approved study, 30 patients with liver metastases from a carcinoid primary had a complete MR examination of the abdomen at 1.5T with Gd-EOB-DTPA. The complete MR examination included: T1 (in/out-of-phase, T2, DWI, Pre- and Post-Gd-EOB-DTPA 3D gradient echo (4 phases plus 20min (HBP-Gd). Four readers review each series independently. The measurement for each lesion was compared to HBP-Gd images. The sensitivity for detection of each lesion was compared to HBP-Gd. Variance component analysis was used to estimate variance due to patient, lesion within patient, and reader by sequence. Linear mixed model was used to compare lesion size between sequences. RESULTS The HBP-Gd had the smallest inter-reader variability. There was no significant difference between series with respect to inter-reader variability. Lesion sizes measured in DWI was significantly higher. T2W was the closest to HBP-Gd. Lesion sizes measured with the other sequences were significantly smaller. There was significantly difference in sensitivity of lesion detection of some series when compared to HBP-Gd. CONCLUSION HBP-Gd series had the smallest inter-reader variability and is the recommended series to measure lesion size for evaluation of response to treatment.

The Brazilian Gastrointestinal Tumor Group developed guidelines for the surgical and clinical management of patients with billiary cancers. The multidisciplinary panel was composed of experts in the field of radiology, medical oncology, surgical oncology, radiotherapy, endoscopy and pathology. The panel utilized the most recent literature to develop a series of evidence-based recommendations on different treatment and diagnostic strategies for cholangiocarcinomas and gallbladder cancers.

Chemotherapy is a potential cause of focal and diffuse hepatobiliary lesions. Many of these lesions may be demonstrated on imaging, especially computed tomography and MRI. Some of these lesions, especially those of steatosis and sinusoidal obstruction syndrome, are associated with a worse prognosis and risk of hepatic failure in the context of surgical management. Notably, some chemotherapy-induced hepatic alterations, such as sinusoidal obstruction syndrome, pseudocirrhosis and focal hepatopathies, may be mistakenly interpreted as signs of cancer progression, misguiding the therapeutic planning for patients receiving chemotherapy.

Cross-sectional imaging with computed tomography or magnetic resonance imaging is routinely used to detect and diagnose liver lesions; however, these examinations can provide additional important information. The improvement of equipment and techniques has allowed outstanding evaluation of the vascular and biliary anatomy, which is practicable in most routine examinations. Anatomical variants may exclude patients from certain therapeutic options and may be the cause of morbidity or mortality after surgery or interventional procedures. Diffuse liver disease, such as steatosis, hemochromatosis, or fibrosis, must be diagnosed and quantified. Usually these conditions are silent until the late stages, and imaging plays an important role in detecting them early. Additionally, a background of diffuse disease may interfere in a focal lesion systematic reasoning. The diagnostic probability of a particular nodule varies according to the background liver disease. Nowadays, most diffuse liver diseases can be easily and accurately quantified by imaging, which has allowed better understanding of these diseases and improved patient management. Finally, cross-sectional imaging can calculate total and partial liver volumes and estimate the future liver remnant after hepatectomy. This information helps to select patients for portal vein embolization and reduces postoperative complications. Use of a specific hepatic contrast agent on magnetic resonance imaging, in addition to improving detection and characterization of focal lesions, provides functional global and segmental information about the liver parenchyma.

AIMTo evaluate the correlation between degree of kinetic growth (kGR) of the liver following portal vein embolization (PVE) liver and the enhancement of the during the hepatobiliary phase of contrast administration and to evaluate if the enhancement can be used to predict response to PVE prior to the procedure.METHODSSeventeen patients were consented for the prospective study. All patients had an MR of the abdomen with Gd-EOB-DTPA. Fourteen patients underwent PVE. The correlation between the kGR of the liver and the degree of enhancement was evaluated with linear regression (strong assumptions) and Spearman’s correlation test (rank based, no assumptions). The correlation was examined for the whole liver, segments I, VIII, VII, VI, V, IV, right liver and left liver.RESULTSThere was no correlation between the degree of enhancement during the hepatobiliary phase and kGR for any segment, lobe of the liver or whole liver (P = 0.19 to 0.91 by Spearman’s correlation test).CONCLUSIONThe relative enhancement of the liver during the hepatobiliary phase with Gd-EOB-DTPA cannot be used to predict the liver response to PVE.

Collision tumors are defined as the presence of two contiguous histologically different lesions composed of benign and/or malignant components. They are infrequent entities and have been reported in various organs and systems. The most common type of collision tumor in the adrenal gland is the association of two benign lesions, adenoma and myelolipoma. Modification in image characteristics or unexpected growth of an adrenal tumor previously characterized as a benign lesion should be suspicious for collision tumor with a new aggressive component. In this article, we present a case of renal carcinoma metastasis within a previously known adrenal adenoma.

A técnica de dissecção de fibras é um método clássico, utilizado por renomados anatomistas do passado, para a demonstração dos tratos e fascículos integrantes da substância branca do cérebro. Esta técnica, utilizada desde o século XVII, envolve a dissecção em camadas da substância branca cerebral para demonstrar passo a passo a organização anatômica interna do parênquima. A complexidade da preparação do cérebro e da dissecção das fibras fez com que esse método fosse negligenciado por décadas. Com a possibilidade contemporânea e inédita de se visualizar os feixes de substância branca do encéfalo in vivo pela ressonância magnética, os fundamentos anatômicos antigos obtidos com a clássica técnica de dissecção de fibras tornam-se, paradoxalmente, ainda mais relevantes e atuais. Este trabalho descreve as principais etapas da técnica de dissecção de fibras, aprimorada por Joseph Klingler e revitalizada na última década por M. G. Yasargil e Ügur Türe, como uma forma de entendimento da anatomia intrínseca tridimensional do encéfalo para o uso clínico. Este estudo também busca explorar as potencialidades dessa verdadeira “dissecção virtual” através da ressonância magnética (tratografia) em reproduzir e complementar o conhecimento anatômico das fibras obtido pelo método clássico.