Kazuhiko Ueda

[This corrects the article DOI: 10.1155/2014/607628.].

To compare radial volumetric imaging breath-hold examination with k-space weighted image contrast reconstruction (r-VIBE-KWIC) to Cartesian VIBE (c-VIBE) in arterial phase dynamic gadoxetic acid (Gd-EOB-DTPA)-enhanced magnetic resonance imaging (DCE-MRI) of the liver.

Tumor hemodynamics of carcinogenic hepatocytes nodules, that is, low grade dysplastic nodules, high grade dysplastic nodules, early hepatocellular carcinomas (HCCs), and progressed HCCs, change during multistep dedifferentiation of the nodules. Morphometric analyses of inflow vessels of these nodules indicate that the portal veins of carcinogenic hepatocyte nodules monotonically decrease whereas the arteries bitonically change, first decrease and then increase. Findings on imaging techniques depicting these changes in tumor blood inflows, especially intra-arterial contrast-enhanced computed tomography, closely related not only to the histological differentiation of the nodules but also to the outcomes of the nodules. Histological analyses of connections between the vessels within the tumors and those in the surrounding livers and findings on imaging techniques indicate that drainage vessels of HCC change from hepatic veins to hepatic sinusoids and then to portal veins during multistep hepatocarcinogenesis. Understanding of tumor hemodynamics through radio-pathological correlations will be helpful in drawing up therapeutic strategies for carcinogenic hepatocyte nodules arising in cirrhosis.

Clinicopathological conferences (CPC) are one of the most important clinical conferences, and processes of both diagnosis and treatment performed in an autopsy case are retrospectively and finely checked to offer better medical treatment in the future. In CPC, the medical history, physical findings, laboratory data, image findings, diagnosis and treatment are discussed in the order that a physician examines a patient. Differential diagnoses usually decrease and several important diagnoses remain as the CPC discussion progresses. Medical treatment is also reexamined to identify a better approach. In this CPC, several medical doctors in various special fields try to understand the detailed state of the patient from each standpoint, and such a CPC is called an Expert CPC at Shinshu University School of Medicine. This CPC is carried out followed by reversed-CPC (R-CPC) of the same case. The purpose of this CPC is to understand the importance of R-CPC and to understand the correct interpretation of routine laboratory data.

To identify characteristic magnetic resonance (MR) features of focal autoimmune pancreatitis (f-AIP) useful for differentiation from pancreatic cancer (PC). We retrospectively analyzed MR imaging findings of 20 f-AIP lesions and 40 PC lesions smaller than 40 mm in diameter. On fat-suppressed T2-weighted images and dynamic contrast-enhanced fat-suppressed T1-weighted images (DCE-T1WI), we classified MR features of internal signal intensity for each lesion into homogeneous, speckled, or target type. We assessed the sensitivity, specificity, and accuracy of these findings in the diagnosis of f-AIP. We also investigated the incidence of previously reported findings for differentiation between f-AIP and PC. Speckled enhancement within a hypointense or isointense lesion on pancreatic phase DCE-T1WI (speckled type) was observed more frequently in f-AIP than in PC, with high sensitivity, high specificity, and high accuracy. Hypointensity to hyperintensity surrounding a less enhanced focal area on DCE-T1WIs (target type) and upper stream main pancreatic duct dilatation were observed more frequently in PC than in f-AIP. Speckled enhancement inside an f-AIP lesion on pancreatic phase DCE-T1WI was useful for differentiation from PC.

We aimed to reveal the difference in contrast enhancement of the abdominal organs and major vessels on dynamic contrast-enhanced magnetic resonance imaging (DCM-MRI) using gadoxetic sodium (Gd-EOB-DTPA) and gadopentetate dimeglumine (Gd-DTPA) in the same patients. DCM-MRI using Gd-EOBDTPA and Gd-DTPA were performed in the same 17 patients. Precontrast and DCM-MRI images [arterial phase (AP), portal venous phase (PP), hepatic venous phase (HP)] were acquired before and after bolus injection of each contrast agent. The organ-to-muscle ratio [liver (L/M), spleen (S/M), aorta (A/M), portal vein (P/M), hepatic vein (V/M)] were calculated at each phase and analyzed statistically. There was no significant difference between Gd-EOB-DTPA and Gd-DTPA images regarding the L/M or V/M mean on precontrast images or the mean of L/M at AP and L/M at the PP. At the AP, PP, and HP, the means of S/M, A/M, P/M, and V/M with Gd-EOBDTPA were lower than those with Gd-DTPA. On HP, The mean L/M with Gd-EOB-DTPA was higher than that with Gd-DTPA. On 3-T DCM-MRI using Gd-EOB-DTPA, contrast enhancement of the organs, except for the liver, was lower than that on DCM-MRI using Gd-DTPA. The HP was already affected by hepatobiliary uptake in Gd-EOB-DTPA.

Liver function correlating with plasma disappearance rate of indocyanine green can be estimated quantitatively from signal intensities and volumes of liver and spleen on contrast-enhanced MR images, improving estimation of the segmental liver reserve. PurposeTo determine whether liver function correlating with indocyanine green (ICG) clearance could be estimated quantitatively from gadoxetate disodium–enhanced magnetic resonance (MR) images.Materials and MethodsThis retrospective study was approved by the institutional review board, and the requirement for informed consent was waived. Twenty-three consecutive patients who underwent an ICG clearance test and gadoxetate disodium–enhanced MR imaging with the same parameters as were used for a preoperative examination were chosen. The hepatocellular uptake index (HUI) from liver volume (VL)and mean signal intensity of the liver on contrast-enhanced T1-weighted images with fat suppression (L20) and mean signal intensity of the spleen on contrast-enhanced T1-weighted images with fat suppression (S20) on 3D gradient-echo T1-weighted images with fat suppression obtained at 20 minutes after gadoxetate disodium (0.025 mmol per kilogram of body weight) administration was determined with the following equation: VL...