Automated MR spectroscopy of intra- and extraventricular neurocytomas.

Purpose: We evaluated the automated magnetic resonance spectroscopic (MRS) characteristics of intra- and extraventricular neurocytomas.

Materials And Methods: One extra- and 4 intraventricular neurocytomas were studied. Automated single-voxel proton MRS was performed with a 1.

Comparison between 3-D and z-axis automatic tube current modulation technique in multidetector-row CT.

In this study, the 3-D automatic tube current modulation (3-D ATCM) technique was compared with the z-axis ATCM technique on multidetector-row CT. Absorbed dose measurements were performed by inserting an ion chamber into the phantoms, and objective image noise shown as the standard deviation of CT value in Hounsfield units was measured on the obtained images. The ratio of absorbed doses with 3-D ATCM technique to z-axis ATCM technique was 94.

Hemodynamics of small sclerosing hepatocellular carcinoma without fibrous capsule: evaluation with single-level dynamic CT during hepatic arteriography.

The tumor drainage pathway of a hypervascular liver tumor without fibrous capsule was evaluated histologically and using single-level dynamic CT during hepatic arteriography (CTHA) in a case of sclerosing type of hepatocellular carcinoma. This tumor had a thin corona on CTHA, which represented drainage from the tumor sinusoids to the surrounding liver sinusoids. Additionally, the corona of the hypervascular tumor was thinner without than with the fibrous capsule.

Vascular endothelial growth factor, its receptor Flk-1, and hypoxia inducible factor-1alpha are involved in malignant transformation in dysplastic nodules of the liver.

Dysplastic nodules (DNs) are regarded as a premalignant lesion of hepatocellular carcinoma (HCC). Sinusoidal capillarization and unpaired arteries are reported in HCC and also to a lesser degree in DN. However, the mechanism and significance of these vascular alterations remain unclear.

Enhancement patterns and signal-intensity characteristics of small hepatocellular carcinoma in cirrhosis: pathologic basis and diagnostic challenges.

Recent pathologic studies of hepatic resection and transplantation specimens have elucidated the morphologic features of the precancerous lesions and small hepatocellular carcinomas (HCCs) arising in cirrhotic livers. Small HCCs measuring less than 2 cm in diameter are of two types: vaguely nodular, well-differentiated tumors, also known as "early" HCCs, and distinctly nodular tumors, with histologic features of "classic" HCC. The precancerous lesions include dysplastic foci and dysplastic nodules.

Imaging diagnosis of hepatic metastases of pancreatic carcinomas: significance of transient wedge-shaped contrast enhancement mimicking arterioportal shunt.

We aimed to evaluate the imaging findings of hepatic metastases from pancreatic cancers, especially wedge-shaped enhancement and its etiology. Dynamic CT and MR images were performed in 87 patients with liver metastases from pancreatic carcinomas, and CT during arterial portography (CTAP) and CT during hepatic arteriography (CTHA) in 51 patients. Liver metastases were multiple in 84 patients (97%) and solitary in only three (3%).

A subgroup of intrahepatic cholangiocarcinoma with an infiltrating replacement growth pattern and a resemblance to reactive proliferating bile ductules: 'bile ductular carcinoma'.

Aims: The histogenesis and biological behaviour of peripheral intrahepatic cholangiocarcinoma (peripheral CC) remain unclarified. The aim of this study was to examine the growth pattern of peripheral CC (24 cases) in comparison with hepatocellular carcinoma (HCC, 27 cases) and metastatic colorectal adenocarcinoma (MCA, 24 cases).

Methods And Results: Tumour/surrounding liver borders were classified as: (i) fibrous encapsulation, (ii) compressive growth, and (iii) infiltrating replacement.

Significance of enhanced expression of nitric oxide syntheses in splenic sinus lining cells in altered portal hemodynamics of idiopathic portal hypertension.

Idiopathic portal hypertension (IPH) is characterized by noncirrhotic portal hypertension due mainly to increased intrahepatic, presinusoidal resistance to portal blood flow. Marked splenomegaly is always seen in IPH. To clarify the pathogenetic significance of splenomegaly, immunohistochemical expression of inducible nitric oxide synthese (iNOS), endothelial NOS (eNOS), and endothelin-1 (ET-1) in spleens from patients with IPH was examined.

Ultraselective transcatheter arterial chemoembolization with a 2-f tip microcatheter for small hepatocellular carcinomas: relationship between local tumor recurrence and visualization of the portal vein with iodized oil.

Purpose: To retrospectively evaluate the relationship between local tumor recurrence and iodized oil deposition in the portal vein by using ultraselective transcatheter arterial chemoembolization (TACE) for small hepatocellular carcinoma.

Materials And Methods: One-hundred twenty-three tumors smaller than 5 cm in diameter (mean diameter, 1.9 cm; median diameter, 1.

Detectability of regional lung ventilation with flat-panel detector-based dynamic radiography.

This study was performed to investigate the ability of breathing chest radiography using flat-panel detector (FPD) to quantify relative local ventilation. Dynamic chest radiographs during respiration were obtained using a modified FPD system. Imaging was performed in three different positions, ie, standing and right and left decubitus positions, to change the distribution of local ventilation.

Changes of intratumoral microvessels and blood perfusion during establishment of hepatic metastases in mice.

Purpose: To prospectively evaluate the stepwise changes that occur in intratumoral microvessels and microcirculation during the establishment of murine colonic hepatic metastases by using in vivo fluorescent microscopy and to compare the changes with tumor angiogenesis evaluated with an immunohistochemical study.

Materials And Methods: This study was approved by the institutional animal care and use committee. Twenty-five mice with hepatic metastases created with injection of murine colonic adenocarcinoma (colon 26) tumor cells into the spleen were examined with in vivo microscopy and immunohistochemical study for CD34, intracellular adhesion molecule (ICAM-1), and alpha smooth muscle actin (alpha-SMA).

Portosystemic shunt on CT during arterial portography: prevalence in patients with and without liver cirrhosis.

Background: To review various portosystemic shunts (PS) and to evaluate their prevalence by CT during arterial portography (CTAP) using a multidetector-row CT (MDCT).

Methods: CTAP of 116 patients (liver cirrhosis 70 patients, non-liver cirrhosis 46 patients) was retrospectively reviewed. CTAP was performed with the catheter placed in the superior mesenteric artery using MDCT.

Combined therapy of transcatheter hepatic arterial embolization with intratumoral dendritic cell infusion for hepatocellular carcinoma: clinical safety.

The curative treatments for hepatocellular carcinoma (HCC), including surgical resection and radiofrequency ablation (RFA), do not prevent tumour recurrence effectively. Dendritic cell (DC)-based immunotherapies are believed to contribute to the eradication of the residual and recurrent tumour cells. The current study was designed to assess the safety and bioactivity of DC infusion into tumour tissues following transcatheter hepatic arterial embolization (TAE) for patients with cirrhosis and HCC.

Spontaneous hemothorax in neurofibromatosis treated with percutaneous embolization.

We evaluated the effectiveness of transcatheter arterial coil embolization therapy for the treatment of spontaneous hemothorax followed by aneurysm rupture in neurofibromatosis patients. Three patients were treated for massive hemothorax caused by arterial lesions associated with neurofibromatosis. Bleeding episodes were secondary to ascending cervical artery aneurysm and dissection of vertebral artery in 1 patient, and intercostal artery aneurysm with or without arteriovenous fistula in 2 patients.

MR imaging of hepatocellular carcinomas with biliary tumor thrombi.

We retrospectively evaluate the MR imaging findings of hepatocellular carcinomas (HCC) with biliary tumor thrombi. MR imaging was performed on six patients presenting with obstructive jaundice and/or biliary hemorrhage. T1-weighted images, T2-weighted images, MR cholangiopancreatography (MRCP), and dynamic MR images were obtained.

Autoimmune pancreatitis with multifocal mass lesions.

Autoimmune pancreatitis (AIP) is radiologically characterized as diffuse swelling of the pancreatic parenchyma and irregular narrowing of the pancreatic ducts. We present a case of AIP with multiple small nodular lesions in the pancreas. This case suggests that AIP with only small nodular or localized lesions is more difficult to differentiate from pancreatic cancer than typical cases of AIP.

A computer-aided temporal and dynamic subtraction technique of the liver for detection of small hepatocellular carcinomas on abdominal CT images.

It is often difficult for radiologists to identify small hepatocellular carcinomas (HCCs) due to insufficient contrast enhancement. Therefore, we have developed a new computer-aided temporal and dynamic subtraction technique to enhance small HCCs, after automatically selecting images set at the same anatomical position from the present (non-enhanced and arterial-phase CT images) and previous images. The present study was performed with CT images from 14 subjects.

Evaluation of pulmonary function using breathing chest radiography with a dynamic flat panel detector: primary results in pulmonary diseases.

Objectives: Dynamic flat panel detectors (FPD) permit acquisition of distortion-free radiographs with a large field of view and high image quality. The present study was performed to evaluate pulmonary function using breathing chest radiography with a dynamic FPD. We report primary results of a clinical study and computer algorithm for quantifying and visualizing relative local pulmonary airflow.

Focal hepatic lesions mimicking cavernous hemangioma supplied by the portal vein.

We report that imaging findings of focal hepatic lesion mimicking cavernous hemangioma supplied by the portal vein, which showed delayed enhancement on CT and hyperintensity similar to that of cerebrospinal fluid on T2-weighted MR images. Biopsy specimen showed the dilated portal veins and hyperplastic change in the surrounding liver parenchyma. CT during arterial portography (CTAP), in particular single-level dynamic CTAP, could clearly depict the abnormal dilated portal vein in the lesion and facilitated the diagnosis of this condition.

Peliosis hepatis: spectrum of imaging findings.

Objective: It is important to recognize the imaging characteristics of peliosis hepatis because peliotic lesions may mimic several different types of focal hepatic lesions

Conclusion: We illustrate the spectrum of imaging findings of peliosis hepatis, including sonography, CT, MR, and angiography.

Anatomical study of the occipital sinus using contrast-enhanced magnetic resonance venography.

The frequency and anatomical features of the occipital sinus (OS) were analyzed in this study by contrast-enhanced magnetic resonance venography (MRV) with enhanced fast gradient echo three-dimensional (EFGRE3D) and we discuss the clinical usefulness of this method. The study included 555 patients who underwent contrast-enhanced MRV with EFGRE3D, and maximum intensity projection (MIP), multiplanar reformation (MPR) and multiprojection volume reconstruction (MPVR) images were obtained for the regions of interest. The frequency, size and communication of the OS with other vessels were assessed.

Bronchial artery aneurysm embolization with NBCA.

We present a case of asymptomatic bronchial artery aneurysm that formed a fistula with part of the pulmonary artery (there was no definite fistula with the pulmonary vein). We were able to catheterize the feeding vessel but could not reach the aneurysm. We therefore injected a mixture of N-butyl-2-cyanoacrylate (NBCA; Histoacryl, B.

Clinical Application of an Original Flexible MK Stent-Graft For Nonruptured Thoracic Aortic Aneurysms: Early Experience.

Objective: : To obtain early MK stent-grafting results for nonruptured thoracic aortic aneurysms and thoracoabdominal aortic aneurysms.

Methods: : The authors analyzed 47 patients who underwent treatment using MK stent-grafting. All patients (40 men and 7 women; mean age, 70.