Volumetric low-tube-voltage CT imaging for evaluating hypervascular hepatocellular carcinoma; effects on radiation exposure, image quality, and diagnostic performance.

Objectives: To assess the value of hepatic arterial-phase (HAP) imaging with a low tube voltage (80 kVp), using non-helical, volumetric acquisition with a 320-detector-rows area-detector CT (ADCT) scanner for evaluating hypervascular hepatocellular carcinoma (HCC) compared with routine 120-kVp HAP imaging.

Methods: This study enrolled 128 patients with 148 HCCs. Seventy-six patients with 79 HCCs underwent HAP imaging with 80 kVp obtained using a 320-detector-rows ADCT scanner.

Diffusion-weighted imaging of hepatocellular carcinoma for predicting early recurrence and survival after hepatectomy.

Purpose: The effectiveness of imaging (including apparent diffusion coefficient [ADC] of diffusion-weighted magnetic resonance imaging [DWI]) and laboratory variables for predicting early tumor recurrence and overall survival after surgery in hepatocellular carcinoma (HCC) patients are analyzed.

Methods: The present study included 116 consecutive patients with HCC who underwent partial hepatectomy. Patients were classified into two groups: patients with and without early recurrence (<1 year).

Diffusion- and T₂-weighted MR imaging of the liver: effect of intravenous administration of gadoxetic acid disodium.

Purpose: We evaluated the effect of intravenous administration of gadoxetic acid disodium to hepatic lesions and liver parenchyma on T₂-weighted (T₂WI) and diffusion-weighted imaging (DWI).

Materials And Methods: One hundred and one consecutive patients with 259 hepatic lesions underwent T₂WI and DWI (b-values of 500 and 1000 s/mm²) before and after gadoxetic acid administration. We compared the ratio of signal intensity (SIR) of the liver parenchyma and hepatic lesions, the ratio of contrast intensity of the lesion to the liver (CIR), the apparent diffusion coefficients (ADCs) of the liver and lesions, and lesion detectability between pre- and post-contrast images.

Magnetic resonance elastography as a predictor of insufficient liver enhancement on gadoxetic acid-enhanced hepatocyte-phase magnetic resonance imaging in patients with type C hepatitis and Child-Pugh class A disease.

Objectives: The aim of this study was to examine liver stiffness value measured by magnetic resonance elastography (MRE) and laboratory test results to find the best method for predicting insufficient liver enhancement on gadoxetic acid-enhanced hepatocyte-phase images.

Materials And Methods: The institutional ethics committee approved this retrospective study with waiver of informed consent. In total, 118 patients with Child-Pugh class A disease and type C hepatitis underwent MRE and gadoxetic acid-enhanced magnetic resonance imaging.

Diffusion-weighted imaging in optic neuritis.

Purpose: To evaluate imaging characteristics of optic nerves by using magnetic resonance imaging, especially diffusion-weighted imaging (DWI) with apparent diffusion coefficient measurements in acute and chronic phases of optic neuritis (ON).

Materials And Methods: A retrospective study was conducted by using records of 14 patients with clinically suspected acute ON (15 nerves), 5 chronic ON (7 nerves), and 11 normal volunteers with no eye symptoms were used as controls. Magnetic resonance imaging was performed by a 1.

Mass-forming autoimmune pancreatitis and pancreatic carcinoma: differential diagnosis on the basis of computed tomography and magnetic resonance cholangiopancreatography, and diffusion-weighted imaging findings.

Purpose: To differentiate mass-forming autoimmune pancreatitis (AIP) from pancreatic carcinoma by means of analysis of both computed tomography (CT) and magnetic resonance imaging (MRI) findings.

Materials And Methods: Ten patients with mass-forming AIP diagnosed by revised clinical criteria of Japan Pancreas Society and 70 patients with pathologically proven pancreatic carcinoma were enrolled in this retrospective study. Two radiologists independently evaluated the CT and MR imaging findings.

Cross-validation of MR elastography and ultrasound transient elastography in liver stiffness measurement: discrepancy in the results of cirrhotic liver.

Purpose: To evaluate individual differences in liver stiffness measurement using both MR elastography (MRE) and ultrasound transient elastography (UTE) in patients with chronic liver disease.

Materials And Methods: This study included 80 patients with chronic liver disease who underwent both UTE and MRE. MRE and UTE were performed using a pneumatic driver (60 Hz) and an ultrasound probe with a vibrator (50 Hz), respectively.

Imaging study of early hepatocellular carcinoma: usefulness of gadoxetic acid-enhanced MR imaging.

Purpose: To describe imaging findings of early hepatocellular carcinoma (HCC) at gadoxetic acid-enhanced magnetic resonance (MR) imaging, dynamic contrast material-enhanced computed tomography (CT), CT during arterial portography (CTAP), and CT during hepatic arteriography (CTHA) and to compare the diagnostic performance of each modality for small (≤ 2 cm) HCC.

Materials And Methods: The institute ethics committee deemed study approval unnecessary. One hundred eight resected small lesions in 64 patients were diagnosed as a dysplastic nodule (DN) (n = 12), progressed HCC (n = 66), or early HCC (n = 30).

Effects of gadoxetic acid on liver elasticity measurement by using magnetic resonance elastography.

The purpose of this study was to evaluate the effect of gadoxetic acid (Gd-EOB-DTPA) on measurements of liver stiffness by using magnetic resonance elastography (MRE). In this study, 104 consecutive patients (mean age, 67.7±9.

Diagnosis of colorectal hepatic metastases: comparison of contrast-enhanced CT, contrast-enhanced US, superparamagnetic iron oxide-enhanced MRI, and gadoxetic acid-enhanced MRI.

Purpose: To compare the diagnostic accuracy of contrast-enhanced computed tomography (CE-CT), contrast-enhanced ultrasonography (CE-US), superparamagnetic iron oxide-enhanced magnetic resonance imaging (SPIO-MRI), and gadoxetic acid-enhanced MRI (Gd-EOB-MRI) in the evaluation of colorectal hepatic metastases.

Materials And Methods: In all, 111 patients with colorectal cancers were enrolled in this study. Of the 112 metastases identified in 46 patients, 31 in 18 patients were confirmed histologically and the remaining 81 in 28 patients were confirmed by follow-up imaging.

Staging liver fibrosis by using liver-enhancement ratio of gadoxetic acid-enhanced MR imaging: comparison with aspartate aminotransferase-to-platelet ratio index.

Objective: To compare the diagnostic ability of gadoxetic acid-enhanced hepatocyte-phase MR images with aspartate aminotransferase-to-platelet ratio index (APRI) to predict liver fibrosis stage.

Materials And Methods: Our study included 100 patients who underwent gadoxetic acid-enhanced MRI and either liver biopsy or liver surgery. Liver fibrosis stage was histologically determined according to the METAVIR system: F0 (n=16), F1 (n=17), F2 (n=10), F3 (n=21) and F4 (n=36).

Detection of pancreatic carcinoma and liver metastases with gadoxetic acid-enhanced MR imaging: comparison with contrast-enhanced multi-detector row CT.

Purpose: To intraindividually compare gadoxetic acid-enhanced magnetic resonance (MR) imaging with contrast material-enhanced multi-detector row computed tomography (CT) in detection of pancreatic carcinoma and liver metastases.

Materials And Methods: The ethics committee approved this retrospective study with waiver of informed consent. This study included 100 patients (53 men, 47 women; mean age, 67.

Outcome of hypovascular hepatic nodules revealing no gadoxetic acid uptake in patients with chronic liver disease.

Purpose: To elucidate the natural history of hypovascular nodules that appear hypointense on hepatocyte-phase gadoxetic acid-enhanced MR images by focusing on hypervascularization over time.

Materials And Methods: In this study, 135 hypovascular nodules revealing no gadoxetic acid uptake in 53 patients were examined. All nodules were retrospectively examined using serial follow-up computed tomography (CT) and MRI examinations until hypervascularity was observed on arterial-phase dynamic CT or gadoxetic acid-enhanced MR images, or on CT during hepatic arteriography.

Distinguishing hepatic metastasis from hemangioma using gadoxetic acid-enhanced magnetic resonance imaging.

Purpose: To retrospectively determine the findings of gadoxetic acid-enhanced magnetic resonance imaging (MRI) to distinguish hemangioma and metastasis of the liver.

Materials And Methods: The University's ethics committee approved this retrospective study. We assessed 45 patients without chronic liver disease who underwent gadoxetic acid-enhanced MRI.

Double-dose gadoxetic Acid-enhanced magnetic resonance imaging in patients with chronic liver disease.

Objectives: determine the effect of double-dose gadoxetic-acid (Gd-EOB-DTPA) on lesion-liver contrast ratio in arterial- and hepatocyte-phase images and arterial-phase image quality in patients with chronic liver disease.

Materials And Methods: the ethics committee at our institute approved this study. This study included 28 patients (13 with Child-Pugh class A and 15 with class B) with 54 hepatocellular carcinomas.

Diagnosis of colorectal hepatic metastases: Contrast-enhanced ultrasonography versus contrast-enhanced computed tomography versus superparamagnetic iron oxide-enhanced magnetic resonance imaging with diffusion-weighted imaging.

Purpose: To compare the diagnostic accuracy of contrast-enhanced ultrasonography (CE-US), contrast-enhanced CT (CE-CT), and superparamagnetic iron oxide-enhanced MRI (SPIO-MRI) with diffusion-weighted imaging (DWI) in the evaluation of colorectal hepatic metastases.

Materials And Methods: Thirty-six patients with colorectal cancers were prospectively enrolled and retrospectively evaluated. Of the 86 metastases identified, 16 were confirmed histologically and the remaining 70 were confirmed by follow-up imaging.

Magnetic resonance elastography of the liver: preliminary results and estimation of inter-rater reliability.

Purpose: The aim of this study was to estimate inter-rater reliability and validate magnetic resonance elastography (MRE) as a tool to measure liver elasticity.

Materials And Methods: The study protocol was approved by the institutional review board at our institution. In all, 10 normal volunteers and 110 patients, who provided written informed consent, were enrolled.

Distinguishing hypervascular pseudolesions of the liver from hypervascular hepatocellular carcinomas with gadoxetic acid-enhanced MR imaging.

Purpose: To retrospectively determine findings at gadoxetic acid-enhanced magnetic resonance (MR) imaging in hypervascular pseudolesions that were observed at computed tomography (CT) during hepatic arteriography, with special focus on distinguishing these pseudolesions from hypervascular hepatocellular carcinomas (HCCs).

Materials And Methods: The institute ethics committee deemed study approval unnecessary. The study population comprised 80 patients (55 men, 25 women) with chronic liver disease who underwent CT during hepatic arteriography and arterial portography, gadoxetic acid-enhanced MR imaging, and follow-up dynamic contrast material-enhanced CT.

High-b-value diffusion-weighted MR imaging of hepatocellular lesions: estimation of grade of malignancy of hepatocellular carcinoma.

Purpose: To evaluate the effectiveness of diffusion-weighted magnetic resonance imaging (DWI) in estimating the grade of malignancy of hepatocellular carcinoma.

Materials And Methods: Dynamic contrast-enhanced computed tomography (CE-CT) and DWI (b value, 1000 s/mm(2)) were performed on 73 patients. Using DW images, the lesions were classified as "visible" or "invisible.