Hepatocellular carcinoma in patients undergoing living-donor liver transplantation. Accuracy of multidetector computed tomography by viewing images on digital monitors.

OBJECTIVE: To compare 8-detector row helical computed tomography (CT) findings with histopathology in patients with hepatocellular carcinoma (HCC) who had undergone living-donor liver transplantation (LDLT). MATERIALS AND METHODS: This institutional review board-approved prospective study was performed between February 12, 2003 and November 12, 2004; of the 78 candidates for LDLT due to HCC who underwent preoperative multidetector CT (MDCT), 48 transplant recipients met our criteria and in 41 of them, HCCs were diagnosed with <15 lesions on MDCT; these patients represented the study population. Results of preoperative CT were correlated with histopathological results after 5-mm sagittal slicing of the explanted liver. Following the injection of contrast medium (2 ml/kg body weight of 300 mg I/ml), triple-phase contrast-enhanced images were obtained. CT was performed using the following parameters: detector row configuration, 8 x 1 mm, reconstruction interval, 1 mm, 200 mA s and 120 kVp. Image analysis was performed in consensus by three abdominal radiologists using 1-mm-thick slices with 0.5-mm overlap with paging as well as multiplanar reformatting (MPR; i.e. axial, coronal and sagittal images). RESULTS: A total of 134 HCCs were identified by pathological examination. The mean lesion size was 21 mm. Sensitivity, positive predictive value and accuracy for HCC detection were 87, 96 and 84% for all lesions, respectively, and 99, 100 and 97% for lesions >1 cm, respectively, but only 46, 76 and 41% for tumors <1 cm, respectively (n = 28). There were 12 false-negative lesions but only 5 false-positive findings. CONCLUSION: MDCT combined with the paging method and MPR images is very effective in the detection of HCCs >1 cm in diameter with a very low false-positive rate.

CT laparoscopy for detecting small superficial metastatic lesions of the liver surface: initial experience.

OBJECTIVE: The purpose of this study was to determine the efficacy of CT laparoscopy in the detection of superficial metastasis of the liver surface. SUBJECTS AND METHODS: From April 1, 2007, to July 1, 2007, a total of 34 consecutively registered patients (19 men, 15 women; median age, 55 years) with various intraabdominal malignant tumors underwent preoperative CT and composed the study population. All patients underwent superparamagnetic iron oxide-enhanced MRI and portal phase contrast-enhanced 64-MDCT, including CT laparoscopy. CT laparoscopy is a form of volume-rendering 3D imaging of the liver that depicts the liver surface in detail. RESULTS: Among 23 patients who underwent surgery for management of a primary tumor, four patients had seven superficial metastatic lesions of the liver surface. None of these lesions had been detected with preoperative axial CT or superparamagnetic iron oxide-enhanced MRI. In contrast, CT laparoscopy revealed four of seven lesions in four patients. On a lesion-by-lesion basis, the sensitivity was 57%, the positive predictive value was 100%, and the accuracy was 57%. CONCLUSION: Our initial experience proves that CT laparoscopy is a promising method for detecting small superficial metastatic lesions of the liver surface. The findings can influence decisions regarding tumor resectability.

Left Gastric Vein Visualization with Hepatopetal Flow Information in Healthy Subjects Using Non-Contrast-Enhanced Magnetic Resonance Angiography with Balanced Steady-State Free-Precession Sequence and Time-Spatial Labeling Inversion Pulse

OBJECTIVE: To selectively visualize the left gastric vein (LGV) with hepatopetal flow information by non-contrast-enhanced magnetic resonance angiography under a hypothesis that change in the LGV flow direction can predict the development of esophageal varices; and to optimize the acquisition protocol in healthy subjects. MATERIALS AND METHODS: Respiratory-gated three-dimensional balanced steady-state free-precession scans were conducted on 31 healthy subjects using two methods (A and B) for visualizing the LGV with hepatopetal flow. In method A, two time-spatial labeling inversion pulses (Time-SLIP) were placed on the whole abdomen and the area from the gastric fornix to the upper body, excluding the LGV area. In method B, nonselective inversion recovery pulse was used and one Time-SLIP was placed on the esophagogastric junction. The detectability and consistency of LGV were evaluated using the two methods and ultrasonography (US). RESULTS: Left gastric veins by method A, B, and US were detected in 30 (97%), 24 (77%), and 23 (74%) subjects, respectively. LGV flow by US was hepatopetal in 22 subjects and stagnant in one subject. All hepatopetal LGVs by US coincided with the visualized vessels in both methods. One subject with non-visualized LGV in method A showed stagnant LGV by US. CONCLUSION: Hepatopetal LGV could be selectively visualized by method A in healthy subjects.

Biliary Peritonitis after Radiofrequency Ablation Diagnosed by Gadoxetic Acid-Enhanced MR Imaging

This study describes the first case of biliary peritonitis after radiofrequency ablation diagnosed by magnetic resonance (MR) imaging with gadolinium ethoxybenzyl diethylenetriaminepentaacetic acid (Gd-EOB-DTPA), a hepatocyte-specific MR imaging contrast agent. The image acquired 300 minutes after the administration of Gd-EOB-DTPA was useful to make a definite diagnosis and to identify the pathway of bile leakage. It is important to decide on the acquisition timing with consideration of the predicted location of bile duct injury.