Feasibility of 10-Minute Delayed Hepatocyte Phase Imaging Using a 30° Flip Angle in Gd-EOB-DTPA-Enhanced Liver MRI for the Detection of Hepatocellular Carcinoma in Patients with Chronic Hepatitis or Cirrhosis.

OBJECTIVES: To compare 10-minute (min) delayed hepatocyte phase imaging (HPI) using a 30° flip angle (FA) (10m-FA30) and 20-min delayed HPI using a 10° FA (20m-FA10) or 30° FA (20m-FA30) in Gd-EOB-DTPA-enhanced MRI in patients with chronic hepatitis or cirrhosis, in terms of lesion-to-liver contrast-to-noise ratio (CNR) for hepatocellular carcinoma (HCC) and detection sensitivity for focal hepatic lesions (FHLs). MATERIALS AND METHODS: One hundred and four patients with 168 HCCs and 55 benign FHLs who underwent Gd-EOB-DTPA-enhanced MRI with 10m-FA30, 20m-FA10, and 20m-FA30 were enrolled. Patients were divided into two groups according to the Child-Pugh classification: group A with chronic hepatitis or Child-Pugh A cirrhosis and group B with Child-Pugh B or C cirrhosis. Lesion-to-liver CNR for HCCs was compared between 10m-FA30 and 20m-FA10 or 20m-FA30 for each group. The presence of FHLs was evaluated using a four-point scale by two independent reviewers, and the detection sensitivity was analyzed. RESULTS: In group A, the CNR for HCCs (n = 86) on 10m-FA30 (165.8 ± 99.7) was significantly higher than that on 20m-FA10 (113.4 ± 71.4) and lower than that of 20m-FA30 (210.2 ± 129.3). However, there was no significant difference in the sensitivity of FHL detection between 10m-FA30 (mean 95.0% for two reviewers) and 20m-FA10 (94.7%) or 20m-FA30 (94.7%). In group B, the CNR (54.0 ± 36.4) for HCCs (n = 57) and the sensitivity (94.2%) of FHL detection for 10m-FA30 were significantly higher than those for 20m-FA10 (41.8 ± 36.4 and 80.8%, respectively) and were not different from those for 20m-FA30 (62.7 ± 44.4 and 93.3%, respectively). CONCLUSION: The diagnostic performance of 10m-FA30 was similar to or higher than 20m-FA10 or 20m-FA30 in both groups A and B. This finding indicates that 10m-FA30 could replace 20-min delayed HPI regardless of patient liver function and reduce the delay time by 10 minutes.

MR imaging features that distinguish spinal cavernous angioma from hemorrhagic ependymoma and serial MRI changes in cavernous angioma.

Cavernous angiomas of the spinal cord exhibit imaging characteristics that may overlap with those of hemorrhagic ependymoma. In the present study, we aimed to identify specific magnetic resonance imaging (MRI) findings that could be used to differentiate cavernous angioma from hemorrhagic ependymoma, and to evaluate serial MRI changes in cases of cavernous angioma. We retrospectively evaluated MR images of spinal cord tumors collected at our hospital from 2007 to 2015. From this cohort of images, 11 pathologically confirmed cavernous angiomas and 14 pathologically confirmed hemorrhagic ependymomas were compared with respect to the size of the tumor, longitudinal location, axial location, enhancement pattern, syrinx, edema, tumor margin, signal intensity of T2WI, signal intensity of T1WI, and longitudinal spreading of the hemorrhage. Serial MR images of seven spinal cavernous angiomas were reviewed. Small size, eccentric axial location, minimal enhancement, and absence of edema were more frequently observed on images of cavernous angioma compared to those of hemorrhagic ependymoma (p < 0.01). Serial MRI changes in cases of cavernous angioma included increased longitudinal spreading of the hemorrhage (6/7, 86 %) and emergence of high signal intensity on T1WI (1/7, 14 %). Small size, eccentric axial location, minimal enhancement, and absence of edema are significant MRI findings that may be used to distinguish Type I and Type II spinal cavernous angiomas from hemorrhagic ependymomas. Furthermore, longitudinal spreading of the hemorrhage may be observed on follow-up MRIs of cavernous angiomas.

The etiology of pectus carinatum involves overgrowth of costal cartilage and undergrowth of ribs.

PURPOSE: We compared the length of costal cartilage and rib between patients with symmetric pectus carinatum and controls without anterior chest wall protrusion, using a 3-dimensional (3D) computed tomography (CT) to evaluate whether the overgrowth of costal cartilage exists in patients with pectus carinatum. SUBJECTS AND METHODS: Twenty-six patients with symmetric pectus carinatum and matched twenty-six controls without chest wall protrusion were enrolled. We measured the full lengths of the 4th-6th ribs and costal cartilages using 3-D volume rendering CT images and the curved multiplanar reformatted (MPR) techniques. The lengths of ribs and costal cartilages, the summation of rib and costal cartilage lengths, and the costal index [length of cartilage/length of rib * 100 (%)] were compared between the patients group and the control group at 4th-6th levels. RESULTS: The lengths of costal cartilage in patient group were significantly longer than those of control group at 4th, 5th and 6th rib level. The lengths of ribs in patient group were significantly shorter than those of control group at 4th, 5th and 6th rib level. The summations of rib and costal cartilage lengths were not longer in patients group than in control group. The costal indices were significantly larger in patients group than in control groups at 4th, 5th and 6th rib level. CONCLUSION: In patients with symmetric pectus carinatum, the lengths of costal cartilage were longer but the lengths of rib were shorter than those of controls. These findings may supports that the overgrowth of costal cartilage was not the only factor responsible for pectus carinatum.