Pelvic Solitary Plasmacytoma: Computed Tomography and Magnetic Resonance Imaging Findings with Histopathologic Correlation

OBJECTIVE: To describe the imaging features of pelvic solitary plasmacytoma and to correlate them with the pathologic grade. MATERIALS AND METHODS: A retrospective study was performed on the imaging features of 10 patients with a histological diagnosis of pelvic solitary plasmacytoma. The imaging studies were assessed for bone expansion, cortical destruction, signal intensity/density of soft tissue mass and enhancement manifestations, which were then correlated to the pathologic grade. RESULTS: The imaging features of pelvic solitary plasmacytoma revealed 3 different types: multilocular type (n = 5), unilocular type (n = 2) and complete osteolytic destruction type (n = 3) on computed tomography and MRI. Pathologically, the tumors were classified into low, intermediate and high grades. Features such as multilocular change, perilesional osteosclerosis, slight expansion, local bone cortex disruptions and masses inside bone destruction, often suggest a low-grade solitary plasmacytoma; complete osteolytic destruction, huge soft tissue mass, and osseous defects imply a higher pathologic grade. CONCLUSION: Pelvic solitary plasmacytoma has various imaging manifestations, while a slight expansile osteolytic feature with multilocular change or homogeneous enhancement highly suggests its diagnosis. The distinctive imaging features of pelvic solitary plasmacytoma are well correlated to the pathologic grade.

Gallbladder Tuberculosis: CT Findings with Histopathologic Correlation

OBJECTIVE: We wanted to describe the computed tomography (CT) findings of gallbladder tuberculosis (TB) and to correlate them with pathologic findings. MATERIALS AND METHODS: There were seven patients (M:F = 3:4; mean age, 46.3 years; age range, 32 to 78 years) in whom gallbladder TB was eventually diagnosed. All of them underwent cross-sectional imaging with CT, a pathologic examination and a retrospective review. CT imaging evaluation was done in each case, including the findings of a mass versus nodule, wall thickening (uniform or irregular) and the enhancement patterns (homogeneous or heterogeneous). RESULTS: All the cases of gallbladder TB revealed the following three different CT findings: micronodular lesion of the gallbladder wall (n = 1), a thickened wall (n = 4) and a gallbladder mass (n = 2). There were three cases of homogeneous enhancement of the lesions, including homogeneous enhancement with nodular lesion, homogeneous uniform thickness enhancement and homogeneous thickness enhancement in one case each, and these cases pathology showed tuberculous granuloma with a little caseating necrosis in one case and tuberculous granuloma with rich fibrous tissue, but little or no evident caseating necrosis in two cases. Four cases of heterogeneous enhancement of the lesions, including heterogeneous uniform-thickness enhancement in two cases, heterogeneous enhancement with a local mass lesion in one case and heterogeneous enhancement with a mass that replaced the gallbladder in one case; in these cases, pathology showed tuberculous granuloma with marked caseation or liquefaction necrosis in three cases and tuberculous granuloma by fibrous and calcifications accompanied by caseating necrosis in one case. Among the seven cases of gallbladder TB, six cases were accompanied by abdominal extra-gallbladder TB, including abdominal lymph node TB in five cases and hepatic TB in four cases. CONCLUSION: Gallbladder TB has various CT manifestations, and the enhanced CT findings are well matched with pathological features. An irregularly thickened gallbladder wall or a gallbladder wall mass with multiple-focus necrosis or calcifications accompanied by the typical CT findings of abdominal extra-gallbladder TB should suggest the diagnosis of gallbladder TB.

Biochemical metabolic changes detected by phosphorus-31 MR spectroscopy in liver of fasting rabbits / 浙江大学学报·医学版

<p><b>OBJECTIVE</b>To investigate the biochemical metabolic changes detected by phosphorus-31 MR spectroscopy ((31)P MRS) with pathologic changes in the liver of fasting rabbits.</p><p><b>METHODS</b>A total of 22 rabbits were under the starvation up to death to establish animal models. Hepatic (31)P MRS was performed in different period of 10 rabbits including normal condition, over-starvation, agonal condition and death after 30 min. Other 9 rabbits were divided into three type including over-starvation, agonal condition and death group with 3 rabbits in each group, and 3 healthy rabbits served as controls. All the 12 rabbits were sacrificed for the hepatic pathological examination. The MR examination was performed on a 1.5 T imager using a 1H/31P surface coil by the 2D chemical shift imaging technique. The relative quantities of phosphomonoesters (PME), phosphodiesters (PDE), inorganic phosphate (Pi) and adenosine triphosphate (ATP) were measured.</p><p><b>RESULTS</b>All the relative quantification of phosphorus metabolites were changed significantly from starvation to death (X(2)=23.13-35.41, P<0.01). The relative quantifications of ATP of normal condition, over-starvation, agonal condition and death were 2.54 +/-0.53, 1.73 +/-0.14, 0.88 +/-0.23 and 0.05 +/-0.08, respectively (rs=1.0, P<0.01). The relative quantifications of PDE from normal to death were 1.25 +/-0.54, 2.76 +/-0.23, 3.33 +/-0.49 and 3.87 +/-0.43, respectively, and those of Pi were 0.42 +/-0.02, 0.65 +/-0.05, 0.89 +/-0.15 and 0.99 +/-0.08, respectively (rs=1.0, P <0.01). The relative quantifications of PME were also significantly changed (rs=0.4, P=0.6). The pathologic changes of normal condition, over-starvation, agonal condition and death: decreased size of hepatocytes, loss of cell number, cellular swelling, degeneration and cell necrosis or hepatic hemorrhage became more and more pronounced.</p><p><b>CONCLUSION</b>(31)P MRS can monitor dynamic changes of relative quantification of phosphorus metabolites, which are correlated with the pathological severity of acute hepatic injury by fasting.</p>

Evaluation of biochemical metabolites by 31P MR spectroscopy in leukemic infiltration of liver / 浙江大学学报·医学版

<p><b>OBJECTIVE</b>To evaluate the changes of phosphorus metabolites in leukemic infiltration of liver (LIL) with two-dimensional chemical shift imaging(2D CSI)(31)phosphorus MR spectroscopy ((31)P MRS).</p><p><b>METHODS</b>Fifteen patients with LIL and 12 healthy subjects (control group) were scanned with liver 2D CSI(31)P MRS by a 1.5T MR Scanner(Sonata, Siemens Corporation). Relative quantification of phosphorus metabolites including phosphomonoesters (PME), inorganic phosphate (Pi), phosphodiesters (PDE) and beta-adenosine- triphosphate (beta-ATP) were detected and after calibrated with model factor, the ratios of PME/PDE, PME/(PME+PDE), PME/ATP, PDE/ATP and Pi/ATP were analyzed.</p><p><b>RESULTS</b>Compared with control group, the PME value, PME/PDE ratio, PME/(PME+PDE) ratio and PME/ATP ratio were increased in LIL group (1.992 +/-0.876 Compared with 1.167 +/-0.427, P <0.05), (0.551 +/-0.339 Compared with 0.254 +/-0.059,P <0.01), (0.326 +/-0.13 Compared with 0.199 +/-0.049, P <0.01)and (1.402 +/-0.654 Compared with 0.792 +/-0.232, P <0.01) respectively.</p><p><b>CONCLUSION</b>(31)P MRS examination can be used as a non-invasive procedure to evaluate the changes of phosphorus metabolites of leukemic infiltration of liver. The increase of PME value and its ratios to PDE, ATP and PME+PDE may indicate leukemic infiltration of liver.</p>

CT Findings of an Ectopic Pancreas in the Anterior Mediastinum

We report here on a rare case of an ectopic pancreatic tissue in the anterior mediastinum. A 32-year-old woman without any symptoms was transferred to our hospital because of an abnormal large mediastinal shadow on her chest radiograph during a checkup. The computed tomography (CT) scan revealed a giant cystic-solid mass that measured 16 x 13 x 8 cm and it was located in the center of the anterior mediastinum and it symmetrically grew to two sides. On enhanced CT scans, the solid component of the mass showed marked enhancement. We performed total surgical resection of the mass and complete pancreatic tissues were verified on the pathological examination.

Magnetic resonance behavior of lipiodol--an experimental study / 浙江大学学报·医学版

<p><b>OBJECTIVE</b>To describe the characteristics of magnetic resonance (MR) signals generated by lipiodol and to assess the influence on MR imaging of hepatoma nodule.</p><p><b>METHODS</b>Pure lipiodol and lipiodol emulsions mixed with 76% urografin in different ratio were imaged by both CT and MR; quantitative T(1) and T(2) measurements of lipiodol were performed. Fourty-one SD rats with transplanted walker-256 sarcoma in liver were randomly divided into six groups: 0.4-0.6 ml lipiodol emulsion was infused via hepatic artery in experimental groups by means of laparotomy under celiac anesthesia. The changes in MRI signal of hepatoma nodule were observed.</p><p><b>RESULT</b>In vitro, iodized oil demonstrated high signal on T(1)-weighted images when performed at 37 degree, but all could be suppressed by the fat saturation sequence, and showed very low signal on T(2)-weighted images. The characteristic of MR signal with ultra fluid lipiodol was different from that of iodized oil (P<0.01), showing short T(1) and long T(2) signal; the high signal on T(1)-weighted images was only partially suppressed by the fat saturation sequence. With descending ratio of lipiodol in emulsion, the signal behavior was gradually similar to urografin (r -0.958, P<0.01). When rats were transarterially infused with emulsion, the intensity of the signal on MRI was nearly the same as that in the control rats, but when lipiodol was injected out of the hepatic artery and accumulated in lymphadenopathy, it demonstrated a signal similar to fat; the high intensity signal was maintained on T(1)-weighted images and T(2)-weighted images.</p><p><b>CONCLUSION</b>There are little changes in MR signal intensity when the lipiodol is accumulated in the tumor nodules. MR behavior of lipiodol is determined by its deposit area.</p>