Objective To study spiral CT features and pathological basis of nodular goiter ,so that to improve the diagnostic accuracy of nodular goiter.Methods CT findings in 34 patients with nodular goiter confirmed by pathology were retrospectively analyzed and compared with pathological findings. Results Thyroid density in the patients with NG was lower than that in the normal. There was no statistically significant difference in the density between single and multi-NG. Most lesions(28/34) were multiple, round or oval, with different size and smooth edges. The density of majority lesions was lower than nearby normal tissue. Most lesions (27/34) were uniform in density. Central necrosis(5/34)often appeared in the bigger lesions(diameter＞3.0 cm). The CT value of the lesions was increased (47.1±42.2) HU after enhancement,but lower than surrounding thyroid tissue. Calcifications in the lesions(6/34)were puncticular,plaque or crustiform. Single or multiple cystic-solid or solid nodules could be seen in pathology, without a continuous capsule in the majority. Some patients (5/13) with single NG shown on imaging study were multi-NG in the pathology. Three cases of diffuse NG showed by CT were malignant in pathology. Conclusion There are certain characteristics for NG on spiral CT. Comprehensive evaluation may improve the accuracy of CT diagnosis.

OBJECTIVETo investigate the methods for assessing angiogenesis in experimental liver fibrosis.

METHODSMale C57BL/6 mice were randomly divided into a normal (unmodeled) group and a liver fibrosis model group.The model was established by a 4-week course of 10% CCl4 solution (in olive oil) intraperitoneal injection. Liver vasculature was observed by magnetic resonance (MR),computed tomography (CT),synchrotron radiation X-ray,and von Willibrand factor(vWF) immunofluorescence staining. Liver inflammation and fibrosis were observed by staining with hematoxylin-eosin and Sirius red.The t-test and Pearson's correlation analysis were used for statistical analyses.

RESULTSCompared with the normal group,the model group had more robust inflammation and fibrosis in liver tissue.The liver tissue in the modeled mice showed significant deceases in MR signal intensity on T2WI before and after enhancement (386.67+/-69.04 vs.492.67+/-112.50,t =-2.456, P=0.026).The liver tissue in the modeled mice also showed significantly decreased enhancement CT values (P < 0.01).Synchrotron radiation X-ray imaging showed that the small vessels in the liver tissues of the modeled mice were significantly increased compared to that in the normal mice (P < 0.01).The MR T2W enhanced signal value (439.67+/-104.80, Pearson's r=0.714, P=0.009) and microvascular relative length (676.53+/-122.75, Pearson's r=0.791, P=0.002) were positive correlated with microvessel density (MVD) (14.50+/-5.95),as shown by detection of labeled vWF.The before and after CT enhancement difference (132.60+/-57.02, Pearson's r=-0.612, P=0.034) was negatively correlated with MVD.

CONCLUSIONs MR,CT and synchrotron radiation X-ray imaging can be used for assessing angiogenesis in liver fibrosis,and the findings from each are correlated with the traditional MVD detection method. The two-dimensional imaging of synchrotron radiation X-ray is more intuitive,and has been confirmed as an effective evaluation method for liver angiogenesis.

Animals ; Disease Models, Animal ; Inflammation ; pathology ; Liver Cirrhosis ; pathology ; Liver Function Tests ; Magnetic Resonance Spectroscopy ; Male ; Mice ; Mice, Inbred C57BL ; Neovascularization, Pathologic ; Synchrotrons ; Tomography, X-Ray Computed

Objective To explore the correlations between intravoxel incoherent motion (IVIM) parameters measured at different time points and histopathological markers in an orthotopic xenograft hepatocellular carcinoma (HCC) nude mice model. Methods A total of 40 HCC orthotopic bearing mouse models were established. When they grew to 21 days, 10 HCC-bearing mice were randomly selected as the baseline group (Group A) by a numeric table method. Then the rest mice were randomly selected on the 28th day, 35th day, and 42nd day of the growth by using the same method, 10 each for B, C, and D groups, respectively. All mice underwent MR IVIM study and apparent diffusion coefficient (ADC), true diffusion coefficient (D), pseudo-diffusion coefficient (D*) and perfusion fraction (f) were measured. After the MRI scanning, the tumors were removed for pathological examination. The necrosis score (NF), tumor size and microvessel density (MVD) were calculated. The IVIM parameters were compared among these 4 groups by Kruskal-Wallis H test and the correlations between these IVIM parameters and histological features were studied with Spearman rank correlation test. Results One tumor in each of C and D groups was excluded because f values of IVIM were close to zero. There were significant differences found in ADC and D among all the 4 groups (P＜0.05). However, no difference was found in D*and f (P＞0.05). Compared with the baseline (group A), ADC decreased significantly at 7 and 14 days, whilst D decreased significantly at 7 days. The differences in tumor size, MVD and NF between the 4 groups were statistically significant. Compared with the baseline, the tumor size and NF significantly increased at 7, 14 and 21 days, and MVD increased at 14 and 21 days. Significantly positive correlations were demonstrated between ADC and MVD, NF (r=0.461 and 0.442, P＜0.05), between D and MVD, NF (r=0.568 and 0.519, P＜0.05) after exclusion of the data from the baseline. The parameter f from all the time points including the baseline was positively correlated with histological MVD and NF (r=0.590 and 0.458, P＜0.05). Conclusion IVIM parameters may reflect the intratumoral vascularity, tumor cell proliferation and necrosis of HCC, and they are correlated with the pathological indicators.

Objective To investigate the effect of intravenous ultrafine superparamagnetic iron oxide nanoparticles feraheme (generic name:ferumoxytol) on cerebral infarction volume and inflammatory response in mice with permanent middle cerebral artery occlusion.Methods Thirty C57BL/6J mice were divided into sham operation group,saline control group,and feraheme group by the random number table (n =10 in each group).A permanent right middle cerebral artery occlusion model was induced by the modified suture method in the saline control group and the feraheme group,and no suture was inserted into the mice of the sham operation group.The intervention was performed by tail vein injection at 24 h after modeling.The sham operation group and the feraheme group were injected with 18 mg/kg feraheme,and the saline control group was injected with the same volume of normal saline.The neurobehavioral scores were conducted at 24 h (before the feraheme or saline injection) and 48 h (before the MRI exam) after modeling.MRI scans were performed at 48 h after modeling,and the cerebral infarction volume was calculated according to T2-weighted imaging.After the end of the scan,orbital blood was collected for the detection of serum tumor necrosis factor (TNF)-α,interleukin (IL)-1 β,and IL-6 levels.Then,the mice were sacrificed and the brain tissue was taken for HE staining and Ibal immunohistochemical staining.Results There were no significant differences in the infarct volume and neurological function score between the saline control group and the feraheme group.The serum levels of TNF-α,IL-1β,and IL-6 in the saline control group and the feraheme group were significantly higher than those in the sham operation group (P ＜0.05),but there was no significant difference between the saline control group and the feraheme group.Conclusion Intravenous injection of 18 mg/kg feraheme at 24 h after cerebral ischemia did not affect the infarct volume and inflammatory response,suggesting that this dose of feraheme can be used for molecular imaging studies of inflammatory response after cerebral ischemia.