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find Author "袁放" 14 results
  • Methods and Applications for Quantitative Measurement of Iron in Human

    Objective To summarize the methods and applications for quantitative measurement of iron in human.Methods The methods and applications for quantitative measurement of iron in human were analyzed retrospectively via reviewing the literatures domesticly and abroad, and summarized the advantages and disadvantages respectively. Results The methods for quantitative measurement of iron included laboratory tests, pathology examinations, CT, superconducting quantum interference device investigation (SQUID), and MRI. Conclusions Laboratory test is the most simple and economic method for quantitative measurement of iron in human. Percutaneous liver biopsy is the gold standardmethod. Radiologic examinations, especially MRI, may be main methods of measuring liver iron content in future.

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  • Comparative Study of Quantitative Diagnosis of Hepatic Fat Content by MRI and Patholgy

    ObjectiveTo investigate the diagnostic value of spectral saturation inversion recovery, gradient-echo chemical shift MRI, and proton magnetic resonance spectroscopy in quantifying hepatic fat content. MethodsConventional T1-weighted and T2-weighted scanning (without fat saturation and with fat saturation), gradient-echo T1W in-phase (IP) and opposedphase (OP) images and 1H-MRS were performed in 31 healthy volunteers and 22 patients who were candidates for liver surgery. Signal intensities of T1WI amp; T1WIFS (SInonfat1, SIfat1), T2WI amp; T2WI-FS (SInonfat2, SIfat2), and IP amp; OP (SIin, SIout) were measured respectively, the relative signal intensity one (RSI1), relative signal intensity two (RSI2), and fat index (FI) were calculated. Peak values and the area under peak of 1H-MRS were measured, and the relative lipid content of liver cells (RLC ) were calculated. Twenty-two patients accepted liver resection and histological examination after MRI scanning, the proportion of fatty degenerative cells were calculated by image analysis software. Results①Hepatic steatosis group showed higher average values of RSI1, FI, and RLC to non-hepatic steatosis group (Plt;0.05), while there was no significant difference in RSI2 between two groups (Pgt;0.05). ②There was a statistical significant difference in RLC among different histopathological grades of hepatic steatosis, and RLC increased in parallel with histopathological grade (Plt;0.05).There was no significant difference in RSI2, RSI1, and FI among different histopathological grades, although the latter two had a tendency of increasing concomitant with histopathological grade (Pgt;0.05). ③The values of FI and RLC were positively correlated with the PFDC (r=0468, P=0.027; r=0771, Plt;0.000 1), while they were not in RSI1 and RSI2 (r=0.411, P=0.057; r=0.191, P=0.392). ConclusionsSPIR, Gradient-echo chemical shift MRI and 1H-MRS can help to differentiate patients with hepatic steatosis from normal persons, the latter also can help to classify hepatic steatosis. In quantifying hepatic fat content, 1H-MRS is superior to gradient-echo chemical shift MRI, while SPIR’s role is limited.

    Release date:2016-09-08 10:41 Export PDF Favorites Scan
  • Preliminary study on differential diagnosis of liver cancer and hepatic hemangioma by texture analysis of non-enhanced CT images

    Objective To determine feasibility of texture analysis of non-enhanced CT scan for differential diagnosis of liver cancer and hepatic hemangioma. Methods Fifty-six patients with liver cancer or hepatic hemangioma confirmed by pathology were enrolled in this retrospective study. After exclusion of images of 4 patients with artifacts and lesion diameter less than 1.0 cm, images of 52 patients (57 lesions) were available to further analyze. Texture features derived from the gray-level histogram, co-occurrence and run-length matrix, absolute gradient, autoregressive model, and wavelet transform were calculated. Fisher, probability of classification error and average correlation (POE+ACC), and mutual information coefficients (MI) were used to extract 10 optimized texture features. The texture characteristics were analyzed by using linear discriminant analysis (LDA) and nonlinear discriminant analysis (NDA) provided by B11 module in the Mazda software, the minimum error probability of differential diagnosis of liver cancer and hepatic hemangioma was calculated. Most discriminating features (MDF) of LDA was applied to K nearest neighbor classification (KNN); NDA to extract the data used in artificial neural network (ANN) for differential diagnosis. Results The NDA/ANN-POE+ACC was the best for identifying liver cancer and hepatic hemangioma, and the minimum error probability was the lowest as compared with the LDA/KNN-Fisher, LDA/KNN-POE+ACC, LDA/KNN-MI, NDA/ANN-Fisher, and NDA/ANN-MI respectively, the differences were statistically significant (χ2=4.56, 4.26, 3.14, 3.14, 3.33;P=0.020, 0.018, 0.026, 0.026, 0.022). Conclusions The minimum error probability is low for different texture feature selection methods and different analysis methods of Mazda texture analysis software in identifying liver cancer and hepatic hemangioma, and NDA/ANN-POE+ACC method is best. So it is feasible to use texture analysis of non-enhanced CT images to identify liver cancer and hepatic hemangioma.

    Release date:2017-02-20 06:43 Export PDF Favorites Scan
  • The research progress of magnetic resonance quantitative technique in the iron overload of the abdominal parenchyma organ

    Objective To summarize the research progress of magnetic resonance quantitative technique in the iron overload of the abdominal parenchyma organ. Methods By reviewing the related literatures domesticly and abroad, the present status and progress of abdominal magnetic resonance quantitative technique and other examinations in the study of iron overload were analyzed. Results MRI multi-sequence examination technique had changed the research model of iron overload in different organs, and had important clinical significance in imaging diagnosis of abdominal parenchyma organ damage. so far, many techniques of MRI had been used in detection of iron overload, which included signal intensity measurements(including signal intensity ratio and signal intensity difference of positive and negative phases), T2/R2 measurements, T2*/R2* measurements, Dixon and its derivatization, ultrashort echo time technique and susceptibility weighted imaging (including conventional susceptibility weighted imaging and quantitative magnetic sensitive imaging). Conclusion Magnetic resonance quantitative examination technique is expected to be the first choice for detection of hepatic iron overload, and can improve the early detection rate of iron overload pancreatic damage.

    Release date:2017-09-18 04:11 Export PDF Favorites Scan
  • 肝癌的影像学研究进展及其在多学科诊疗中的应用

    Release date:2021-04-25 05:33 Export PDF Favorites Scan
  • Case analysis: Imaging findings of gastric hepatoid adenocarcinoma diagnosed with elevated serum alpha-fetoprotein

    Hepatoid adenocarcinoma is a rare extrahepatic malignant tumor with pathological characteristics similar to hepatocellular carcinoma. It is more common in the gastrointestinal tract and patients often have a history of hepatitis and elevated serum alpha fetoprotein (AFP). In clinical practice, patients may seek medical treatment due to liver lesions or elevated AFP, while primary gastrointestinal lesions are easily ignored. The author presents imaging findings of two patients who were diagnosed with hepatoid adenocarcinoma of stomach (HAS) due to elevated AFP in our hospital. By summarizing their clinical imaging characteristics and sorting out various clinical conditions that may cause elevated serum AFP, in order to improve the recognition and differential diagnosis of HAS.

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  • Imaging Manifestations of Idiopathic Hepatic Arteriovenous Malformation

    Objective To investigate the imaging features of idiopathic hepatic arteriovenous malformation(IHAVM) on multi-detector row spiral CT (MDCT) and magnetic resonance imaging (MRI). Methods Nineteen patients with IHAVM between January 2009 and June 2010 were included for retrospective analysis of the imaging findings on MDCT (n=9) and MRI (n=10), especially the imaging features of IHAVM on contrast-enhanced dynamic scans. Results All IHAVM lesions in 9 patients were isodense in plain scan of MDCT, and showed marked small nodular or linear enhancement with similar intensity to vascular enhancement in arterial phase, and the enhancement continued to persist to portal phase but with reduced enhancement degree. Early visualization of venous tributaries in arterial phase was present in 4 cases, and wedge-shaped or lamellar transient hepatic parenchyma enhancement in arterial phase in the edge of the lesion was observed in 6 cases. In 10 patients with MRI scan, the enhancement patterns of IHAVM were quite similar to the findings on MDCT, with early visualization of venous tributaries in arterial phase in 5 cases and wedge-shaped transient hepatic parenchyma enhancement in arterial phase in the edge of the IHAVM lesion in 7 cases. Conclusion Contrast-enhanced multi-phase MDCT and MRI scans can depict the morphologic and hemodynamic characteristics of IHAVM, thus they are very valuable for the diagnosis of IHAVM.

    Release date:2016-09-08 10:50 Export PDF Favorites Scan
  • Diagnostic Value of 64 Slice Spiral Computed Tomography for Budd-Chiari Syndrome

    Objective To investigate the imaging features of Budd-Chiari syndrome (BCS) on 64 slice spiral computed tomography (64SCT) and the diagnostic value of 64SCT for BCS. Methods Twenty-nine patients diagnosed as BCS by 64SCT were retrospectively included into this study and all the patients were researched by digital substraction angiography (DSA). Two abdominal radiologists analyzed the CT imaging features of BCS, paying attention to the vascular lesion, the morphology abnormality of the liver and the degree of portal hypertension, with review of DSA findings. Results ①The accuracy of 64SCT for BCS was 93.1% (27/29), and there were 2 false positive cases and no false negative case. The accuracy of 64SCT for those patients with thrombosis of inferior vena cava (IVC) and (or) hepatic vein (HV) was high as compared to those with stenosis of IVC and (or) HV. ②The morphology abnormality of the liver included hepatomegaly (24 cases), low attenuation (27 cases) and inhomogeneous pattern of parenchymal contrast enhancement (5 patients in arterial phase and 19 patients in portal vein phase). ③The images of all the patients showed the features of portal hypertension. Conclusion The accuracy of 64SCT for BCS is satisfactory and the false negative is seldom. The 64SCT could accurately display the morphology abnormality of the liver and the compensatory circulation in BCS patients. For those patients with stenosis of IVC and (or) HV, however, the diagnostic power of 64SCT is limited.

    Release date:2016-09-08 11:05 Export PDF Favorites Scan
  • Significance of Apparent Diffusion Coefficient for Pretreatment Prediction of Short-Term Treatment Effect of TACE for Hepatocellular Carcinoma

    ObjectiveTo investigate the significance of apparent diffusion coefficient (ADC value) for pretrea-tment prediction of short-term treatment effect in patients with hepatocellular carcinoma (HCC) who underwent transca-theter arterial chemoembolization (TACE). MethodsA total of twelve HCC patients with twenty-three HCC lesions who underwent TACE in our hospital from May. 2014 to May. 2015 were enrolled prospectively, to explore the difference between pre-and post-TACE in diameter of tumor, ADC value of HCC lesions, ADC value of liver parenchyma, and analyze the predictive significance of ADC value of HCC lesions for TACE in treatment of HCC. ResultsThere were no statistical difference between pre-and post-TACE in diameter of HCC lesions and ADC value of liver parenchyma (P=0.635, P=0.473), but the ADC value of HCC lesions was higher after TACE than pre-TACE (P=0.003). After TACE, the area of necrosis in HCC lesions was≥50% in 17 lesions (73.9%, good effect group), and <50% in 6 lesions (26.1%, poor effect group). Compared with poor effect group, ADC values of HCC lesions in good effect group were both higher before and after TACE (P<0.050). Area under ROC curve (AUC value) of ADC value in HCC lesions before TACE for predicting the effect of TACE was 0.690 (95% CI:0.510-0.879), with the sensitivity and specificity of 82.3% (95% CI:65.5%-93.2%) and 53.8% (95% CI:25.1%-80.8%) respectively, and the demarcation point for good effect and poor effect was 1.24×103 mm2/s. ConclusionThis preliminary study demonstrates that the ADC value of HCC lesions before TACE may be a useful indicator to predict early response of TACE in treatment of HCC.

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  • Quantification of Liver Fat Content by 1H-MR Spectroscopy Imaging at 3.0 T for Therapeutic Evaluation of Fatty LiverPreliminary Study

    ObjectiveTo investigate the feasibility of proton magnetic resonance spectroscopy (1H-MRS) imaging, by which to quantitatively analyze liver fat content for therapeutic evaluation of fatty liver at 3.0 T MRI. MethodsTwenty-six patients who diagnosed with fatty liver were examined with proton MRS at Siemens Trio Tim 3.0 T MRI before treatment and 3, 6 months after treatment, respectively. The water peak, fat peak, water peak area, and fat peak area were detected, and the relative lipid content 1 (RLC1) and relative lipid content 2 (RLC2)were calculated. Fatty liver index (FLI) was referred to the standard which was calculated from triglycerides (TG), gammaglutamyl-transferase (GGT), waist circumference, and body mass index. ResultsThere were significantly different differences of RLC1 and RLC2 among before treatment and 3, 6 months after treatment (Plt;0.05). Compared with before treatment, the RLC1 and RLC2 values significantly decreased on month 3 or 6 after treatment (Plt;0.05). There were positive correlation between RLC1 or RLC2 and FLI (r=0.476, Plt;0.00; r=0.475, Plt;0.001). The intraclass correlation coefficient was more than 0.75 before treatment, the repeatability was better. ConclusionsProton MRS can quantitatively measure liver fat content. It can be reliably used for dynamic monitoring the therapeutic effects for fatty liver. Proton MRS is accurate, and has a good clinical application in dynamically monitoring the progression of fatty liver and evaluating the therapeutic effects of various treatments.

    Release date:2016-09-08 10:45 Export PDF Favorites Scan
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