The value of gadoxetate disodium enhanced MRI in the quantitative assessment of liver fibrosis / 中华放射学杂志

Objective:To evaluate the value of quantitative analysis of the relative signal intensity (SI) of liver gadolinium disodium enhanced MRI in the grading of liver fibrosis.Methods:From January 2018 to October 2020, the relevant data of 131 patients who underwent gadoxetate disodium enhanced MRI examination were retrospectively analyzed in Henan Provincial People′s Hospital. All patients had histopathological results. According to the Laennec grading system of liver fibrosis, the patients were classified in F0-F1 (27 cases), F2 (19 cases), F3 (17 cases) and F4 (68 cases). The signal intensity of the liver, erector spinae and spleen were measured before and after the enhancement; and 5 post-contrast relative SI parameters were calculated, including the relative enhancement (RE), liver-to-muscle contrast ratio (LMC), liver-to-spleen contrast ratio (LSC), LMC increase rate, LSC increase rate. The differences of 5 post-contrast relative SI parameters among the different fibrosis grades were compared using one-way analysis of variance. The receiver operating characteristic (ROC) curves were drawn to evaluate the diagnostic efficacy of 5 post-contrast relative SI parameters in the diagnosis of clinically significant liver fibrosis (F2-F4), advanced liver fibrosis (F3-F4) and liver cirrhosis (F4).Results:The differences of RE, LMC, LSC, LMC increase rate, LSC increase rate among different liver fibrosis grades were statistically significant (all P<0.001). With the increasing of the degree of liver fibrosis, the RE, LMC increase rate and LSC increase rate showed decreased. ROC results showed that the area under the curve (AUC) of RE, LMC increase rate, LSC increase rate in diagnosing liver fibrosis in all levels were greater than those of LMC and LSC. The AUC values of RE, LMC increase rate, LSC increase rate in the diagnosis of significant fibrosis (F2-F4) were 0.89, 0.86, 0.83, with the sensitivity as 81.7%, 71.2%, 81.7%, and the specificity as 96.3%, 85.2%, and 74.1%, respectively. The AUC values of RE, LMC increase rate, LSC increase rate in the diagnosis of advanced liver fibrosis (F3-F4) were 0.93, 0.88, 0.86, with the sensitivity as 84.7%, 72.9%, 91.8%, and the specificity as 91.3%, 87.0 %, 71.7%; and the AUC values for diagnosing liver cirrhosis (F4) were 0.92, 0.86, 0.85, with the sensitivity as 82.4%, 76.5%, 92.7%, and the specificity as 88.9%, 81.0%, 65.1%, respectively. Conclusion:Gadoxetate disodium enhanced MRI relative SI parameters including RE, LMC increase rate and LSC increase rate might be used as a useful imaging marker in liver fibrosis grading.

The value of circulating miR-143 level in predicting early response to concurrent chemoradiotherapy in cervical cancer patients / 中华放射肿瘤学杂志

Objective:To investigate the value of serum miR-143 level combined with MRI in predicting the early response to concurrent chemoradiotherapy (CCRT) in cervical cancer.Methods:A total of 85 patients with pathologically confirmed cervical cancer underwent conventional MRI, intravoxel incoherent motion diffusion-weighted imaging (IVIM-DWI), and dynamic contrast-enhanced MRI (DCE-MRI) before CCRT. The biopsy tissues and serum samples were collected. The differential expression of miRNA in the biopsy tissues was determined by microarray chip. The expression level of miR-143 in the serum samples was analyzed by qRT-PCR. All patients were divided into the non-residual and residual tumor groups according to post-treatment MRI. Pre-treatment clinical factors, MRI parameters and miR-143 between two groups were statistically analyzed by the univariate and multivariate analyses. The optimal thresholds and predictive performance for post-treatment incidence of residual tumors were estimated by drawing the ROC curve.Results:At one month after CCRT, there were 52 patients in the non-residual tumor group and 33 patients in the residual tumor group. In the residual tumor group, pre-treatment FIGO staging, apparent diffusion coefficient (ADC), D and V e were significantly higher (all P<0.05), whereas K trans value was significantly lower ( P<0.001) when compared to those in the non-residual tumor group. The miRNA array analysis showed that there were 16 miRNAs with differential expression levels between two groups (all P<0.05). Among them, the increase of miR-143 was the most significant in the residual tumor group. Compared with the residual tumor group, the expression level of serum miR-143 was significantly down-regulated in the non-residual tumor group ( P=0.002). Compared with the SiHa cells, the expression level of miR-143 in the SiHa-R cells was significantly up-regulated ( P<0.05). Multivariate analysis showed that only miR-143, D, K trans and V e were the independent prognostic factors. The combination of multi-parametric MRI and miR-143 exhibited the highest predictive performance (AUC=0.975), with a sensitivity of 84.8% and a specificity of 96.2%. Conclusion:The combination of multi-parametric MRI with miR-143 further improves the predictive performance for residual tumors after CCRT, which contributes to the personalized treatment of cervical cancer.

Evaluation of the major features of liver imaging reporting and data system using Gd-EOB-DTPA enhanced MRI based on subtraction technique / 中华放射学杂志

Objective:To explore the incremental value of subtraction technique in evaluating the major features of liver reporting and data system version 2018 (LI-RADS v2018) on gadolinium-ethoxybenzyl-diethylenetriamine pentaacetic acid (Gd-EOB-DTPA) enhanced MRI.Methods:The Gd-EOB-DTPA enhanced MRI of 117 pathologically verified hepatocellualr carcinoma(HCC) from 87 high-risk patients in Henan Provincial People′s Hospital from January 2019 to July 2020 was analyzed retrospectively. The major features of LI-RADS in arterial phase, portal venous phase, subtraction and combined images were evaluated including nonrim arterial phase hyperenhancement (Nonrim APHE), nonperipheral washout and enhancing capsule. The lesions were graded according to LI-RADS v2018. According to the lesion size (<20 mm, ≥20 mm) and T 1WI signal intensity (hypointensity, isointensity or hyperintensity), the patients were divided into different subgroups. Cochran′s Q test was used for the comparison of the detection rate of the major features of LI-RADS and the accurate diagnosis rate based on LR-5 as the diagnostic standard among multiple groups. McNemar test was used for the comparison between two groups. Results:For all HCC, hypointensity HCC and HCC ≥20 mm, the detection rate of Nonrim APHE (χ2=12.190, 12.500, 10.083, all P<0.001) and the accurate diagnosis rate of HCC (χ2=14.450, 12.500, 10.083, all P<0.001) of subtraction images from arterial phase were significantly higher than that of arterial images. For HCC<20 mm, the detection rate of Nonrim APHE combined with arterial phase images was significantly higher than that in arterial phase images (χ2=5.143, P=0.016). For all HCC and isointensity or hyperintensity HCC, the detection rate of nonperipheral washout combined with portal venous phase images was higher than that in portal venous phase images (χ2=7.111, 6.125, P=0.004, 0.008). The detection rate of enhancing capsule of subtraction images from portal venous phase was higher than that of portal venous phase images in all groups (all P<0.017). The accurate diagnosis rate of subtraction images from portal venous phase in all HCC and HCC≥20 mm was higher than that in portal venous phase images (χ2=6.722, 6.750, P=0.008, 0.006). The accurate diagnosis rate of LR-5 in all groups using subtraction images from arterial phase and portal venous phase was higher than that of MRI images (all P<0.013). Conclusion:For Gd-EOB-DTPA dynamic enhanced MRI, subtraction images from arterial phase and portal venous phase are better than arterial phase and portal venous phase images in displaying Nonrim APHE, nonperipheral washout and enhancing capsule, which can improve the LI-RADS classification of HCC.

Correlation of quantitative parameters from dynamic contrast-enhanced MRI with pathological grades of esophageal squamous cell carcinoma / 中华放射学杂志

Objective To investigate the correlation between dynamic contrast enhancement magnetic resonance imaging (DCE-MRI) quantitative parameters and pathological grading in esophageal squamous cell carcinoma(SCC). Methods Prospective analysis of esophageal squamous cell carcinoma confirmed by electronic gastrointestinal endoscopy was performed. Thirty nine patients who underwent radical resection of esophageal carcinoma with MRI examination one weeks before operation were included. All patients underwent routine chest MRI and DCE-MRI scans, and DCE-MRI quantitative parameters including volume transfer constant (Ktrans), exchange rate constant (Kep) and extravascular extracellular volume fraction(Ve)were measured.Pathological analysis of postoperative specimens,including pathological grading(highly differentiated,moderately differentiated,poorly differentiated,undifferentiated),gross tumor pathological type(ulcerative type,medullary type,fungating type,sclerotic type)and local infiltration degree (T staging) were performed. Kruskal-Wallis H test was used to compare the differences of quantitative parameters between different pathological T staging,gross tumor pathological types and pathological grades of DCE-MRI,and a Dunn-Bonferroni test for post hoc comparisons.Spearman rank correlation analysis was used to evaluate the correlation between DCE-MRI parameters and pathological grading of esophageal squamous cell carcinoma.The ROC curves was used to evaluate the efficiency of different parameters in the diagnosis of poorly differentiated esophageal squamous cell carcinoma. Result Among the thirty nine patients, they were divided into three group according to pathological findings: well differentiated (12 patients),moderately differentiated(15 patients)and poorly differentiated group(12 patients);ulcerative type (19 patients), fungating type(10 patients), medullary type(10 patients);T1, 2 stage(16 patients), T3 stage(14 patients), and T4 stage(9 patients). There was no significant difference in the value of Ktrans, Kepand Ve between different T staging groups and different tumor pathological types groups(all P>0.05).The differences of Ktrans, Kepand Vebetween different pathological grading groups were statistically significant (all P<0.05). There were positive correlation between Ktrans, Kep, Veand the pathological grading, rs value were 0.874, 0.672, 0.578 respectively, all P<0.01. The ROC curve area of Ktrans, Kepand Vein the diagnosis of poorly differentiated esophageal squamous cell carcinoma was 0.941,0.809 and 0.773 respectively.The diagnostic efficiency of Ktranswas the best.Conclusions The quantitative parameters of DCE-MRI are correlated with the pathological grading of esophageal squamous cell carcinoma. Ktrans, Kepand Vecan reflect the perfusion characteristics of esophageal squamous cell carcinoma.

Evaluation of hepatic fibrosis in chronic hepatitis B with parameters obtained from multi-models of diffusion-weighted MRI / 中华放射学杂志

Objective To explore the value of various diffusion parameters obtained from monoexponential, biexponential and stretched exponential diffusion-weighted imaging models in assessing hepatic fibrosis in chronic hepatitis B(CHB). Methods A total of 52 patients who were diagnosed hepatitis B by the markers of hepatitis and were confirmed by liver biopsy pathology were prospectively recruited between June 2014 and May 2016 in People's Hospital of Henan Province. Concomitantly, 30 healthy volunteers who had no history of hepatitis B and liver dysfunction were enrolled in the control group. All patients underwent multi-b values DWI on a 3.0 T MRI unit. ADC was calculated by using the monoexponential model. True diffusion coefficient(Dt),pseudo diffusion coefficient(Dp)and fraction of perfusion(f)were calculated by using the biexponential model.Distributed diffusion coefficient(DDC)and water molecular diffusion heterogeneity index(α)were calculated by using the stretched exponential model. Liver biopsy specimens were staged according to the degree of hepatic fibrosis (S0 to S4). The Kruskal-Wallis test was employed for the comparison of each parameter among the control group and the fibrosis stage groups. The Mann-Whitney U test was adopted to compare each parameter between fibrosis stage≤S1and≥S2,between≤S2 and≥S3.Spearman rank correlation coefficients were obtained to assess the correlation of the parameters with the fibrosis stages.ROC analysis was used to evaluate the performance of various parameters in predicting stage≥S2 and≥S3.Results The hepatic fibrosis stage distributions were as follows:1 cases with S0,9 cases with S1,22 cases with S2,11 cases with S3,9 cases with S4.ADC,Dt,f and DDC values all showed significant difference among the control group and groups S1,S2,S3,S4(all P<0.05), while Dp and α values showed no significant difference(P>0.05). Dt, DDC and ADC showed a moderate negative correlation with the fibrosis stage(r=-0.630,-0.603 and-0.464,respectively,all P<0.01),and f showed a mild negative correlation with the fibrosis stage(r=-0.379,P<0.05),while Dp and α values showed no correlation with the fibrosis stages(all P>0.05).The ADC, Dt, f and DDC values all showed significant difference between stage≥S2 and≤S1,between stage≥S3 and≤S2(all P<0.05),and the parameter values of the former were greater than those of the latter. While Dp and α values showed no significant difference among both groups(all P>0.05).The AUCs of ADC,Dt,f and DDC values for detecting fibrosis stage ≥S2 were 0.738,0.835,0.740 and 0.831, and the AUCs of ADC, Dt, f and DDC values for detecting fibrosis stage≥S3 were 0.716, 0.811, 0.672 and 0.798. Conclusion The Dt derived from biexponential and DDC derived from stretched exponential DWI could be useful for the staging of hepatic fibrosis in CHB.

High-resolution 3.0 T MR imaging of esophageal carcinoma with histopathological findings / 中华放射学杂志

Objective To prospectively determine the feasibility of high-resolution in vivo MR imaging in the evaluation of esophageal carcinoma invasion at 3.0 T.Methods One hundred and eighteen patients with esophageal carcinoma,proven by the gastroscopic biopsy,were prospectively studied using 3.0 T MR.The esophageal specimens were sectioned transversely to keep consistent in the orientation with the MR images,the histopathological stage was made and the thickness of the tumor on the largest diameter of the slice were measured.The MR images were reviewed in the transverse plane.According to the seventh American joint committee on cancer,the MR stage was made and the tumor's thickness was measured.The MR images and the histopathological slices were matched.The staging diagnostic efficacy of the MR imaging was evaluated with the histopathological results as the standard reference,Kappa test was used to compare the stage of MR imaging with that at the histopathological analysis.Bland-Altman scatterplots were used to compare the thickness of tumor measured on the MR images with that at the histopathological measurement.Results Ninety seven cases(82.2％,97/118) of MR stage were accurately made,including 7 T1a,15 T1b,18 T2,25 T3 and 32 T4a cases,furthermore,14 cases were over staged and 7 cased were underestimated.The MR stage was highly consistent with the histopathological stage (Kappa=0.772).The sensitivity for the staging of high-resolution MR imaging at 3.0 T was 58.3％(7/12) to 100.0％(32/32),the specificity was 95.3％ (82/86) to 98.1％ (104/106),and the accuracy was 91.5％ (108/118) to 96.6％ (114/118),respectively.Bland-Altman scatterplots demonstrated that the discrepancy of the mean thickness between the value obtained by three radiologists respectively and the histopathological analysis were 2.0,2.6 and 2.1 mm,which demonstrated a good consistency.Conclusion High-resolution MR images obtained at 3.0 T can be used to evaluate the depth of carcinoma invasion and provide excellent diagnostic accuracy for preoperative staging.

Diagnosis of testicular germ cell tumors with magnetic resonance imaging / 实用放射学杂志

Objective To explore the imaging characteristics of testicular germ cell tumors and to improve the MRI diagnostic level. Methods MRI and clinical data of 25 cases confirmed testicular germ cell tumor by pathological examination were retrospectively analyzed. All the 25 cases were performed plain scan of MRI,and 16 patients underwent MRI enhanced scan.The size,morphology,signal intensity, adjacent structures,enhancement figure and tumor supplying artery were assessed and the histopathological findings were servered as the standard of reference.Results In the all 25 testicular germ cell tumors,10 cases were seminoma,8 cases showed homogeneous low signal intensity,2 cases of seminoma were low signal intensity on T2 WI,furthermore 5 cases performed poor nodular enhance-ment,2 cases performed homogeneous enhancement,4 cases performed fibrous septa enhancement.4 cases were yolk sac tumor ap-peared equal-low signal on T1 WI,slightly high signal intensity on T2 WI and progressive enhancement.Mature teratoma,pidermoid cyst and mixed germ cell tumor were 3 cases respectively,the MRI demonstrated mixed low signal intensity on T1 WI and mixed high signal on T2 WI.2 cases were embryonal carcinoma demonstrated middle-low signal intensity on T1 WI,and mixed low signal intensity on T2 WI.The two cases revealed bleeding signal intensity and septa enhancement.Conclusion MRI can be used to diagnose germ cell tumors with high accuracy,and provides essential information for pathological type,stage and differential diagnosis.

Hybrid operation for the treatment of Stanford type B aortic dissection / 介入放射学杂志

Objective To evaluate the clinical effect of hybrid operation in treating Stanford type B aortic dissection. Methods During the period from January 2011 to December 2013, hybrid operation was performed in 33 patients with complex Stanford type B aortic arch dissection. The patients included 28 males and 5 females with a average age of (50±12) years. The clinical effect and the complications, occurring in perioperative period and in 24-month follow-up period, were analyzed. Results The operation was successfully accomplished in all 33 patients, with a technical success rate of 100%. The average hospitali-zation time was 20 days. After the operation, 29 cases were followed up for 3-34 months and 4 cases were lost to follow up, the following-up rate was 87.9%. In 21 cases, the following-up time was over 12 months. Postoperative angiography showed that there was no typeⅠendoleak; complications included pulmonary infection (n=1), strokes (n=1), reversible abnormal renal function (n=6) and retrograde aortic arch dissection (n=1). No paraplegia occurred. During hospitalization time, two cases died, the mortality was 6.06%. During the following-up time, graft infection occurred in one case and continued presence of retrograde aortic arch dissection was observed in one case. Conclusion The complication occurrence after hybrid operation for Stanford type B aortic dissections is low. The hybrid technique is very safe and feasible, but several serious postoperative complications should not be ignored. The long-term effectiveness needs to be further clarified by systemic and large sample studies.

Imaging features of seminomas and nonseminomatous germ cell tumors / 中华放射学杂志

Objective To explore the imaging characteristics of seminomas and nonseminomatous germ cell tumors (NSGCT) and its pathological foundation. Methods CT and MR imaging manifestations in 25 cases of testicular germ cell tumors proved by pathological examinations were analyzed retrospectively. All tumors were divided into seminomas group (12 cases) and NSGCT group (13 cases). In the seminomas group, 5 cases were examined by CT and 4 of those also had contrast enhanced CT. Seven cases had MRI and 4 of those had dynamic enhanced MRI. In the NSGCT group, 5 were examined by plain CT in which two were by contrast enhanced CT, eight were by MRI in which 4 were by dynamic enhanced MRI. CT or MRI characteristics (morphology, density or intensity, enhancement) in both groups were analyzed by Fisher test. Results Histological examination revealed 25 intratesticular lesions. In 12 seminomas, 10 showed a nodular/lobulated shape, 5 showed a mixed density or intensity. In 13 NSGCT, only one lesion showed a lobular shape, 11 showed a mixed density or intensity. Seven seminomas showed a low signal on T2WI on MRI while only two NSGCT showed this sign. In four lesions underwent dynamic MRI scanning, 3 showed fibrous septum enhancement while no lesions in NSGCT showed this sign. The occurrence rate of the above imaging characteristics in both group was significantly different (P<0.05). Conclusion Seminomas and NSGCT may have their own CT and MRI characteristics, which may be of great value for differential diagnosis .

The study of improving imaging quality of CT on Budd-Chiari syndrome with optimal monochromatic technology of single-source dual-energy CT / 实用放射学杂志

Objective To investigate the effect of special CT monochromatic images on improving imaging quality in Budd-Chiari Syndrome.Methods 40 patients with Budd-Chiari Syndrome underwent CT venography (CTV)with gemstone spectral imaging (GSI).Using the optimal contrast to noise ratio (CNR)curve of GSI software,the optimal CNR monochromatic images of the infe-rior vena cava and hepatic vein were chosen.The CT value of the intrahepatic segment of inferior vena cava,hepatic vein and the same level liver tissue were measured,and the CT value of the same region were measured on 140 kVp mixed energy images and 70 keV images.CNR on the optimal monochromatic images,the 140 kVp mixed energy images and 70 keV images were calculated respectively,and the image quality of the optimal monochromatic image,the 140 kVp mixed energy images and 70 keV images were subjective scoring.One-way ANOVA was used for statistical analysis using SPSS1 7.0 software.Results The optimal keVs from monochromatic images were distributed at 40 keV (50%)and (5 1 ± 1 )keV (50%)for IVC and 40keV (25%)and (53 ± 3)keV (75%)for HV.The CNR and CT value and subjective score of IVC/HV got from the optimal monochromatic images were signifi-cantly higher than those from 140 kVp mixed energy images and 70 keV images respectively(P <0.01 ).Conclusion The optimal monochromatic images provide higher image quality of IVC and HV in patientswithBudd-Chiari syndrome.

Initial study of biexponential model of intravoxel incoherent motion magnetic resonance imaging in evaluation of the liver fibrosis / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>The diagnosis of liver fibrosis is a difficult task at any time using conventional clinical imaging. Intravoxel incoherent motion (IVIM) can be used to investigate both diffusion and perfusion changes in tissues. This study was designed to determine the value of IVIM in the diagnosis and staging of liver fibrosis.</p><p><b>METHODS</b>IVIM examinations were performed on a GE 3.0T MR scanner in 25 patients with liver fibrosis and 25 healthy volunteers as the control group. Patients with liver fibrosis diagnosis were confirmed by pathology and staged on a scale of F0-4. The standard ADC values and the values of a biexponential model (slow ADC (Dslow), fast ADC (Dfast) and fraction of fast ADC (FF)) were measured in three liver regions per person. The mean standard ADC values, Dslow values, Dfast values and FF values from the study group were compared among the right posterior hepatic lobe, right anterior hepatic lobe and medial segment of the left lobe. Receiver Operating Characteristic (ROC) curves and independent-samples t-tests were used to calculate the mean standard ADC values, Dslow values, Dfast values and FF values from the study group and the control group. Spearman rho correlation analysis was used for the stage of liver fibrosis. The liver fibrosis stages between the groups F0-1 and F2-4, the groups F0-2 and F3-4 were compared.</p><p><b>RESULTS</b>Among the liver fibrosis, there was no significant difference in the mean standard ADC values, Dslow values, Dfast values, and FF values obtained from the right posterior hepatic lobe, right anterior hepatic lobe and medial segment of the left lobe. Using ROC analysis, the Area Under the Curve (AUC) values of standard ADC, Dslow, Dfast, FF were all between 0.7 to 0.9. The mean standard ADC values, Dslow values, Dfast values and FF values of the liver in the study group were significantly lower than the values in the control group (P < 0.05). As the stage of the fibrosis increased, the values decreased by Spearman rho correlation analysis. The mean values (standard ADC, Dslow, Dfast, and FF) of liver fibrosis stages between the groups F0-1 and F2-4, the groups F0-2 and F3-4 showed significant differences (P < 0.05).</p><p><b>CONCLUSIONS</b>IVIM can reflect the conditions of perfusion and diffusion in liver fibrosis and thus distinguish between normal liver and liver fibrosis. The IVIM technique may serve as a valuable tool for detecting and characterizing liver fibrosis, and monitoring its progression in a noninvasive manner.</p>

Radioresistance change and the mechanism of human esophaged cancer EC9706 cells in hypoxia / 中华放射医学与防护杂志

Objective To investigate the expression of hypoxia-inducible factor-1 alpha (HIF-1 α),vascular endothelial growth factor-A (VEGF-A) and vascular endothelial growth factor-D (VEGF-D)in hypoxic environment as well as the relationship between HIF-lα and VEGF-D.Methods Human esophageal cancer cell line EC9706 was cultured under hypoxia environment for 6,12 and 24 h,the cell radiosensitivity was evaluated by survival curve.HIF-1 α siRNA was constructed and transfected into human EC9706 cells.Protein expressions of HIF-1 α,VEGF-A and VEGF-D were analyzed by Western blot before and after RNA interference.Results EC9706 cells under hypoxia showed radioresistance with a SF2 of 0.62 higher than that of normoxic cells of 0.43.Moreover,the protein expressions of HIF-1α,VEGF-A and VEGF-D were all increased (F =205.24,227.88,130.55,P ＜0.05) due to hypoxia treatment.On the contrary,after HIF-1α siRNA transfer,the protein expressions of HIF-1α,VEGF-A and VEGF-D in EC9706 cells were not influenced by hypoxia treatment.Conclusions EC9706 cells in hypoxic environment was radioresistance,and the upexpressions of HIF1α,VEGF-A and VEGF-D may be involved.

A phantom study of dose reduction potential in pelvic CT with advanced iterative reconstruction algorithms / 中华放射医学与防护杂志

Objective To assess the dose reduction potential of adaptive statistical iterative reconstruction(ASiR)and model-based iterative reconstruction(MBIR)in pelvic CT with a standard male phantom.Methods A Fluke Biomedical RANDO standard male phantom was scanned with discovery CT750 HD using different tube currents.CT images were reconstructed with FBP,50％ASiR and MBIR.The CT value,the image noise and the contrast-to-noise ratio(CNR)for the sacral vertebra relative to muscle were measured.The volume CT dose indexes(CTDIvo1)and dose-length product(DLP)were recorded.Results Compared with FBP,using 50％ASiR and MBIR had significant reduced image noise and greater CNR.The effective minimal tube currents for displaying sacral vertebra were 250 mA(FBP),180 mA(50％ASiR),and 100 mA(MBIR).With the similar image quality using FBP,the dose was reduced by 28.0％ and 59.9％ using 50％ASiR and MBIR,respectively.Conclusions Using advanced iterative algorithms can reduce image noise,improve CNR,and reduce the radiation dose in pelvic CT examination.

Computed tomography features of gastrointestinal stromal tumor / 中华消化外科杂志

Gastrointestinal stromal tumors (GISTs) are common mesenchymal neoplasms in the gastrointestinal tract.The results of computed tomography play important roles in the diagnosis,treatment planning and follow up of GISTs. From August 2007 to January 2012,28 patients with GISTs were admitted to the Henan Provincial People's Hospital. Sixteen tumors showed extra-luminal growth,4 showed intra-luminal growth,7 involved both intra- and extra-luminal growth,and 1 showed extra-gastrointestinal growth.After administration of contrast media,9 tumors demonstrated homogeneous enhancement,18 showed heterogeneous enhancement and 1 showed non-obvious enhancement.The enhancement of tumors in arterial and venous phase was 20 Hu higher than that in plain scan.Angiogenesis was displayed in 6 tumors,and feeding arteries were observed in 3 tumors.

Clinical application of multi-slice helical CT volumetric scanning in lumber spine / 中华放射学杂志

Objective To evaluate the clinical application value of multi-slice helical CT volumetric (VH) scanning in lumber spine. Methods One thousand of patients with back and leg pain who underwent CT examinations were selected as subjects. We simulated the traditional protocol of single-slice(SS) discrete scanning for L3/4, L4/5, and LS/S1 intervertebral discs. The VH scanning mode was performed with 120 kV, 210 mAs,pitch of 1.5 and coverage of 97. 5 mm. The simulated SS scanning mode was performed with 120 kV, 240 mAs and coverage of 45.0 mm. The diagnostic outcomes and the radiation doses were compared between the two scanning modes. Two groups doctors observed ten terms, including the osseous spinal stenosis,narrowed intervertebral space and so on in two scanning modes respectively. Then consistency analysis of the data was carried out. Results The VH scanning mode showed far more features than the SS mode. The detection rates of the VH mode in the osseous spinal stenosis, narrowed intervertebral space,herniated nucleus pulposus, narrowed lateral recess, vertebral lesion, hypertrophy of L5 transverse process,abnormal direction of facet, facet degeneration, lumbar spondyloschisis, and paraspinal soft tissue were 11.8% (n =118), 38. 5% (n =385), 9. 3% (n =93), 46. 8% (n =468), 31.4% (n =314), 5.7% (n =57), 25.4% (n = 254), 49. 7% (n = 497), 9.9% (n = 99), and 0. 6% (n = 6) respectively, while the detection rates of the SS mode in ten terms were 5.6% (n = 56), 0, 0. 6% (n = 6), 27. 9% (n = 279),22.4% (n =224), 1.2% (n = 12), 16.7% (n = 167), 37.2% (n =372), 0.5% (n =5), and 0.2%(n = 2) respectively. The difference between the two groups had statistically significance (average P <0.05), except the paraspinal soft tissue abnormal (P > 0.05). The detection rates of the VH mode were higher than the SS mode in the osseous spinal stenosis, narrowed intervertebral space, herniated nucleus pulposus, lumbar spondyloschisis, being 6.2% (n = 62) , 38. 5% (n = 385) , 8.7% (n = 87), and 9.4%(n =94), respectively. In addition, VH mode only partially showed the articular facets, narrowed lateral recess, hypertrophy of L.5 transverse process, and paraspinal soft tissue. We could not acquire the imaging slices paralleling to intervertebral discs in SS mode in 467 patients (46.7%) with lumbosacral angle greater than 35°. The radiation dose of VH mode (164.9 mGy/em) was slightly higher than SS mode (147.0 mGy/cm) Conclusion MSCT VH scanning mode can significantly improve the diagnostic rate of lumbar spine diseases compared with SS mode, and was not restricted by the lumbosacral angle with slightly increasing radiation dosage.

CT Diagnosis of Osteogenic Benign Tumor and Tumor Mimics in Orbit / 实用放射学杂志

Objective To analyze the CT features of orbital bone benign tumor and tumor mimics,so that to improve the diagnostic accuracy of these diseases.Methods CT appearances of orbital bone benign tumor and tumor-like lesion in 32cases proved by surgery,pathology and clinical features were reviewed.The lesions included orbital bone benign tumor(n=17)and tumor-like lesions(n=15).Results On CT,orbital osteomas in 9 cases showed homogeneous high density and cavernous bone-like density or ground glass-like density;ossifying fibroma in 5 cases were well-defined expansion of bone with ossification,cystic areas within the lesions;epidermal cyst in 2 displayed cystic density ;calcification and ossification could be seen in 1 case of chondroma ;10 cases of fibrous dysplasia showed ground glass-like density with cystic areas in poor-defined expansion of bone;the osteolytic destruction with well-defined margin were founded in 3 cases of orbital Langerhans' cell histiocytosis;1 case of aneurismal bone cyst appeared as cystic and expansive lesion with thin bone shell;1 case of osteopetrosis showed homogeneous high density in orbital wall.Conclusion Various orbital bone benign tumor and tumor-like lesions have different CT features.CT scan can clearly demonstrate the extent,density,border and the relationship with adjacent tissue of these lesions.

A Experimental Study of Growth-plate of Developmental Long Bones:MRI,Anatomy and Histology / 实用放射学杂志

Objective To describe the MR appearancses of growth-plate of the developmental long bones,and to study the correlativity of MRI with the anatomy and histology findings.Methods 40 pigs with normal knees were examined by 1.0 T scanning system with various orientations and sequences,MR imagings were compared with the results of sectional anatomy and histology.Results According to MRI,we divided the evolution of growth plate into four developmental stages;the earlier forming stage of growth plate(aged the 80～95 days of pregnancy),the forming stage(aged the 95 days of pregnancy-2 months),the maintaining stage (aged 2 months-3.5 years),the closing stage(aged 3.5～4.5 years).The MRI manifestations of growth plate of knees reflected the findings of sectional anatomy perfectly and histology to a certain extent in each developmental stage.Conclusion MRI is very useful and helpful in dividing the developmental stages of growth-plate,guessing the foundation of anatomy and histology,diagnosing and differentiating all kinds of growth plate lesions.