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Objective To evaluate the diagnostic value of combining 3D arterial spin labeling (3D ASL)and DKI in grading cerebral gliomas. Methods Thirty-four patients with pathologically confirmed gliomas were enrolled in this study.3D ASL and DKI (3 b-values were used:1,1 000,2 000 s/mm2and 15 diffusion directions)were acquired and tumor blood flow (TBF),mean kurtosis(MK),mean diffusivity (MD) and fractional anisotropy of kurtosis (FAk)were measured in the solid part of the tumor.The contralateral normal appearing white matter was used to normalize these parameters.The parameters of 3D ASL and DKI before and after normalization of high-grade and low-grade gliomas were compared.Receiver operating characteristic (ROC)curve analyses were also conducted for all parameters to determine the sensitivity and specificity for grading.Results TBF and MK values were significantly higher in the high-grade gliomas than the low-grade gliomas (All P<0.001),but there were no differences of MD and FAkbetween the two groups.The area under curve (AUC)of combination TBF and MK for glioma grading was 0.951.After normalization,the AUC of combination TBF and MK was 0.986 with a sensitivity of 94.7% and specificity of 94.3%.Conclusion The multi-parameter combined analysis of 3D ASL and DKI further improves the sensitivity and specificity of preoperative glioma grading.
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Objective To investigate use of magnetic resonance diffusion tensor imaging (MR-DTI) for quantitatively evaluating the efficacy of Mailuoning Injection on non-compressive lumbar radiculitis.Methods Nine Bama mini pigs were selected and divided into group A,B and C,3 cases in each group.The non-compressive lumbar radiculitis model was established under CT-guiding.The corresponding therapeutic drugs (group A:10 mL Mailuoning;group B:10 mL normal saline;group C:10 mL diminishing inflammation fluid) were given by epidural injection on 14 d after constructing model.MR-DTI was performed before model construction,14 d after model construction and before treatment.One experimental pig in each group was taken on 3,7,14 d after treatment,performed MR-DTI and killed for taking the nerve root sample to conduct the immunohistochemical detection.The fractional anisotropy (FA) values of nerve root in MR-DTI imaging were measured.The FA values and immunohistochemical detection results were statistically analyzed.Results MR-DTI:the FA values after model construction in each group was decreased (P0.05),but the FA values increase in the group C was earlier and more rapid than other two groups (P0.05),while the FA values had statistical difference between the group B and C (P<0.05).The immunohistochemical results:TNF-α integral absorbency value(IA value) on 7 d after treatment in the group A began to decline;the TNF-α IA value on 14 d after treatment in the group A and C was significantly decreased compared to group B,the difference was statistically significant (P<0.05).Conclusion Mailuoning Injection has a certain effect on non-compressive lumbar radiculitis,which can be evaluated by using DTI.
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Purpose To evaluate the value ofintravoxel incoherent motion (IVIM) imaging in diagnosis of liver fibrosis staging in rats.Materials and Methods Rabbit models of liver fibrosis at different stages were established.All rabbits were divided into four groups based on the pathological results of fibrosis grading as S1-S4.The 1VIM imagings with 8 b-values (0,50,100,200,300,800,1000,1200 s/mm2) were performed.The diffusion coefficient (D),perfusion-related coefficient (D*),and perfusion fraction (f) were calculated and compared between control (only injection of saline) and S 1 group,S2 and S3 group.Results The D value was significantly lower in S1 group compared with control group (P＜0.05),but the D* and f values showed no significant difference between the two groups (both P＞0.05).With the progression of liver fibrosis,the D,D* and f value decreased gradually;the D* value showed significant difference between S2 and S3 group (P＜0.05),but the D and f values showed no significant differences between the two groups (both P＞0.05).Conclusion The D value is useful for differentiation of normal liver and hepatic fibrosis of S1 stage,while the D* is valuable for differentiation of hepatic fibrosis of S2 and S3 stage.However,the f value neither could detect early fibrosis,nor could differentiate hepatic fibrosis staging.IVIM imaging provides a noninvasive method for early and accurate staging of liver fibrosis,which may be of great help in clinical diagnosis and treatment.
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<p><b>BACKGROUND</b>Several previous studies have shown that diffusion-weighted imaging (DWI) can provide additional information for focal pancreatic lesions by demonstrating more restricted diffusion in solid malignant tumors than in chronic pancreatitis, which can be indicated by a decreased apparent diffusion coefficient (ADC). However, these studies have a modest sample size and convey inconclusive results. The aim of this study was to determine, in a meta-analysis, the diagnostic performance of quantitative diffusion-weighted magnetic resonance imaging in distinguishing pancreatic carcinoma from mass-forming chronic pancreatitis.</p><p><b>METHODS</b>We determined the sensitivities and specificities across studies. A summary receiver operator characteristic (sROC) curve was constructed to calculate the area under the curve (AUC).</p><p><b>RESULTS</b>The pooled sensitivity of DWI was 0.86 (95% CI: 0.80-0.91) and the pooled specificity was 0.82 (95% CI: 0.72-0.89). The AUC of the sROC was 0.91 (95% CI: 0.88-0.93).</p><p><b>CONCLUSIONS</b>DWI may be a potentially technically feasible tool for differentiating pancreatic carcinoma from mass-forming chronic pancreatitis. However, large-scale randomized control trials are necessary to assess its clinical value.</p>