Feasibility of improving the quality of children′s abdominal images using split-filter dual-energy CT / 中华放射医学与防护杂志

Objective:To evaluate the effects of split-filter dual-energy CT (SF-DECT) in improving image quality at low doses in the process of abdominal examinations for children.Methods:A preliminary study was conducted using child phantoms. Furthermore, 20 children aged 4-6 years were recruited prospectively for clinical validation from June 2020 to December 2020. Conventional single-energy CT (SECT) and SF-DECT were employed to scan the abdominal areas of the phantoms and children. Then, the CT values, image noise, contrast to noise ratios (CNRs), and image subjective scores of SF-DECT and SECT were compared under various doses (1, 2, 3, and 4 mGy).Results:For the phantoms under doses of 3 and 4 mGy, SF-DECT decreased the image noise by 18.9% and 23.6%, respectively, and increased the liver and kidney CNRs (CNR liv and CNR kid) by 12.8% and 31.9% at most, respectively, compared to SECT ( Z = 3.00, 5.17, P < 0.001). For children, SF-DECT decreased image noise ( Z = 4.64, P < 0.001) and increased CNR liv and CNR kid ( Z = 3.78, 3.39, P < 0.001). For both the phantoms and the children, the subjective scores of images scanned using the SF-DECT were higher than those scanned using the SECT ( Z = 1.96-3.80, P < 0.05). Conclusions:Compared with SECT, SF-DECT can improve the quality of children′s abdominal images. This technique has a certain prospect of optimizing abdominal CT for children. However, it is necessary to conduct in-depth clinical research to verify the result.

A clinical scoring model based on Gd-EOB-DTPA enhanced MRI predicting microvascular invasion in hepatocellular carcinoma: a multicenter study / 中华放射学杂志

Objective:To establish a clinical diagnostic scoring model for preoperative predicting hepatocellular carcinoma (HCC) microvascular invasion (MVI) based on gadolinium-ethoxybenzyl-diethylenetriamine pentacetic acid (Gd-EOB-DTPA) enhanced MRI, and verify its effectiveness.Methods:From January 2014 to December 2020, a total of 251 cases with pathologically confirmed HCC from Tianjin First Central Hospital and Jilin University First Hospital were retrospectively collected to serve as the training set, while 57 HCC patients from Tianjin Medical University Cancer Hospital were recruited as an independent external validation set. The HCC patients were divided into MVI positive and MVI negative groups according to the pathological results. The tumor maximum diameters and apparent diffusion coefficient (ADC) values were measured. On the Gd-EOB-DTPA MRI images, tumor morphology, peritumoral enhancement, peritumoral low intensity (PTLI), capsule, intratumoral artery, intratumoral fat, intratumoral hemorrhage, and intratumoral necrosis were observed. Univariate analysis was performed using the χ 2 test or the independent sample t-test. The independent risk factors associated with MVI were obtained in the training set using a multivariate logistic analysis. Points were assigned to each factor according to the weight value to establish a preoperative score model for predicting MVI. The receiver operating characteristic (ROC) curve was used to determine the score threshold and to verify the efficacy of this scoring model in predicting MVI in the independent external validation set. Results:The training set obtained 98 patients in the MVI positive group and 153 patients in the MVI negative group, while the external validation set obtained 16 patients in the MVI positive group and 41 patients in the MVI negative group. According to logistic analysis, tumor maximum diameter>3.66 cm (OR 3.654, 95%CI 1.902-7.018), hepatobiliary PTLI (OR 9.235, 95%CI 4.833-16.896) and incomplete capsule (OR 6.266, 95%CI 1.993-9.345) were independent risk factors for MVI in HCC, which were assigned scores of 3, 4 and 2, respectively. The total score ranged from 0 to 9. In the external validation set, ROC curve analysis showed that the area under the curve of the scoring model was 0.918 (95%CI 0.815-0.974, P=0.001). When the score>4 was used as the threshold, the accuracy, sensitivity, and specificity of the model in predicting MVI were 84.2%, 81.3%, and 85.4%, respectively. Conclusions:A scoring model based on Gd-EOB-DTPA-enhanced MRI provided a convenient and reliable way to predict MVI preoperatively.

Experimental study on the changes of T1 and T2 values in residual liver of rats after major liver resection and their relationship with liver regeneration process / 中华肝胆外科杂志

Objective:To investigate the changes of T1 and T2 values in residual liver after major liver resection in rats and the relationship with pathologic indices related to liver regeneration.Methods:Seventy healthy male Sprague Dawley rats, SPF grade, aged 7-8 weeks, weighting 250-280 g, were divided into MR scan group ( n=14) and pathologic analysis group ( n=56). The MR scan group was further divided into partial hepatectomy group ( n=7) and the sham operation group ( n=7). MRI T 1 mapping and T 2 mapping were performed before surgery and on day 1, 2, 3, 5, 7, 14, 21 after surgery. T1 and T2 values of liver parenchyma were measured. In the pathologic analysis group, 7 rats were randomly included at each time point before and after surgery for pathologic examination, the diameter and proliferative activity (Ki-67 indices) of hepatocytes were assessed. The changes of imaging and pathologic indices were observed, and the correlations between MR parameters and liver volume and pathologic indices were analyzed. Results:Both T1 and T2 values in liver parenchyma were increased on day 1 after surgery and reached their maximum values on day 2 ( P=0.005 and P<0.001, compared with baseline), then were gradually decreased, and recovered to the preoperative level on day 14 and 21 ( P>0.05), respectively. T2 value was correlated with hepatocyte diameter, liver volume and Ki-67 indices better ( r=0.640, -0.764, 0.765, respectively, all P<0.001). T1 value was correlated with hepatocyte diameter, liver volume and Ki-67 indices ( r=0.472, -0.481 and 0.444, all P<0.001). Conclusion:The T1 and T2 values of rats liver remnant parenchyma showed regular changes, and were correlated with liver regeneration indices, which reflect the microscopic changes of rat liver remnant parenchyma, and are expected to be used for quantitative monitoring of liver remnant regeneration.

The value of MR T 1rho for assessing the evolution and severity of liver fibrosis in carbon tetrachloride model rats / 中华放射学杂志

Objective:To investigate the changes of liver spin-lattice relaxation time (T 1rho) values in the rotating frame in the progression and regression of carbon tetrachloride (CCl 4)-induced model rats with liver fibrosis and the diagnostic values for staging liver fibrosis. Methods:Eighty rats were prospectively enrolled and randomly divided into the CCl 4 group ( n=49), the regression group ( n=20) and the control group ( n=11). All rats were labeled and then examined using MRI at baseline. The liver fibrosis model was established by subcutaneous injection of 40% CCl 4 in hackles. The CCl 4 group underwent black-blood T 1rho imaging at the end of the 4th, 6th, 8th, 10th, 12th week post CCl 4 injection. The regression group underwent black-blood T 1rho imaging at the end of the 4th, 6th week post CCl 4 injection and the end of 1st, 2nd, 4th, 6th week post CCl 4 withdrawal (the injection was stopped at the end of the 6th week). The control group was injected with the same amount of corn oil at the same time point and underwent black-blood T 1rho imaging at the end of 4th, 6th, 8th, 10th, 12th week. The liver T 1rho values were measured in each group over time. Independent-samples t test was used to analyze the differences of liver T 1rho values in adjacent time points. The experimental mice were divided into no liver fibrosis group (S0), mild liver fibrosis group (S1, 2) and moderate or severe liver fibrosis group (S3, 4). The differences of liver T 1rho values were analyzed in different fibrosis stages by Kruskal-Wallis H test. The receiver operating characteristic (ROC) curve analysis was used to evaluate the diagnostic ability of T 1rho values in staging liver fibrosis. The correlation between liver T 1rho values and fibrosis stages was analyzed using Spearman correlation coefficient. Results:Fifty-nine rats completed the whole experiment, including 28 rats in the CCl 4 group, 20 rats in the recovery group and 11 rats in the control group. In the CCl 4 group, the liver T 1rho values gradually increased, reached the maximum at the end of week 8, and then gradually decreased. There was statistically significance in liver T 1rho values at the adjacent time points ( P<0.05) except at the 4th to 6th week ( P=0.112) and 10th to 12th week ( P=0.487) in the CCl 4 group. In regression group, the liver T 1rho values gradually increased post CCl 4 injection and decreased post CCl 4 injection withdrawal. There was statistically significance in liver T 1rho values at the adjacent time points ( P<0.05) in regression group. There was no statistically significance in liver T 1rho values at the adjacent time points ( P>0.05) in control group. The T 1rho values in the no liver fibrosis group (S0, n=15), the mild liver fibrosis group (S1, 2, n=23) and the moderate or severe liver fibrosis group (S3, 4, n=21) were [36.3(34.4,41.4)], (47.2±8.4), (48.8±9.0) ms, respectively. The liver T 1rho values increased with the aggravation of the liver fibrosis, and there was a low positive correlation between them ( r=0.402, P=0.001). There were statistically significant differences in T 1rho values among the three groups ( P<0.01).The area under the curve values to distinguish no liver fibrosis (S0) from liver fibrosis (S1 to 4) and no or mild liver fibrosis (S0 to 2) from moderately or severe liver fibrosis (S3,4) were 0.825 (95% confidence intervals is 0.720 to 0.931) and 0.668 (95% confidence intervals is 0.540 to 0.796), separately. Conclusion:The liver T 1rho values are useful for evaluating the progression and regression of liver fibrosis. It has a moderate diagnostic value to assess the presence of liver fibrosis, but a low diagnostic value to differentiate no or mild liver fibrosis from moderately to severe liver fibrosis.

Diagnostic value of Gd-EOB-DTPA enhanced MRI compared with contrast-enhanced ultrasound for small hepatocellular carcinoma / 实用放射学杂志

Objective To compare the diagnostic value of Gadolinium-ethoxybenzyl-diethylenetriamine pentaacetic acid (Gd-EOB-DTPA) enhanced MRI and contrast-enhanced ultrasound (CEUS) in detection of small hepatocellular carcinoma (sHCC).Methods A total of 22 patients with 29 lesions who underwent Gd-EOB-DTPA enhanced MRI and CEUS scan,and confirmed as sHCCs by pathology were included in this study.Gd EOB DTPA enhanced MRI pattern for the conclusive diagnosis of sHCC were lesions showed iso or low signal on T1 WI,showed slightly high signal or high signal on T2 WI,showed high signal on DWI and obviously enhanced in the arterial phase and/or clearance in the hepatobiliary phase;CEUS pattern for the conclusive diagnosis of sHCC were rapidly increasing in the arterial phase and showing low echo in the delay phase.Results The diagnostic sensitivity of detecting sHCC by Gd EOB-DTPA enhanced MRI and CEUS were 82.76％ and 65.52％ respectively,and there was no statistical difference (x2 =2.248,P=0.134),the diagnosis specificity were both 100 ％.Conclusion Both of the diagnostic sensitivity and specificity for detecting sHCC by Gd EOB DTPA enhanced MRI and CEUS showed no difference,the value of diagnostic sensitivity of the former is higher.

Series review of radioembolization with yttrium-90 microspheres (Part Ⅳ): dose calculation of yttrium-90 microspheres / 介入放射学杂志

Accurate doses of yttrium-90 (90Y) microspheres are critical for the treatment of liver malignancies,because it is closely related to the clinical efficacy and adverse reactions.The dose calculationis primarily based on the type of ~Y delivery medium,whether it is glass microsphere (TheraSpheres) or resin microsphere (SIR-Spheres).The dose calculation of glass microspheres is based on the assumption that the expected radiation dose of the liver and the microspheres can be evenly distributed throughout the liver,while the dose calculation of resin microspheres is based on the assumption that the microspheres are not uniformly distributed throughout the liver,and the degree of this inhomogeneous distribution depends on the extent to which the normal liver is replaced by the tumor tissue.Many other factors may also potentially affect the therapeutic dose of 90Y microspheres.This review will introduce the calculation methods of 90Y microsphere dose,and describe the factors that need to be considered in order to achieve maximum efficacy and avoid adverse effects.

The study of diffusion kurtosis imaging value for assessing liver fibrosis and comparison with ultrasound elastography / 中华放射学杂志

Objective To explore the efficacy difference of diffusion kurtosis imaging (DKI) and ultrasound elastography (UE) in the diagnosis of liver fibrosis. Methods Thirty-five patients whose serological examination showed hepatitis B or hepatitis C virus infection, disease course≥ 1 year, and finally liver biopsy confirmed pathological fibrosis grade in Tianjin Second People's Hospital from December 2015 to April 2017 were prospectively enrolled as patient group. During the same period, twenty healthy volunteers who matched the age, sex and BMI with patient group and showed normal liver function within the last month were enrolled as control group. All of the subjects underwent DKI experiment, and subjects in patient group underwent UE experiment in addition. Liver mean apparent diffusion (MD) and mean kurtosis (MK) were obtained in all subjects and liver stiffness measurement (LSM) was obtained in patient group. The patient group was staged for hepatic fibrosis based on liver biopsy results (S0 to S4). Differences in liver MD and MK values between control and patient groups were tested using independent sample t test (normal distribution) or Mann-Whitney U test (skewed distribution). Differences in liver MD, MK, and LSM between patients with different fibrosis stages were tested using One-way ANOVA (normal distribution) or Kruskal-Wallis test (skewed distribution). The correlation between liver MD, MK and LSM values with fibrosis stages were analyzed using Pearson correlation test. The diagnostic performance in staging fibrosis was analyzed using ROC analysis. Results Liver MD in patient group was lower than that in control group, and the difference was statistically significant (P<0.01). There was no significant difference in liver MK between the two groups (P>0.05). The AUC value for the diagnosis of liver fibrosis by MD was 0.950 (95％CI:0.855 to 0.990). Of the 35 patients, 15 were S1 (mild fibrosis), 13 were S2 (moderate fibrosis), 4 were S3, 3 were S4 (S3+S4 were severe fibrosis). The difference of MD and LSM between different stages of liver fibrosis was statistically significant (P<0.05), and there was no significant difference in MK (P>0.05). Liver fibrosis stages was highly correlated with MD (r=-0.757, P<0.01), and had no correlation with MK (r=-0.010, P=0.956), and moderately correlated with LSM (r=0.440, P<0.01). The AUC values of liver MD and LSM for characterization of ≥S2 stage liver fibrosis were 0.867 and 0.800, respectively, without statistically significant difference (P=0.486). The AUC values for characterization of≥S3 stage liver fibrosis were 0.918 and 0.653, respectively, with a statistically significant difference (P=0.032). Conclusion MD derived from DKI can be used for noninvasive assessment of liver fibrosis, and it is superior to LSM in distinguishing different fibrosis stages and detecting severe fibrosis.

Brain Regional Homogeneity Changes in Cirrhotic Patients with or without Hepatic Encephalopathy Revealed by Multi-Frequency Bands Analysis Based on Resting-State Functional MRI

OBJECTIVE: To investigate brain regional homogeneity (ReHo) changes of multiple sub-frequency bands in cirrhotic patients with or without hepatic encephalopathy using resting-state functional MRI. MATERIALS AND METHODS: This study recruited 46 cirrhotic patients without clinical hepatic encephalopathy (noHE), 38 cirrhotic patients with clinical hepatic encephalopathy (HE), and 37 healthy volunteers. ReHo differences were analyzed in slow-5 (0.010−0.027 Hz), slow-4 (0.027−0.073 Hz), and slow-3 (0.073−0.198 Hz) bands. Routine analysis of (0.010−0.080 Hz) band was used as a benchmark. Associations of abnormal ReHo values in each frequency band with neuropsychological scores and blood ammonia level were analyzed. Pattern classification analyses were conducted to determine whether ReHo differences in each band could differentiate the three groups of subjects (patients with or without hepatic encephalopathy and healthy controls). RESULTS: Compared to routine analysis, more differences between HE and noHE were observed in slow-5 and slow-4 bands (p 12, overall corrected p < 0.05). Sub-frequency band analysis also showed that ReHo abnormalities were frequency-dependent (overall corrected p < 0.05). In addition, ReHo abnormalities in each sub-band were correlated with blood ammonia level and neuropsychological scores, especially in the left inferior parietal lobe (overall corrected p < 0.05 for all frequency bands). Pattern classification analysis demonstrated that ReHo differences in lower slow-5 and slow-4 bands (both p < 0.05) and higher slow-3 band could differentiate the three groups (p < 0.05). Compared to routine analysis, ReHo features in slow-4 band obtained better classification accuracy (89%). CONCLUSION: Cirrhotic patients showed frequency-dependent changes in ReHo. Sub-frequency band analysis is important for understanding HE and clinical monitoring.

Aterial Spin Labeling Evaluation of Residual Renal Function After Partial Nephrectomy on Renal Cell Carcinoma / 中国医学影像学杂志

Purpose To investigate the value of arterial spin labeling (ASL) in evaluating renal function in patients with renal cell carcinoma (RCC) after laparoscopic partial nephrectomy.Materials and Methods Fifteen patients with RCC undergoing laparoscopic partial nephrectomy were studied prospectively.The patients were performed ASL scan one week before and three months after operation.The correlation between renal blood flow (RBF) value measured by ASL and the glomerular filtration rate (GFR) measured by radionuclide method in the renal cortex of healthy side was analyzed.The RBF values in the kidney of affected side or healthy side were measured,the difference of which between before operation and three months after operation was compared.Results The RBF value and GFR data in the renal cortex of healthy side had positive correlation (r=0.638,P＜0.05).In the affected side of kidney,the RBF value of remaining renal tissue [(291.5 ± 37.3) ml/(100g·min)] compared with that of preoperative renal tissue [(237.8 ± 46.2) ml/(100g·min)]increased about 53.7 ml/(100g · min) (P＜0.05).In the healthy side of kidney,the RBF value of renal tissue [(241.1 ± 50.3) ml/(100 g · min)] compared with that of preoperative renal tissue [(290.4 ± 51.8) ml/(100 g·min)] decreased about 49.3 ml/(100 g·min) (P＜0.05).Conclusion ASL can be used to evaluate renal function,and it is valuable to evaluate renal perfusion function after laparoscopic partial nephrectomy of RCC.

Correlation research of renal perfusion and diffusion function using MRI in renal allograft early after renal transplantation / 中华放射学杂志

Objective To explore the correlationships between microperfusion diffusion indexes derived from intravoxel incoherent motion(IVIM)and perfusion values measured by arterial spin labeling (ASL)in renal allograft. Methods A total of 76 renal allograft recipients and 26 age-matched volunteers (group 0)were included in this prospective study. All subjects were underwent conventional MRI, IVIM and ASL MRI which were performed in the oblique-sagittal plane. Seventy-six recipients were divided into two groups based on the estimated glomerular filtration rate(eGFR):recipients with good allograft function(group 1, eGFR≥ 60 ml · min-1 · 1.73m-2,n=44)and recipients with impaired allograft function(group 2, eGFR0.05), but RBF value was significantly lower(P<0.05). The ADCslow, ADCfast, PF and RBF values of renal cortex were significantly lower in allografts with impaired function compared to allografts with good function(all P<0.01). In renal allografts, there were significant positive correlations between cortical ADCslow, ADCfast, PF, RBF value and eGFR(r values were 0.604, 0.552, 0.579 and 0.673, all P<0.01). Cortical ADCfast and PF value exhibited a significant correlation with RBF for recipients(r values were 0.501 and 0.423, all P<0.01). Conclusion Cortical ADCfast and PF values derived from IVIM and RBF measured by ASL show a significant positive correlation in renal allografts.

Pretherapeutic aassessment of the hepatic arterial vasculature for hepatic malignancy with yttrium-90 radioembolization.A series review of radioembolization with 90Y microspheres (part Ⅲ) / 介入放射学杂志

Potential complications arising from yttrium-90 (90Y) radioembolization are often related to inadvertent embolization of non-target vasculature during particle administration.Therefore,careful pretherapeutic planning with arterial mapping is especially important to help identify potential high-risk arteries and vascular communications.A complete pre-therapeutic evaluation of hepatic arterial vasculature includes selective arteriography,precautionary embolization of potential risk arteries and identification of occurrences of hepatopulmonary shunting secondary to tumor-related pathologic arteriovenous channels.The aim of this review is to discuss the pertinent arterial anatomy during 90Y radioembolization therapy and strategies on how to evaluate the risk and prevent the occurrence of non-target embolization through those vascular structures.

Feasibility study of MR T2-mapping for evaluating birth-related levator ani muscle injury / 实用放射学杂志

Objective To investigate MR T2-mapping in evaluating birth-related levator ani muscle injury.Methods 25 primiparas at 6 weeks after first vaginal delivery as primiparous group and 12 nulliparous volunteers as control group were prospectively studied. All the subjects underwent pelvic MRI including T2-mapping,mDIXON-T2 WI sequences.Levator ani muscle were divided into two subgroups:levator ani muscle injury group and non-injury group according to if there were edema,avulsion,or rupture in each levator ani muscle subdivisions[puborectal muscle(PRM);iliococcygeal muscle(ICM)],which were showed on mDIXON-T2 WI images.Two radiologists evaluated T2 values of PRM,ICM and observed artificial color images respectively.The consistency between two observers for T2 values of PRM,ICM were evaluated using the intraclass correlation coefficient (ICC ),the difference of T2 values in each levator ani muscle subdivisions among control group,non-injury group and muscle injury group were analyzed using ANOVA .Results There were 26 PRM injury cases and 24 non-injury cases in primiparous group on mDIXON-T2 WI images,and no ICM injured cases in our study.Inter-rater reliability for T2 values between two observers were good(ICC >0.75).T2 values in PRM injury group,non-injury group and control group were(62.78±1.23)ms,(49.75±3.17)ms,(49.96±4.37)ms respectively and the difference was significant. There were significant difference between PRM injury group and non-injury group,control group respectively(P =0.000,P =0.000). The T2 values of ICM in PRM injury group,non-injury group and control group were(70.80±6.50)ms,(62.41±7.32)ms,(62.78±6.91)ms and there were significant difference(P =0.000),meanwhile the difference between PRM injury group and non-injury group,control group were significant respectively(P =0.000,P =0.000).The color gradation of PRM in PRM injury group were mixed with blue, green,and yellow,and tone were lightened on T2-mapping artificial color images;ICM color gradation were uneven with green and yellow, a d tone were higher than those of control group and non-injurygroup.Conclusion T2-mapping can quantitatively assess birth-related levator ani muscle injury and T2-mapping artificial color images show the range and degree of levator ani muscle injury visually.It is hopeful to find micro lesions that T2 WI images are difficult to find.

Feasibility study of MR T2-mapping for evaluating birth-related levator ani muscle injury / 实用放射学杂志

Objective To investigate MR T2-mapping in evaluating birth-related levator ani muscle injury.Methods 25 primiparas at 6 weeks after first vaginal delivery as primiparous group and 12 nulliparous volunteers as control group were prospectively studied. All the subjects underwent pelvic MRI including T2-mapping,mDIXON-T2 WI sequences.Levator ani muscle were divided into two subgroups:levator ani muscle injury group and non-injury group according to if there were edema,avulsion,or rupture in each levator ani muscle subdivisions[puborectal muscle(PRM);iliococcygeal muscle(ICM)],which were showed on mDIXON-T2 WI images.Two radiologists evaluated T2 values of PRM,ICM and observed artificial color images respectively.The consistency between two observers for T2 values of PRM,ICM were evaluated using the intraclass correlation coefficient (ICC ),the difference of T2 values in each levator ani muscle subdivisions among control group,non-injury group and muscle injury group were analyzed using ANOVA .Results There were 26 PRM injury cases and 24 non-injury cases in primiparous group on mDIXON-T2 WI images,and no ICM injured cases in our study.Inter-rater reliability for T2 values between two observers were good(ICC >0.75).T2 values in PRM injury group,non-injury group and control group were(62.78±1.23)ms,(49.75±3.17)ms,(49.96±4.37)ms respectively and the difference was significant. There were significant difference between PRM injury group and non-injury group,control group respectively(P =0.000,P =0.000). The T2 values of ICM in PRM injury group,non-injury group and control group were(70.80±6.50)ms,(62.41±7.32)ms,(62.78±6.91)ms and there were significant difference(P =0.000),meanwhile the difference between PRM injury group and non-injury group,control group were significant respectively(P =0.000,P =0.000).The color gradation of PRM in PRM injury group were mixed with blue, green,and yellow,and tone were lightened on T2-mapping artificial color images;ICM color gradation were uneven with green and yellow, a d tone were higher than those of control group and non-injurygroup.Conclusion T2-mapping can quantitatively assess birth-related levator ani muscle injury and T2-mapping artificial color images show the range and degree of levator ani muscle injury visually.It is hopeful to find micro lesions that T2 WI images are difficult to find.

The prompt value of abnormal vaginal morphology on MRI for diagnosing pelvic organ prolapse / 中华放射学杂志

Objective To investigate the prompt value of abnormal vaginal morphology on diagnosing pelvic organ prolapse . Methods Forty eight pelvic organ prolapse female patients diagnosed by pelvic organ prolapse quantification were enrolled in the pelvic organ prolapse group and 51 normal female volunteers were enrolled in the control group in this study. Pelvic MRI T2WI were performed in all cases. The vaginal shape were evaluated according to Delancey Ⅱ level on the transverse images, which were divided into two categories:normal morphology (H-shaped) and abnormal morphology(non H-shaped). The vaginal shape distribution of different prolapse degree(0,Ⅰ,Ⅱ,Ⅲ,Ⅳstage) and types(anterior,middle, posterior pelvic prolapse) were recorded. Chi-square test was used to analyse distribution difference of vaginal shape between the two groups. The ROC curve was used to analyse the diagnostic efficiency of abnormal vaginal morphology for diagnosing pelvic organ prolapse. Results In the control group, there were 40 cases with normal vaginal morphology and 11 cases with abnormal morphology mainly including W-shaped and U-shaped abnormal morphology. In the prolapse group, there were 5 cases with normal vaginal morphology and 43 cases with abnormal morphologymainly including U-shaped (13 cases), W-shaped (26 cases) and O-shaped(4 cases) abnormal morphology. There was significant difference between the two groups(c2=46.137,P<0.01). The area under the curve (AUC) was 0.800. The sensitivity and specificity of abnormal vaginal shape for diagnosing pelvic organ prolapse were 89.6% and 78.4%respectively.The distribution of vaginal morphology in different degrees and types of prolapse were different:vaginal morphology of 0 stage prolapse showed H-typed mainly (40/51, 78.4%), Ⅰ stage prolapse showed W-shaped (16/28 57.1%), Ⅱ,Ⅲ stage prolapse all showed non H-shaped (20/20, 100%), Ⅱstage mainly showed W-shaped (9/14), Ⅲ stage mainly showed O-shaped (3/6). Anterior pelvic organ prolapse were manifested mainly with W-shaped vaginal morphology (4/9) and middle pelvic organ prolapse mainly showed O-shaped vaginal morphology (4/7). Conclusions The abnormal vaginal morphology has the prompt value on diagnosing pelvic organ prolapse.Moreover, the different shape probably indicates the different degrees and types of pelvic organ prolapse.

Impact of Liver Fibrosis and Fatty Liver on T1rho Measurements: A Prospective Study

OBJECTIVE: To investigate the liver T1rho values for detecting fibrosis, and the potential impact of fatty liver on T1rho measurements. MATERIALS AND METHODS: This study included 18 healthy subjects, 18 patients with fatty liver, and 18 patients with liver fibrosis, who underwent T1rho MRI and mDIXON collections. Liver T1rho, proton density fat fraction (PDFF) and T2* values were measured and compared among the three groups. Receiver operating characteristic (ROC) curve analysis was performed to evaluate the T1rho values for detecting liver fibrosis. Liver T1rho values were correlated with PDFF, T2* values and clinical data. RESULTS: Liver T1rho and PDFF values were significantly different (p 0.05). CONCLUSION: T1rho MRI is useful for noninvasive detection of liver fibrosis, and may not be affected with the presence of fatty liver.

Assessment of early renal allograft function after transplantation using renal intravoxel incoherent motion imaging and T1 mapping / 中华放射学杂志

Objectives To investigate the ability of T1 mapping and intravoxel incoherent motion imaging (IVIM) parameters for evaluating renal allografts at the early stage after renal transplantation. Methods This prospective study protocol was approved by the local ethics committee, and written informed consent was obtained from all subjects. Sixty two recipients 2 to 4 weeks after kidney transplantation and 20 healthy volunteers (control group) underwent routine MRI, T1 mapping, and IVIM imaging (11 b values, 0 to 700 s/mm2). Recipients were divided into two groups base on their estimated glomerular filtration rate (eGFR):37 recipients with good allograft function (eGFR≥60 ml·min-1·1.73 m-2) and 25 recipients with impaired allograft function (eGFR<60 ml·min-1·1.73 m-2). The ADC, true diffusion coefficient (ADCslow), pseudo-diffusion coefficient (ADCfast), perfusion fraction (f) and T1 values were measured on both cortex and medulla. Differences among groups were compared using the one-way analysis of variance. Correlations between eGFR and the parameters in renal allografts were assessed by using Pearson correlation analysis. ROC was performed to assess the diagnostic utilities of using these parameters to discriminate allografts with impaired function from good function. Results Excepting for cortical T1, ADCfast and medullary T1, f values, allografts with good function showed no differences in other parameters compared with healthy control. Excepting for medullary T1 and ADCfast,the other values showed significantly differences in allografts with impaired function compared to allografts with good function (all P<0.05). Excepting for medullary f and ADCfast values, allografts with impaired function showed significantly differences in the parameters compared with good function group(all P<0.05). In renal allografts, excepting for medullary T1, ADCfast, and f values, cortical T1 exhibited a negative correlation with renal function, and there was a significant positive correlation between eGFR and other parameters. Cortical T1 value showed high sensitivity(91.9%) to discriminate renal allografts with different function, with the threshold of 17.36 × 102 ms, and ADC value showed high specificity(96.0%)with the threshold of 1.98 × 10-3 mm2/s. Conclusion T1 mapping and IVIM technique may be useful for detecting renal allograft dysfunction, and be a reliable imaging for evaluating and monitoring allograft function.

Applied value of 3.0T blood oxygen level dependent (BOLD) MRI in the diagnosis of hepatic warm ischemia-reperfusion injury (WIRI) in rabbits / 中华器官移植杂志

Objective To investigate the applied value of 3.0T blood oxygen level dependent(BOLD) MRI in the diagnosis of hepatic warm ischemia-reperfusion injury (WIRI) in rabbits.Method Twenty healthy adult New Zealand white rabbits were randomly divided into two groups by using the stochastic indicator method.In 10 rabbits enrolled in the treatment group,the model of hepatic WIRI after ischemia for 30 min followed by 6-h reperfusion was established,and the remaining 10 rabbits were chosen as the normal control group and were not subjected to any surgery.All the experimental rabbits were scanned by 3.0T MRI and BOLD MRI.T2* values were separatelymeasured by 2 considered radiologists and the R2* values were calculated (R2* =1/T2*).Thereafter,the intra-class correlation coefficient (ICC) was used to check the consistency.All rabbits were killed after MR examination and routine assays were performed for testing the levels of alanine aminotransferase (ALT),aspartate aminotransferase (AST),and lactate dehydrogenase (LDH) in the ear vein blood serum.The contents of total superoxide dismutase (SOD),malondialdehyde (MDA) and myeloperoxidase (MPO) in liver tissues were determined,and histopathological changes were examined.The correlation between R2 * value and clinical test index was evaluated by Spearman correlation analysis.The R2* value was evaluated by ROC curve.Result ICC =0.87 ＞ 0.75,suggesting that the repeatability of the outcome is good.Compared to the normal control group,R2*value of the warm ischemia-reperfusion injury group was increased (P =0.000).The differences in ALT,AST,LDH,total SOD,MDA and MPO between the two groups were statistically significant (P＜0.01).R2* values were significantly positively correlated with ALT,AST,LDH,MDA and MPO (r＞0.6,P＜0.05),and there was a significantly negative correlation between R2* and total SOD (r=-0.663,P=0.001).The R2* value could efficiently diagnose rabbit hepatic WIRI (AUC =0.99) with the best diagnostic threshold being 116.40 Hz.Conclusion 3.0T BOLD MRI can accurately and non-invasively assess the pathophysiologic changes caused by WIRI.It is of great importance for 3.0T BOLD MRI in dynamically monitoring and evaluating hepatic WIRI.

The value of arterial spin labeling MRI for evaluating early renal allograft function / 中华放射学杂志

Objective To assess the value of arterial spin labeling(ASL) MRI in the staging of early renal allograft function. Methods Sixty two renal allograft recipients (2 to 4 weeks after kidney transplantation) and 20 age match volunteers were included in this study. All subjects underwent conventional MRI and ASL MRI which was performed in the oblique-sagittal plane. Recipients were divided into two groups according to the estimated glomerular filtration rate (eGFR), recipients with good allograft function (eGFR≥60 ml · min-1 · 1.73 m-2,n=37) and recipients with impaired allograft function (eGFR<60 ml · min - 1 · 1.73 m - 2,n=25). Renal blood flow (RBF) was measured and an intra-class correlation coefficient (ICC) was calculated to confirm the reproducibility of the measured results from two doctors. One-way analysis of variance (ANOVA) and Bonferroni were used to compare the different cortical RBF among three groups. Correlation of RBF with eGFR was evaluated using Pearson correlation coefficients. The receiver operating characteristic (ROC) curve was performed to assess the diagnostic efficacy of using cortical RBF to discriminate allografts with impaired function from good function. Results RBF values showed good reproducibility between doctors with an ICC larger than 0.90 in different group. Mean cortical RBF were (390 ± 61),(290 ± 69),(201 ± 86) ml · 100 g-1 · min-1 for healthy controls, recipients with good and impaired allograft function, respectively(F=37.313,P<0.01). RBF exhibited a significant correlation with renal function as determined by eGFR for recipients (r=0.60,P<0.01). Mean cortical RBF showed a high area under the ROC curve (0.773) to discriminate renal allografts with different function, with a sensitivity of 56.0% (14/25) and a specificity of 89.2% (33/37). Conclusion ASL MRI can assess the early renal allografts perfusion, and provide valuable information in the staging of renal function. It could be a useful method for evaluating renal function noninvasively.

Research advances on the evaluation of regional liver function based on the demand of precise liver surgery / 中华外科杂志

Surgical resection is the best treatment for hepatocarcinoma. With the rapid development and cooperation of multi-disciplines, the liver surgery gradually towards a precise stage, and accurate evaluation of regional liver function preoperatively is demand for the development of precise liver surgery. Methods to assess function of liver at present include serological liver function and biochemical examination, clinical liver function scoring system, quantitative liver function test and imaging examination. Nuclide imaging technology and liver specificity enhanced MRI contrast agent are expected to achieve to evaluate regional liver function.

Relationship between liver enhancement in hepatobiliary phase of gadolinium ethoxybenzyl diethylenetriamine pentaacetic acid-enhanced MRI and liver function / 中华放射学杂志

Objective To evaluate the effect of liver function on liver enhancement in hepatobiliary phase of gadolinium ethoxybenzyl diethylenetriamine pentaacetic acid(Gd-EOB-DTPA)-enhanced MRI.Methods Sixty-seven patients who suffered from cirrhosis and received enhanced MRI with Gd-EOB-DTPA were retrospectively analyzed,and divided into three subgroups according to ChildPugh score(45 patients in group A,20 in group B,5 in group C).All the individuals of both groups had MRI before injection,and hepatobiliary phase images were obtained at 5,10,and 20 minutes after bolus administration of Gd-EOB-DTPA.The relative enhancement(RE) was calculated by dividing the signal intensity of liver(SI) at t min after injection(SIt) by precontrast SI(SI0).The total serum bilirubin level(TB),serum albumin level(Alb) and prothrombin time(PT) were recorded.The one-way ANOVA was used to compare the RE among three groups at 5,10 and 20 minutes.SNK was used for further pairwise comparison.The effect of liver function on RE was assessed with the generalized linear model.Pearson correlation coefficients were measured between each biochemical test result(TB,Alb,PT) and RE at different time points.Results The RE at 5,10 and 20 minutes were 1.59±0.20,1.65±0.22,1.69±0.25 of group A; 1.47± 0.14,1.48±0.18,1.50±0.22 of group B,1.35±0.07,1.27±0.06,1.26±0.06 of group C.There were statistically significant differences of RE among groups at 5,10 and 20 minutes(F=5.854,11.207,9.666,P＜0.01).Statistically pairwise comparison differences of RE were found between group A and C at 5,10 and 20 minutes(P＜0.01),between B and C at 10 and 20 minutes(P＜0.05),between A and B at 10 minutes(P＜ 0.05).There were statistically significant differences of TB,Alb and PT among groups(P＜0.01).RE at 10 and 20 minutes had moderate negative correlation with TB(r=-0.483,-0.500; P＜0.01),low negative correlation with PT(r=-0.326,-0.351;P＜0.01) and weak positive correlation with Alb(r=0.290,0.292;P＜0.05).Conclusions There are differences of RE among patients with different liver function,and the RE is associated with TB,Alb and PT.Thus,it may allow us to estimate the liver function.