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Objective:To explore the feasibility of cardiac T 2 weighted dark blood sequence (T 2W-DB) based on artificial intelligence assisted compression-sensing(ACS) in clinical cardiac MR examination, compared with the conventional cardiac fast spin-echo T 2W-DB sequence. Methods:A total of 38 patients referred for cardiac MR examination in Tongji Hospital were enrolled prospectively from August to December 2021. The conventional T 2W-DB scan and the single-shot ACS T 2W-DB scan were acquired at continuous short-axial slices covering the whole left ventricle in all patients, and the acquisition time of each scan was recorded. The image quality of the two sequences was evaluated by the objective quantitative parameters and the subjective scoring methods, respectively. The signal to noise ratio (SNR), the contrast to noise ratio of the interventricular septum to blood pool (CNR), and the sharpness of the images were calculated. The subjective scoring was to evaluate the overall image quality, the effect of blood pool suppression, the visibility of right ventricular free wall, left ventricular free wall, and interventricular septum with a 5-point Likert scale. The intraclass correlation coefficient and Kendall W were calculated to evaluate the interobserver agreement of the objective quantitative parameters and subjective scoring. The paired t-test or Wilcoxon test was used to compare the difference in acquisition time, objective quantitative parameters and subjective scoring between the conventional T 2W-DB and the single-shot ACS T 2W-DB. Results:The inter-observer agreement between the single-shot ACS T 2W-DB and conventional T 2W-DB was good in all the objective quantitative parameters and subjective scoring of image quality ( P<0.05 for all). Compared with conventional T 2W-DB, acquisition time of single-shot ACS T 2W-DB was remarkably shortened [(85.8±14.7) s vs. (16.9±3.0) s, t=35.42, P<0.001]. Compared with SNR (66.4±29.0) and CNR(61.8±28.6) of conventional T 2W-DB, single-shot ACS T 2W-DB had significantly higher SNR(110.8±36.8, t=-8.13, P?0.001) and CNR(88.2±31.1, t=-5.89, P?0.001). Compared with conventional T 2W-DB, single-shot ACS T 2W-DB had better blood pool inhibition effect (4.6±0.6 vs. 4.7±0.5, Z=-2.64, P=0.008). There was no significant difference in overall image quality, visibility of right ventricular free wall, left ventricular free wall, and interventricular septum between the two sequences( P>0.05 for all). Conclusions:In cardiac MR examination, compared with the conventional T 2W-DB sequence, the single-shot ACS T 2W-DB sequence can significantly shorten the acquisition time and obtain better image quality.
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Objectives:To explore the value of blood oxygen level-dependent (BOLD) MRI in evaluating the changes of placental oxygenation during maternal hyperoxia.Methods:From October 2017 to March 2020, 22 singleton pregnant women with normal placenta showed by ultrasound were prospectively included in Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology. Pregnant women wore oxygen mask before examination, and then underwent BOLD MRI examination for 10 min. The pregnant women inhaled air in the first 3 min and continuously inhaled oxygen with purity greater than 90% in the next 7 min (flow rate 12 L/min). The average value of BOLD signal of the whole placenta, fetal side of placenta, maternal side of placenta and maternal kidney were measured and calculated in the first 3 min as before oxygen and the last 3 min of the end of oxygen inhalation as after oxygen. The ΔBOLD was calculated which was the change value of BOLD signal before and after oxygen inhalation. The BOLD values of placenta and maternal kidney before and after oxygen inhalation were compared by using paired t-test. The ΔBOLD of the whole placenta, the fetal side of the placenta and the maternal side of the placenta were compared by using one-way ANOVA, and the LSD method was used for pairwise comparison between groups. Results:There were significant differences in BOLD values of the whole placenta, fetal side of placenta and maternal side of placenta before and after oxygen inhalation ( t=-4.62, P<0.001; t=-4.73, P<0.001; t=-3.57, P=0.002). There was no significant difference in BOLD value of maternal kidney before and after oxygen inhalation ( t=0.35, P=0.740). The ΔBOLD values of the whole placenta, fetal side of placenta and maternal side of placenta were (12.8±2.2)%, (15.1±2.7)% and (6.4±1.3)% respectively. The overall difference was statistically significant ( F=4.49, P=0.015). The results of pairwise comparison showed that there was no significant difference in ΔBOLD between the whole placenta and the fetal side of the placenta ( P=0.450). There were significant differences in ΔBOLD between whole placenta and maternal side of placenta ( P=0.037) and between fetal side and maternal side of placenta ( P=0.005). Conclusion:Under the condition of maternal hyperoxia, the BOLD signal of placenta increased significantly, and the change of fetal side of placenta was more obvious than that of maternal side. BOLD-MRI has the potential of semi-quantitative and real-time evaluation of placental oxygenation.
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Objective:To evaluate the value of cardiac MR feature tracking (CMR-FT) on the early assessment of left ventricular subclinical myocardial dysfunction in patients of hypertensive heart disease (HHD).Methods:From October 2018 to November 2019, 16 HHD patients with left ventricular hypertrophy (HHD-LVH), 24 HHD patients without left ventricular hypertrophy (HHD-nonLVH) and 24 age-and gender-matched normotensive controls who underwent 3.0 T CMR examination were retrospectively enrolled. Imaging protocol included cine sequence and late gadolinium enhancement. Left ventricular function variables were measured using Argus software, mainly including left ventricular end-diastolic volume index (LVEDVI), left ventricular mass index (LVMI), left ventricular maximal wall thickness (LVMWT), the ratio of left ventricular mass to left ventricular end-diastolic volume (M/V). CMR-FT was performed using commercial software CVI 42, with parameters including global radial, circumferential, longitudinal strains (GRS, GCS, GLS), peak systolic radial, circumferential, longitudinal strain rate (SRSR peak, SCSR peak, SLSR peak) and peak diastolic radial, circumferential, longitudinal strain rate (DRSR peak, DCSR peak, DLSR peak) derived. One-way analysis of variance with scheffe correction or Kruskal-Wallis test was performed for multiple comparisons. Pearson or Spearman analysis was used for linear or monotonic nonlinear correlations. Results:HHD-LVH group had higher LVEDVI, LVMI, LVMWT and M/V than HHD-nonLVH group and control group ( P<0.05). Compared with control group, GRS, GCS and GLS were statistically impaired in HHD-LVH group, and DRSR peak, DCSR peak and DLSR peak were statistically reduced in HHD-LVH group and HHD-nonLVH group(all P<0.05). Correlation analysis showed that LVMI correlated linearly with GRS ( r=-0.384, P=0.002), GCS ( r=0.392, P=0.001) and GLS ( r=0.491, P<0.0001),LVMWT correlated nonlinearly with GRS ( r=-0.362, P=0.003), GCS ( r=0.384, P=0.002) and GLS ( r=0.422, P=0.001), LVEDVI correlated nonlinearly with GRS ( r=-0.295, P=0.018) and GCS ( r=0.264, P=0.035). Conclusion:CMR-FT derived left ventricular strain parameters could be served as early indicators for the assessment of subclinical myocardial dysfunction in HHD patients, which have great potential in guiding appropriate intervention therapy and improving cardiac remodeling.
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Objective:To investigate the value of chest CT quantitative index in clinical classification and lung injury severity evaluation of COVID-19.Methods:The current study retrospectively analyzed the clinical and CT data of 438 patients with COVID-19 between January 2020 and March 2020 in Tongji Hospital, Tongji Medical College, Huazhong University of Science & Technology. The clinical types included common type ( n=146), severe type ( n=247) and critical type ( n=45). The chest CT indexes of all patients were quantitatively analyzed by artificial intelligence (AI) deep learning, including whole lung volume, CT lung opacification, ground glass opacification volume (GGO volume; CT value<-300 HU), solid opacification volume (SO volume; CT value ≥-300 HU) and the ratio of volume to the whole lung volume, the ratio of SO volume to GGO volume (SO volume/GGO volume). Kruskal-Wallis test was used to conduct statistical analysis of the differences in quantitative parameters among clinical types, and multiple ordered logistic regression was used to analyze the correlation between quantitative parameters and clinical types. Results:Among the 438 patients diagnosed with COVID-19, severe and critical patients were older ( P<0.05), and most of the critical patients were male ( P<0.05). The main clinical manifestations of all clinical types were fever, followed by cough, fatigue, chest tightness, dyspnea, gastrointestinal symptoms and so on. GGO volume was the main CT manifestation of all the three clinical subtypes. The whole-lung opacification volume, GGO volume, SO volume and their proportions in whole-lung volume significantly increased from common, severe to critical types (all P<0.05). SO volume/GGO volume increased with the severity of clinical type [common type 0.12 (0.03, 0.34), severe type 0.29 (0.11, 0.59), critical type 0.61 (0.39, 0.97)]. Multiple ordered logistic regression analysis showed that whole-lung opacification volume (OR=1.009), SO volume/GGO volume (OR=1.866), GGO volume (OR=1.008) and SO volume (OR=1.016) had a significant positive effect on the severity of clinical typing ( P<0.01). Conclusion:Quantitative indicators of chest CT based on deep learning algorithm (SO volume, GGO volume, SO volume/GGO volume) are closely related to the clinical severity of COVID-19.
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Objective:To investigate the CT and clinical features of COVID-19.Methods:Chest CT and clinical data of 103 patients who were confirmed as COVID-19 in January 2020 were collected retrospectively. According to diagnosis and treatment of COVID-19 (trial version 5), all the patients were classified into common( n=58), severe ( n=36) and critical ( n=9) types, and their clinical findings, laboratory examination and CT finding were analyzed. CT features included distribution, location, size, shape, edge, number and density of the lesion, percentage of pneumonia lesions of the whole lung and extra-pulmonary manifestations. The CT features among different clinical types were compared using χ 2 test or Fisher's exact probability. Comparisons of age, duration from onset to CT examination, and percentage of pneumonic lesions to total lung volume among different types were performed by using analysis of variance (normal distribution) or Kruskal-Wallis rank sum test (non-normal distribution). Results:In terms of clinical manifestations, the patients with critical COVID-19 were more common in elderly men, with a median age of 65 years. Fever was the first symptom in 49 (84%) of 58 common patients, and also the first symptom in both severe and critical COVID-19 patients. The incidence of coughing in severe (25/36, 69%) and critical (6/9, 67%) COVID-19 patients was higher than that in common patients (20/58, 34%). All critical patients had dyspnea. CT showed the common COVID-19 was located in bilateral lung (40/58, 71%)with multiple (40/58, 69%), ground glass (31/58, 52%) or mixed (25/58, 43%)opacities (56/58, 97%), while all the severe and critical COVID-19 were located in bilateral lung(100%) with multiple (34/36, 96%), patchy (33 /36, 92%), or mixed opacities (26/36, 72%) in severe patients, and with mixed opacities more than 3 cm in critical patients. As for the percentage of pneumonia focus in the whole lung volume, the common type (12.5%±6.1%) was significantly lower than the severe type (25.9%± 10.7%) and the critical type (47.2%±19.2%), with statistically significant differences( P< 0.001 and 0.002 respectively), and the severe type COVID-19 was also significantly lower than the critical type ( P= 0.032). Conclusions:CT and clinical features of different clinical types of COVID-19 pneumonia are different. Chest CT findings are characteristic, which can not only help the early diagnosis but also evaluate the clinical course and severity.
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Objective@#To investigate the CT and clinical features of 2019 novel coronavirus (NCP) pneumonia.@*Methods@#Chest CT and clinical data of confirmed 103 patients with 2019 novel coronavirus pneumonia in January 2020, retrospectively. According to diagnosis and treatment of NCP infected pneumonia (trial version 5), all the patients were classified into mild(n=58), severe (n=36) and very severe (n=9) type, and their clinical findings, laboratory examination and CT finding were analyzed. CT features included lesions’ distribution, location, size, shape, edge, number, density, percentage of pneumonia lesions of the whole lung and extra-pulmonary manifestations. The CT features of different clinical subtypes were compared using χ2test or Fisher's exact probability. Comparisons between the percentage of pneumonic lesions to total lung volume were computed by using analysis of variance (normal distribution) or Kruskal-Wallis rank sum test (non-normal distribution).@*Results@#In terms of clinical manifestations, the patients with severe NCP were more common in elderly men, with a median age of 65 years. Fever was the first symptom in 49 (84%) of 58 patients with NCP, and fever was the first symptom in both severe and critical NCP patients. The incidence of cough in severe (25 / 36, 69%) and critical (6 /9, 67%) NCP patients was higher than that in general (20 /58, 34%). All critical patients have dyspnea. In terms of CT findings, common NCP showed double lung (40/58,71%) multiple (40 / 58,69%) ground glass (31/58,52%) or mixed (25 / 58,43%) lesions (56 / 58,97%); severe and critical NCP showed double lung lesions, heavy NCP mainly showed multiple (34 / 36,96%) patches (33 / 36,92%) mixed density lesions (26 / 36,72%); 9 severe NCP lesions were more than 3 cm Mixed density lesions. The percentage of pneumonia focus in the whole lung volume: the common type (12.5% ± 6.1%) was significantly lower than the severe type (25.9% ± 10.7%) and the critical type (47.2% ± 19.2%) NCP, the difference was statistically significant (P values were < 0.001 and 0.002 respectively), and the severe type NCP was also significantly lower than the critical type (P = 0.032).@*Conclusions@#CT and clinical features of different clinical types of NCP pneumonia are different. Chest CT findings have unique characteristic, which can not only make early diagnosis, but also evaluate its clinical course and severity.
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Objective To investigate the role of diffusion kurtosis imaging (DKI) in indeterminate solitary pulmonary nodules (SPN) diagnosis and to compare with conventional diffusion weighted imaging (DWI). Methods From March 2016 to Dec 2017, forty-three consecutive patients (30 male, 13 female, age: 56 ± 11 years) with indeterminate SPNs were included. All patients underwent axial multi-b factor DWI (with b values=0, 50, 200, 400, 800, 1400, 2000 s/mm2) examination and were divided into benign group (19 cases) and malignant group (24 cases) according to pathological results of SPN. ADC Kurtosis (K) and Diffusivity (Dk) values were compared between malignant and benign group and among different subtypes of lung cancer using independent t test (normal distribution and homogeneity of variance) and Mann-Whitney U test (skewed distribution or variance). Receiver operating characteristic (ROC) curves were employed to evaluate the diagnostic performance. Results K values were significantly higher for malignant SPNs than for benign SPNs (0.839 ± 0.197 vs. 0.718 ± 0.120;t=2.359, P=0.023). ADC values were found to be significantly higher in benignity than malignant SPNs [(1.605 ± 0.422) × 10-3mm2/s vs. (1.278 ± 0.210) × 10-3mm2/s; t=-3.089, P=0.005). No difference was observed in Dk between the two groups (P=0.922). All parameters cannot differentiate subtypes of lung cancer. The ADC value had higher AUC (area under ROC curve) than that of K value. The sensitivity (70.8％) and accuracy (72.1％) of ADC value was higher than K value, the specificity of both methods was equal. Conclusion DKI is a feasible non-invasive tool which has comparable capability of conventional DWI in SPNs differentiation, although with lower sensitivity and accuracy. DKI can provide additional information for SPNs characterization and has a potential to be a robust way in SPNs interpretation.
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Objective To study the diagnostic value of non-contrast T1mapping in left ventricular hypertrophy(LVH).Methods Forty LVH patients(LVH group)including 11 cardiac amyloidosis(CA),19 hypertrophic cardiomyopathy (HCM) and 10 hypertensive heart disease (HHD) patients, and 14 healthy volunteers (control group) were enrolled in this retrospective study between November 2015 and October 2016.All subjects underwent cardiac magnetic resonance(CMR)on a 3 T scanner.The CMR scan protocol included cine sequences, first-pass perfusion, late Gadolinium enhancement (LGE) and non-contrast T1 mapping(MOLLI)prototype sequences.The cardiac morphology was assessed by cine,first-pass perfusion as well as LGE.Left-ventricular end-diastolic wall thickness(EDTH)was assessed for 16 segments,native T1 values were measured in hypertrophic segments. The differences in EDTH and native T1values between LVH group and control group were evaluated using t test. The ANOVA and LSD were used in the comparison of differences among four sub-groups.Sensitivity,specificity,cut-off values and area under the curve (AUC) were derived using receiver-operating characteristics curve (ROC) analysis. Results The EDTH and native T1values in LVH group were significantly higher than those of control group[(16.5±5.2)mm vs.(6.3±1.8)mm,(1 388.6±119.8)ms vs.(1 248.4±58.1)ms,t=28.8 16.4,both P<0.01].Moreover,CA showed significantly higher T1value [(1 495.5 ± 100.9)ms] than that of HCM [(1 342.0 ± 69.2)ms] and HDD [(1 290.7±45.5)ms](F=300.5,P<0.01),and T1values in HCM were also higher than HDD(P<0.01).HCM showed significantly higher EDTH than that of CA and HDD (P<0.01), and EDTH in CA was also higher than HDD (P<0.01). The native T1showed good diagnostic performance between CA and HCM with AUC 0.914,sensitivity 90.1%%,and specificity 84.3%,and cutoff value 1 382.8 ms,between CA and HHD with AUC 0.989,sensitivity 97.0%,specificity 93.5% and cutoff value 1 359.5 ms.Conclusion The elevated native T1values were useful for quantitatively differential diagnosis of LVH.
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Objective To discuss MRI and pathological features of intracranial hemangioblastoma.Methods MRIdata of 26 cases of hemangioblastoma confirmed with operation and pathology were analyzed retrospectively.Results There were 22 cases with single lesion and multiple lesions in 4 eases.And a total of 31 lesions located in the posterior cranial fossa,including 14 lesions in right cerebellar hemispheres,9 lesions in left cerebellar hemispheres,2 lesions in cerebellar inferior vermis,4 lesions in medulla oblongata,and 2 lesions in fourth ventricle.Ninteen lesions showed cystic nodular type,1 lesion was cystic type,11 lesions showed parenchymal type or partial parenchyma type.Cystic lesions showed long T1 and long T2 signal,T1WI of solid area showed slightly long T1 and slightly long T2 signal,of which 12 lesions were slightly shorter T1 signal.Solid areas significantly enhanced,cystic area had no enhancement,but cystic wall of 3 cystic nodular lesions were slightly enhanced.DWI of solid areas showed low signal.MRS showed the peak of Cho obviously increased,and the peaks of Cr and NAA obviously decreased or nearly disappeared,and the high peak of lipids and lactate were observed.Conclusion The conventional and functional MRI of intracranial hemangioblastoma have some characteristics,MRI has a great value in the diagnosis and localization of intracranial hemangioblastoma.
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Objective To discuss MRI and pathological features of intracranial hemangioblastoma.Methods MRIdata of 26 cases of hemangioblastoma confirmed with operation and pathology were analyzed retrospectively.Results There were 22 cases with single lesion and multiple lesions in 4 eases.And a total of 31 lesions located in the posterior cranial fossa,including 14 lesions in right cerebellar hemispheres,9 lesions in left cerebellar hemispheres,2 lesions in cerebellar inferior vermis,4 lesions in medulla oblongata,and 2 lesions in fourth ventricle.Ninteen lesions showed cystic nodular type,1 lesion was cystic type,11 lesions showed parenchymal type or partial parenchyma type.Cystic lesions showed long T1 and long T2 signal,T1WI of solid area showed slightly long T1 and slightly long T2 signal,of which 12 lesions were slightly shorter T1 signal.Solid areas significantly enhanced,cystic area had no enhancement,but cystic wall of 3 cystic nodular lesions were slightly enhanced.DWI of solid areas showed low signal.MRS showed the peak of Cho obviously increased,and the peaks of Cr and NAA obviously decreased or nearly disappeared,and the high peak of lipids and lactate were observed.Conclusion The conventional and functional MRI of intracranial hemangioblastoma have some characteristics,MRI has a great value in the diagnosis and localization of intracranial hemangioblastoma.
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Objective To observe the therapeutic effects of medicated thread moxibustion of traditional Zhuang nationality medicine combined with Shugan Jianpi Decoction for cirrhosis ascites. Methods Sixty patients with cirrhosis ascites were randomly divided into observation group and control group by random number method, 30 cases in each group. The treatment group received medicated thread moxibustion of traditional Zhuang nationality medicine combined with Shugan Jianpi Decoction and regular Western medicine; while control group only received regular Western medicine. Two weeks was a course of treatment. The liver function (ALT, AST, TBIL, ALB, A/G), ascites integral changes and improving time of main clinical symptoms (abdominal distension, pain, anorexia, fatigue) were observed. The clinical curative effects of two groups were evaluated with 3 months of follow-up. Results The liver function (ALT, AST, TBIL, ALB, A/G) in the treatment group after treatment was significantly improved, and the ascites integral decreased, which was better than the control group, with statistical significance (P<0.05). The improving time of main clinical symptoms in the treatment group was significantly shorter than the control group (P<0.05);The clinical effective rate was 90.00%(27/30) in the treatment group and 76.67% (23/30) in the control group, with statistical significance (P<0.05). Conclusion Medicated thread moxibustion of traditional Zhuang nationality medicine combined with Shugan Jianpi Decoction has good efficacy for cirrhosis ascites.
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Objective To preliminarily investigate the feasibility of MRI-T2* map in evaluating myocardial iron load of myocardial iron overload rabbit models.Methods Eleven rabbits were included in this study and divided into two groups,myocardial iron overload group (n =10) and the control group (n =1).Iron dextrin (dose of 50 mg/kg) was injected in muscles of thigh once a week,totally 12 weeks.Serum iron test and MRI examination were performed before iron injection,and 1 week to 12 weeks after iron injection.MRI scan protocol included short axial T2* map of the left ventricle and cross-section T2* map of the liver.T2* and R2* of the heart and the liver were measured.One rabbit was killed after MRI examination at pre-iron injection,1 week to 8 weeks,11 weeks and 12 weeks after iron injection,respectively.Heart and liver were avulsed to undergo in vitro MRI scan and then paraffin embedded for pathological slices.MRI scan protocol and measurements of the heart and the liver samples were the same to that of in vivo ones.Pearson correlation was used to calculate the relationships between the parameters.Results Myocardial T2* [(32.5 ± 8.3 ms)] and R2* values [(38.4 ± 7.9) Hz] had significant correlation with injecting iron content(1 033.2 ± 673.4 mg),the Pearson coefficients were-0.799 (P =0.001) and 0.770 (P =0.002),respectively.Myocardial T2 had no significant correlation with liver T2* values (r =0.556,P =0.070).T2* values of heart and liver in vivo [(32.5 ± 8.3) ms and (8.8 ± 5.4) ms],respectively had strong correlation with those in vitro [(19.4 ± 6.5) ms and (9.8 ± 5.0) ms],respectively (r =0.757,P =0.007 and r=0.861,P=0.001).T2* and R2* values of the heart and the liver in vivo and in vitro had no significant correlations with serum iron (P ＞ 0.05).On Prussian blue staining slices,blue particles of myocardium,sinus hepaticus and hepatocyte increased with injecting iron content.Conclusions It is feasible for MRI-T2* map to evaluate the myocardial iron load noninvasively.It may provide reliable information for detecting myocardial iron overload in patients with iron overload at an early stage.
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Objective To investigate the feasibility of ADC values in the evaluation of normal fetal brain development by measuring ADC values changes in specific regions with advancing gestational age.Methods Forty fetuses(gestational age:24 to 41 weeks) with normal brain underwent DWI(b value were 0 and 600 s/mm2).ADC values of the frontal white matter(WM),occipital WM,thalamus,basal ganglia,and cerebellum were measured by post-processing software.The differences among different regions' ADC values were calculated by repeated measurements of ANOVA,and simple linear regression was used to evaluate the relationship between ADC values and gestational age.Results The mean ADC valuesof 40 fetuses were(1 800±214) ×10-6mm2/s in frontal WM,(1 400±100) ×10-6mm2/s in basal ganglia,(1 300±126) ×10-6mm2/s in thalamus,(1 700±133) ×10-6mm2/s in occipital WM and(1 400± 155) × 10-6mm2/s in cerebellum,respectively.There was significant difference in the ADC values among the five regions(F=80.813,P＜0.01).In pair-wise comparison,ADC values of basal ganglia,thalamus and cerebellum had no significant difference; however,others had significant difference between each other.With the increasing gestational age,ADC values of basal ganglia,thalamus,occipital WM and cerebellum decreased,and had significant negative correlations with gestational age(Pearson correlation coefficient were-0.568,-0.716,-0.830 and-0.700,respectively,all P＜0.01).In terms of ADC value,occipital WM declined fastest with gestational age,followed by cerebellum and thalamus,and the slowest was basal ganglia.Frontal ADC values showed no correlation with gestational age(P＞0.05).Conclusions Specific regions of fetal brain have specific ADC values,and ADC values of the region undergo regular change with advancing gestational age.ADC value is a specific quantitative parameter that could help to evaluate normal brain development and early diagnosis of fetal brain lesions.
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Objective To evaluate the activation of the visual cortex in patients with primary openangle glaucoma (POAG) and to explore whether the neuronal activity corresponds with retinal nerve fiber layer (RNFL) and cup-to-disc (C/D) values.Methods Twenty-five patients and 25 gender-and agematched healthy volunteers were studied.Blood oxygenation level-dependent functional magnetic resonance imaging (BOLD-fMRI) and three-dimensional brain volume imaging (3 D BRAVO) sequences were obtained using 3 T MR imaging system.A full-screen black-white shift checkerboard was used for visual stimulus during the fMRI experiment and was performed on each eye of all subjects using a visual-acoustical system.All acquired data were postprocessed and analyzed by statistical parametric mapping (SPM).After analysis,individual activated mapping,intra-group mean activated mapping,and inter-group variant mapping were observed.The voxel number,intensity,and Montreal Neurological Institute (MNI) coordinate of the activated clusters were recorded.The Xjviewer software was utilized to obtain activated voxel numbers in occipital lobe.A Pearson correlated test was performed to test the correlation between the number of activated voxels and RNFL,C/D and Hodapp-Anderson-Parrish (HAP) clinical stage.Results Intra-group mean activated mappings of both patients and volunteers showed obvious activation in bilateral occipital lobes.As compared with healthy volunteers,the POAG patients exhibited statistically significantly decreased activation in bilateral occipital lobes,left hippocampus,and left cerebellum,along with lower mean RNFL [(71.56 ±21.54) i m versus (111.88 ± 9.96) μm] and higher C/D values (0.71 ± 0.18 versus 0.36 ± 0.08 ; t value was respectively-10.901 and 11.643,P ＜ 0.05).The number of activated voxels in the occipital lobes of POAG patients did not correlate with RNFL,C/D and HAP clinical stage of the corresponding eye (r value was respectively 0.157,-0.113 and-0.242,P ＞ 0.05).Conclusions fMRI demonstrated differences in visual cortex activation in POAG patients relative to healthy volunteers,suggesting it might be a promising complementary method for diagnosing glaucoma.However,fMRI findings did not correlate with POAG extent,as measured by RNFL and C/D values.Ophthalmological examination remains to play an important role in the evaluation of open-angle glaucoma.
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ObjectiveTo observe the change of cardiac function after acute myocardial infarction (AMI) in rabbit model,and to study MRI characteristics of left ventricular remodeling (LVR).Methods Forty-five japanese white rabbits underwent chest-opening coronary artery ligation surgery to obtain rabbit myocardial infarction model The animals were scanned on a 1.5 T MR scanner ( GE Healthcare,Chalfont St.Giles,UK) at six time-points as surgery,1,2,4,6,8 weeks after surgery. Cardiac function parameters were measured,including left ventricular end diastolic volume ( EDV ),stroke volume ( SV ),ejection fraction (EF),peak ejection rate ( PER ) and peak firing rate (PFR).At each time point,5 rabbits were randomly selected and performed re-thoracotomy to obtain heart specimen.Each specimen was examined by MRI with the diffusion tensor imaging ( DTI ).The value of ADC and fractional anisotropy (FA) were collected. Cardiac function data sets of different time points were analyzed using repeated measures data of ANOVA.The FA and ADC values of infarction myocardium set of different time points or different parts of the myocardium were analyzed using one-way ANOVA. The average was compared statistically between two adjacent groups using LSD-t test. Results Left ventricular EDV increased in progress with the time.It was increased from ( 2.21 ± 0.35 ) ml preoperatively to ( 3.15 ± 0.57 ) ml 8-week postoperatively.But the difference was not statistical significant ( F =1.384,P =0.220).EF was decreased from(57.31 ± 11.11 )％ to( 34.71 ± 8.72 )％.It dropped significantly and the difference was statistically significant (F =27.134,P =0.001 ).EF showed a downward trend with the increase of EDV.By linear regression analysis,an equation was set up with y =- 5.58x + 57.7 ( F =8.855,P =0.005 ).On the other hand,PER showed a progressive decline from (27.31 ± 13.06) ml/s to ( 17.31 ± 6.41 ) ml/s ( F =2.105,P =0.037 ),and PFR decreased from ( 23.79 ± 14.15 ) ml/s to ( 12.07 ± 6.91 ) ml/s ( F =2.366,P =0.011 ).FA value decreased from 0.442 ±0.093 to 0.107 ±0.037( F =12.61,P =0.001 ),and ADC valueshowed upward trend from (5.07 ± 1.15) ×10-4 mm2/s to(6.39 ±0.78) ×10-4 mm2/s (F=4.166,P =0.022 ).FA values of infarct,adjacent and remote region were 0.201 ± 0.049,0.316 ± 0.127 and 0.323 ± 0.117 respectively( F =3.896,P =0.004 ),and the ADC values in these regions were (6.19 ± 1.78 ) ×10 -4,(5.44 ± 2.63 ) × 1 0 -4,(5.29 ± 2.02 ) × 10 -4 mm2/s respectively ( F =3.248,P =0.018 ).FA and ADC values were significantly different between the infarct region and adjacent region ( t =7.327,P =0.001 ;t =3.292,P =0.005,respectively),but there was no significantly different between adjacent region and remote region ( t =1.024,P =0.129 ; t =1.467,P =0.164,respectively ).ConclusionsMRI measurement of parameters of cardiac function can be used to monitor the process of left ventricular function remodeling after AMI.The process of micro-structural remodeling of myocardium can be reflected by DTI.MRI provides a feasible imaging modality for LVR after AMI.
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Objective To compare the efficiency of enhanced T2* weighted angiography (ESWAN) sequence with that of a conventional T2*-weighted gradient-recalled-echo (GRE T2*WI) sequence for the detection of hemorrhagic shearing lesions in patients with diffuse axonal injury (DAI). And combined with MRI parameters, to further discuss the principles and virtues of ESWAN sequence. Methods Seventeen patients with DAI were enrolled in this study. The raw data acquired from ESWAN scan were postprocessed by using the mean square root of multi-echoes. Then, the postprocessed images were compared with the conventional GRE T2* weighted images. The global and regional (superficial, deep and posterior fossa) lesion numbers determined by both sequences were compared by using Wilcoxon signed ranks test (two-tailed). Differences were considered to be significant at P≤0.05. Results Hemorrhagic lesions were more obvious on ESWAN images than those on conventional GRE T2* weighted images. The median and range value of the detected lesion numbers on ESWAN images were 27 and (1-239) in whole brain, 13 and (1-89) in cerebral superficial region, 5 and (0-111) in cerebral deep region and 1 and (0-39) in posterior fossa region, respectively; whereas, on GRE T2* weighted images, they were 7 and (1-34) in whole brain, 5 and (1-27) in cerebral superficial region, 2 and (0-25) in cerebral deep region and 0 and (0-4) in posterior fossa region, respectively. There were significant statistical differences between the two sequences in revealing the lesions in all the four regions (Z=-3.519,-3.182,-3.185,-2.677,P＜0.05). Conclusion In ESWAN sequence, multi-echo acquisition ensured sufficient magnetic susceptibility for detecting small hemorrhagic lesions. So, ESWAN is more sensitive to small hemorrhage, which revealed more hemorrhagic lesions than conventional GRE T2*WI and presented more valuable information for the diagnosis of DAI.
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Objective To demonstrate the value of eombined application of prenatal ultrasonography with fetal magnetic resonance imaging(MRI) in the diagnosis of monochorionic muhifetal realformations. Methods Fourteen cases of muhifetal malformations,detected by prenatal ultrasonography,received MRI within 48 h afterwards.All diagnosis were confirmed after delivery or mid-term termination.All imaging results of the 14 cases were retrospectively reviewed. Results Among the 14 cases,there were 7 acardias,5 Conjoined twins and 2 demise of multifetuses.Comparing ultrasound with MRI,we found that:(1)In cases with acardia and demise of multifetusea,ultrasound could diagnose correctly and be an important tool for follow-up,while MRI could demonstrate organs and structures of the acardiac recipient more clearly and detect the secondary changes of brain in the donor and survived fetus.(2)In Conjoined twins,ultrasound was superior to MRI in demonstrating the structure and function of cardiovascular system : and equivalent to MRI in identifying stomach,kidney,bladder and limbs;but inferior to MRI in identifying esophagus,lung,liver and intestinal,especially in the brain. And MRI could demonstrate two fetuses and the relationship between them in COnjoined twins simultaneously. Conclusions Prenatal ultrasonography and MRI have their own advantages and disadvantages in diagnosing monochorionic multifetal malformations.But the combination of prenatal ultrasonography and fetal MRI may be more valuable.
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Objective To study the value of magnetic resonance diffusion tensor imaging(MR-DTI) in evaluating the severity of liver cirrhosis.Methods Seventeen patients with Child A liver fibrosis (age=35.0+11.8 years,14 males and 3 females),12 with Child B(age=44.7+14.0 years,5 males and 7 females) and 8 with Child C(age=48.7+7.6 years,3 males and 5 females) were recruited.All patients had clinical data and serum makers in full.Fifty normal controls (age=35.2+14.2,28 males and 22 females) were also recruited.Diffusion tensor imaging(DTI) was performed in all subjects using a GE Propeller HD 1.5T MR scanner by employing a spin echo single-shot EPI(echo planar imaging) sequence.Average diffusion coefficient(DCave) and fractional anisotropy(FA) maps were generated from each P articipants DTI scan using AW 4.2 functool software.All the statistic analysis was performed in SPSS 13.0 , and P value of less than 0.05 was deemed to be significant . Results DCave values were 1.54±0.25 ,1.33±0.18 ,1.02±0.12 ,0.66±0.27 in control group and Child A , B , C respectively , the FA values were 0.46±0.10, 0.42±0.08, 0.56±0.05,0.71±0.41 in control group and Child A, B, C respectively. Significantly low DCave and changed FA in liver fibrosis group were found(P< 0. 05). Among the four groups, significant differences were found in DCave values and FA values(P<0.05) except control group VS Child A group in FA values(P=0.54).Conclusion MR-DTI is relevant to the severity of liver cirrhosis, and may be a useful tool for evaluating the severity of liver cirrhosis.
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Objective To investigate clinical efficacy of the CT guided mixture Danshen injection into the periganglionic space in the treatment of lumbocrural pain.Methods Mixture Danshen infiltrations were performed in 63 patients with lumbocrural pain under CT guidance.Scores of VAS were compared at 3 and 6 months after the therapeutic procedure with evaluation of the efficacy.Results Significant pain reduction was observed in 51 patients (51/63,80.95%),with the score of VAS 7.60± 2.00 (before therapy) dropping to 3.85 ± 1.60 (after 1 month) and 4.05± 1.70 (after 6 month).Differences of VAS scores before and after the therapy were statistically significant.Differences between one-month and three-month follow-up were not statistically significant.Conclusion Mixture Danshen injection around the spinal nerve roots under CT guidance is safe and useful in the treatment of lumbocrural pain.
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To analyze MR manifestations of postoperative spinal complications and investigate the value of MRI in the diagnosis and differentiated diagnosis, 114 cases of spinal postoperative complications were analyzed retrospectively and compared with the clinical data. The results showed that the main postoperative spinal complications included spinal stenosis (n=33, consisting of 21 cases of epidural fibrosis and 12 cases of epidural hematoma or epidural abscess), lack of spinal stability (n=43), infection (n=23, consisting of 7 cases of para-spinal soft-tissue infection, 5 cases of vertebral discitis, 4 cases of vertebral and appendix infection, 3 cases of epidural abscess, 2 cases of myelitis, 2 cases of spinal arachnoiditis), others (n=28, consisting of 12 cases of inner fixation failure, 9 cases of epidural hematoma, 7 cases of cerebrospinal fluid gusher). It is concluded that MRI can specifically display all kinds of postoperative spinal complications, and is of significant value in the diagnosis and differentiated diagnosis of postoperative spinal complications.