Value of multiple models of diffusion-weighted imaging to predict hepatic lymph node metastases in colorectal liver metastases patients

BACKGROUND About 10%-31% of colorectal liver metastases(CRLM)patients would concomitantly show hepatic lymph node metastases(LNM),which was considered as sign of poor biological behavior and a relative contraindication for liver resection.Up to now,there’s still lack of reliable preoperative methods to assess the status of hepatic lymph nodes in patients with CRLM,except for pathology examination of lymph node after resection.AIM To compare the ability of mono-exponential,bi-exponential,and stretchedexponential diffusion-weighted imaging(DWI)models in distinguishing between benign and malignant hepatic lymph nodes in patients with CRLM who received neoadjuvant chemotherapy prior to surgery.METHODS In this retrospective study,97 CRLM patients with pathologically confirmed hepatic lymph node status underwent magnetic resonance imaging,including DWI with ten b values before and after chemotherapy.Various parameters,such as the apparent diffusion coefficient from the mono-exponential model,and the true diffusion coefficient,the pseudo-diffusion coefficient,and the perfusion fraction derived from the intravoxel incoherent motion model,along with distributed diffusion coefficient(DDC)andαfrom the stretched-exponential model(SEM),were measured.The parameters before and after chemotherapy were compared between positive and negative hepatic lymph node groups.A nomogram was constructed to predict the hepatic lymph node status.The reliability and agreement of the measurements were assessed using the coefficient of variation and intraclass correlation coefficient.RESULTS Multivariate analysis revealed that the pre-treatment DDC value and the short diameter of the largest lymph node after treatment were independent predictors of metastatic hepatic lymph nodes.A nomogram combining these two factors demonstrated excellent performance in distinguishing between benign and malignant lymph nodes in CRLM patients,with an area under the curve of 0.873.Furthermore,parameters from SEM showed substantial repeatability.CONCLUSION The developed nomogram,incorporating the pre-treatment DDC and the short axis of the largest lymph node,can be used to predict the presence of hepatic LNM in CRLM patients undergoing chemotherapy before surgery.This nomogram was proven to be more valuable,exhibiting superior diagnostic performance compared to quantitative parameters derived from multiple b values of DWI.The nomogram can serve as a preoperative assessment tool for determining the status of hepatic lymph nodes and aiding in the decision-making process for surgical treatment in CRLM patients.

Intravoxel incoherent motion diffusion-weighted magnetic resonance imaging for predicting histological grade of hepatocellular carcinoma:Comparison with conventional diffusion-weighted imaging

AIM To compare intravoxel incoherent motion(IVIM)-derived parameters with conventional diffusion-weighted imaging(DWI) parameters in predicting the histological grade of hepatocellular carcinoma(h CC) and to evaluate the correlation between the parameters and the histological grades.METHODS A retrospective study was performed. Sixty-two patients with surgically confirmed h CCs underwent diffusion-weighted magnetic resonance imaging with twelve b values(10-1200 s/mm^2). The apparent diffusion coefficient(ADC), pure diffusion coefficient(D), pseudo-diffusion coefficient(D*), and perfusion fraction(f) were calculated by two radiologists. The IVIM and conventional DWI parameters were compared among the different grades by using analysis of variance(ANOVA) and the Kruskal-Wallis test. Receiver operating characteristic(ROC) analysis was performed to evaluate the diagnostic efficiency of distinguishing between low-grade(grade 1, G1) and high-grade(grades 2 and 3, G2 and G3) hC C. The correlation between the parameters and the histological grades was assessed by using the Spearman correlation test. Bland-Altman analysis was used to evaluate the reproducibility of the two radiologists' measurements.RESULTS The differences in the ADC and D values among the groups with G1, G2, and G3 histological grades of HCCs were statistically significant(P < 0.001). The D* and f values had no significant differences among the different histological grades of h CC(P > 0.05). The ROC analyses demonstrated that the D and ADC values had better diagnostic performance in differentiating the low-grade h CC from the high-grade h CC, with areas under the curve(AUCs) of 0.909 and 0.843, respectively, measured by radiologist 1 and of 0.911 and 0.852, respectively, measured by radiologist 2. The following significant correlations were obtained between the ADC, D, and D~* values and the histological grades: r =-0.619(P < 0.001), r =-0.628(P < 0.001), and r =-0.299(P = 0.018), respectively, as measured by radiologist 1; r =-0.622(P < 0.001), r =-0.633(P < 0.001), and r =-0.303(P = 0.017), respectively, as measured by radiologist 2. The intra-class correlation coefficient(ICC) values between the two observers were 0.996 for ADC, 0.997 for D, 0.996 for D*, and 0.992 for f values, which indicated excellent interobserver agreement in the measurements between the two observers.CONCLUSION The IVIM-derived D and ADC values show better diagnostic performance in differentiating high-grade hC C from low-grade hC C, and there is a moderate to good correlation between the ADC and D values and the histological grades.

Liver intravoxel incoherent motion diffusion-weighted imaging for the assessment of hepatic steatosis and fibrosis in children

AIM To evaluate the correlation between intravoxel incoherent motion(IVIM) diffusion-weighted imaging(DWI) parameters and the degree of hepatic steatosis and fibrosis in children.METHODS This retrospective study was approved by the institutional review board. The children(≤ 18 years) who underwent liver IVIM DWI with 8 b-values under the suspicion of hepatic steatosis or fibrosis from February 2013 to November 2016 were included. Subjects were divided into normal, fatty liver(FAT), and fibrotic liver(FIB) groups. The slow diffusion coefficient(D), fast diffusion coefficient(D*), perfusion fraction(f), and apparent diffusion coefficient(ADC) were measured. MR proton density fat fraction(PDFF), MR elastography(MRE), and IVIM values were compared.RESULTS A total of 123 children(median age of 12 years old, range: 6-18 years) were included, with 8 in the normal group, 93 in the FAT group, and 22 in the FIB group. The D* values were lower in the FIB group compared with those of the normal(P = 0.015) and FAT(P = 0.003) groups. The f values were lower in the FIB group compared with the FAT group(P = 0.001). In multivariate analyses, PDFF value was positively correlated with f value(β = 3.194, P < 0.001), and MRE value was negatively correlated with D* value(β =-7.031, P = 0.032). The D and ADC values were not influenced by PDFF or MRE value.CONCLUSION In liver IVIM DWI with multiple b-values in children, there was a positive correlation between hepatic fat and blood volume, and a negative correlation between hepatic stiffness and endovascular blood flow velocity, while diffusion-related parameters were not affected.

Intravoxel Incoherent Motion Diffusion Weighted Imaging for the Therapeutic Response of Transarterial Chemoembolization for Hepatocellular Carcinoma

Background: Intravoxel incoherent motion diffusion weighted imaging (IVIM-DWI) can not only observe the diffusion of tissue water molecules but also reflect the blood perfusion information of tissue microcirculation. IVIM-DWI has been applied in many clinical areas. However, few studies have addressed the use of IVIM-DWI for the evaluation of transarterial chemoembolization (TACE) response in hepatocellular carcinoma (HCC) patients. Objectives: The purpose of the present study was to explore the role of IVIM-DWI for the therapeutic response of TACE for HCC. Materials and Methods: Twenty patients underwent IVIM-DWI scan on a 3.0T magnetic resonance imaging instrument 1 - 3 days before and 30 to 40 days after TACE. The values of IVIM-DWI parameters, including standard apparent diffusion coefficient (ADC), pure diffusion coefficient (Dslow), pseudo-diffusion coefficient (Dfast) and perfusion fraction (f) were measured. The values of IVIM-DWI parameters before and after TACE were compared using paired t tests. The values between responsive and non-responsive groups were compared using independent-samples t test. P 0.05 indicated statistical significance. Results: After TACE, the ADC and Dslow values in the tumors increased significantly, and the values of Dfast decreased significantly, while the values of f value did not change obviously. The ADC values in responsive group were remarkably higher than those in non-responsive group, the Dfast values in responsive group were significantly lower than those in non-responsive group, but the values of Dslow and f between the two groups were not different significantly. Conclusions: IVIM-DWI parameters can be used as potential markers for the therapeutic response of TACE for HCC.

Application Progress of Intravoxel Incoherent Motion Diffusion Weighted Magnetic Resonance Imaging in Pancreatic Cancer

Intravoxel incoherent motion imaging (IVIM), on the traditional diffusion weighted imaging (DWI) technology, uses the biexponential model and adopts the multi-b-value analysis to obtain the perfusion information of water molecule diffusion and microcirculation without the use of contrast agent. It is more and more used in pancreatic diseases, which is of great significance for the diagnosis and identification of pancreatic cancer. This article will review the principles of IVIM imaging and its application in pancreatic diseases, especially in pancreatic cancer diagnosis, the prediction of pathological grade of pancreatic ductal adenocarcinoma, the judgment of lymph node metastasis, and differentiation of pathological classification.

Chemotherapy response evaluation in a mouse model of gastric cancer using intravoxel incoherent motion diffusionweighted MRI and histopathology

AIM To determine the role of intravoxel incoherent motion(IVIM) diffusion-weighted(DW) magnetic resonance imaging(MRI) using a bi-exponential model in chemotherapy response evaluation in a gastric cancer mouse model.METHODS Mice bearing MKN-45 human gastric adenocarcinoma xenografts were divided into four treated groups(TG1, 2, 3 and 4, n = 5 in each group) which received Fluorouracil and Calcium Folinate and a control group(CG, n = 7). DW-MRI scans with 14 b-values(0-1500 s/mm2) were performed before and after treatment on days 3, 7, 14 and 21. Fast diffusion component(presumably pseudo-perfusion) parameters including the fast diffusion coefficient(D*) and fraction volume(f p), slow diffusion coefficient(D) and the conventional apparent diffusion coefficients(ADC) were calculated by fitting the IVIM model to the measured DW signals. The median changes from the baseline to each posttreatment time point for each measurement(ΔADC, ΔD* and Δf p) were calculated. The differences in the median changes between the two groups were compared using the mixed linear regression model by the restricted maximum likelihood method shown as z values. Histopathological analyses including Ki-67, CD31, TUNEL and H&E were conducted in conjunction with the MRI scans. The median percentage changes were compared with the histopathological analyses between the pre-and post-treatment for each measurement.RESULTS Compared with the control group, D* in the treated group decreased significantly(ΔD*treated% =-30%,-34% and-20%, with z =-5.40,-4.18 and-1.95. P = 0.0001, 0.0001 and 0.0244) and f p increased significantly(Δfptreated% = 93%, 113% and 181%, with z = 4.63, 5.52, and 2.12, P = 0.001, 0.0001 and 0.0336) on day 3, 7 and 14, respectively. Increases in ADC in the treated group were higher than those in the control group on days 3 and 14(z = 2.44 and 2.40, P = 0.0147 and P = 0.0164). CONCLUSION Fast diffusion measurements derived from the biexponential IVIM model may be more sensitive imaging biomarkers than ADC to assess chemotherapy response in gastric adenocarcinoma.

Updates in advanced diffusion-weighted magnetic resonance imaging techniques in the evaluation of prostate cancer

Diffusion-weighted magnetic resonance imaging(DWMRI) is considered part of the standard imaging protocol for the evaluation of patients with prostate cancer.It has been proven valuable as a functional tool for qualitative and quantitative analysis of prostate cancer beyond anatomical MRI sequences such as T2-weighted imaging. This review discusses ongoing controversies in DW-MRI acquisition, including the optimal number of b-values to be used for prostate DWI, and summarizes the current literature on the use of advanced DWMRI techniques. These include intravoxel incoherent motion imaging, which better accounts for the nonmono-exponential behavior of the apparent diffusion coefficient as a function of b-value and the influence of perfusion at low b-values. Another technique is diffusion kurtosis imaging(DKI). Metrics from DKI reflect excess kurtosis of tissues, representing its deviation from Gaussian diffusion behavior. Preliminary results suggest that DKI findings may have more value than findings from conventional DW-MRI for the assessment of prostate cancer.

Value of intravoxel incoherent motion in detecting and staging liver fibrosis: A meta-analysis

BACKGROUND Liver fibrosis(LF) is a common pathological feature of all chronic liver diseases.With the accumulation of extracellular matrix in the fibrotic liver, true molecular water diffusion and perfusion-related diffusion are restricted. Intravoxel incoherent motion(IVIM) can capture the information on tissue diffusivity and microcapillary perfusion separately and reflect the fibrotic severity with diffusion coefficients.AIM To investigate the diagnostic performance of IVIM in detecting and staging LF with histology as a reference standard.METHODS A comprehensive literature search was conducted to identify studies on the diagnostic accuracy of IVIM for assessment of histologically proven LF. The stages of LF were classified as F0(no fibrosis), F1(portal fibrosis without septa),F2(periportal fibrosis with few septa), F3(septal fibrosis), and F4(cirrhosis)according to histopathological findings. Data were extracted to calculate the pooled sensitivity, specificity, positive and negative likelihood ratios, and diagnostic odds ratio, as well as the area under the summary receiver operating characteristic curve(AUC) in each group.RESULTS A total of 12 studies with 923 subjects were included in this meta-analysis with 5 studies(n = 465) for LF ≥ F1, 9 studies(n = 757) for LF ≥ F2, 4 studies(n = 413) for LF ≥ F3, and 6 studies(n = 562) for LF = F4. The pooled sensitivity and specificity were estimated to be 0.78(95% confidence interval: 0.73-0.82) and 0.81(0.74-0.86)for LF ≥ F1 detection with IVIM;0.82(0.79-0.86) and 0.80(0.75-0.84) for staging F2 fibrosis;0.85(0.79-0.90) and 0.83(0.77-0.87) for staging F3 fibrosis, and 0.90(0.84-0.94) and 0.75(0.70-0.79) for detecting F4 cirrhosis, respectively. The AUCs for LF≥ F1, F2, F3, F4 detection were 0.862(0.811-0.914), 0.883(0.856-0.909), 0.886(0.865-0.907), and 0.899(0.866-0.932), respectively. Moderate to substantial heterogeneity was observed with inconsistency index(I2) ranging from 0% to 77.9%. No publication bias was detected.CONCLUSION IVIM is a noninvasive tool with good diagnostic performance in detecting and staging LF. Optimized and standardized IVIM protocols are needed to further improve its diagnostic accuracy in clinical practice.

Assessing the Early Response of Advanced Cervical Cancer to Neoadjuvant Chemotherapy Using Intravoxel Incoherent Motion Diffusion-weighted Magnetic Resonance Imaging： A Pilot Study

Background： Diffusion-weighted imaging （DWI） with the intravoxel incoherent motion （IVIM） model has shown promising results for providing both diffusion and perfusion intbrmation in cervical cancer; however, its use to predict and monitor the efficacy ofneoadjuvant chemotherapy （NACT） in cervical cancer is relatively rare. The study aimed to evaluate the use of DWl with 1VIM and monoexponential models to predict and monitor the efficacy of NACT in cervical cancer. Methods： Forty-two patients with primary cervical cancer underwent magnetic resonance exams at 3 time points （pre-NACT, 3 weeks after the first NACT cycle, and 3 weeks after the second NACT cycle）. The response to treatment was determined according to the response evaluation criteria in solid tumors 3 weeks after the second NACT treatment, and the subjects were classified as two groups： responders and nonresponders groups. The apparent diffusion coefficient （ADC）, true diffusion coefficient （D）, perfusion-related pseudo-diffusion coefficient （D＊）, and perfusion fraction （f） values were determined. The differences in IVlM-derived variables and ADC between the different groups at the different time points were calculated using an independent samples t-test. Results： The D and ADC values were all significantly higher for the responders than tbr the nonresponders at all 3 time points, but no significant differences were observed in the D＊ and fvalues. An analysis of the receiver operating characteristic （ROC） curves indicated that a D value threshold 〈0.93 × 10 3 mm2/s and an ADC threshold 〈1.11× 10 3 mm2/s could differentiate responders from nonresponders at pre-NACT time point, yielding area under the curve （AUC） of which were 0.771 and 0.806, respectively. The ROC indicated that the AUCs of D and ADC at the 3 weeks after the first NACT cycle and 3 weeks after the second NACT cycle were 0.823, 0.763, and 0.787, 0.794, respectively. The AUC values of D and ADC at these 3 time points were not significantly different （P = 0.641, 0.512, and 0.547, respectively）. Conclusions： D and ADC values may be useful for predicting and monitoring the efficacy of NACT in cervical cancer. An IVIM model may be equal to monoexponential model in predicting and monitoring the efficacy of NACT in cervical cancer.

Evaluation Value of Intravoxel Incoherent Motion Diffusion-Weighted Imaging on Early Efficacy of Magnetic Resonance-Guided High-Intensity Focused Ultrasound Ablation for Uterine Adenomyoma

To investigate the evaluation value of intravoxel incoherent motion diffusion-weighted imaging(IVIM-DWI)on the early efficacy of magnetic resonance-guided high-intensity focused ultrasound(MRgFUS)ablation for uterine adenomyoma.The clinical and magnetic resonance imaging(MRI)data of 36 patients with uterine adenomyoma before and after MRgFUS treatment in our hospital from January 2018 to December 2018 were retrospectively analyzed.All the 36 patients underwent MRI examination one day before operation and immediately after operation using GE Discovery MR7503.0T MRI,including conventional sequences(T1WI,T2WI,and T2 fat suppression sequences)plain scan,IVIM-DWI sequences with 9 b values,and contrast enhanced-MRI sequences.The IVIM-DWI quantitative parameters(true diffusion coefficient D,perfusion related diffusion coefficient D*,and perfusion fraction f)of double-exponential model were obtained by using GE ADW 4.7 functool,a postprocessor.SPSS 24.0 software was used to analyze the difference in parameter between the ablation and non-ablation areas of uterine adenomyoma.DWI signal in the ablation area of uterine adenomyoma was increased,and manifested as heterogeneous diffuse high signal,with low central signal and high edge signal.Values of D,D*and f in the ablation area of uterine adenomyoma were significantly lower than those in the non-ablation area,and there was statistical difference between the two(P<0.05).The areas under receiver operating characteristic(ROC)curve of D,D*and f values in the ablation area of uterine adenomyoma were 0.854,0.898 and 0.924,respectively;the optimal thresholds for the diagnosis of ablation area of uterine adenomyoma were 0.81×10−3 mm2/s,4.99×10−3 mm2/s and 0.24,respectively;the diagnostic sensitivity was 80.6%,72.2%and 94.4%,respectively;and the specificity was 91.7%,97.2%and 94.4%,respectively.IVIM-DWI has a certain clinical value in the evaluation on early efficacy of MRgFUS ablation of uterine adenomyosis.

DCE-MRI和IVIM-DWI评估直肠癌微血管含量的比较研究

目的:探讨动态对比增强磁共振成像(dynamic contrast-enhanced magnetic resonance imaging,DCE-MRI)和体素内不相干运动弥散加权成像(intravoxel incoherent motion diffusion-weighted imaging,IVIM-DWI)在评估直肠癌微血管含量中的差异。方法:研究2019年12月—2022年12月上海中医药大学附属曙光医院经病理学检查诊断为直肠腺癌并行IVIMDWI和DCE-MRI扫描的患者23例。Tofts模型计算DCE-MRI参数为容积分数(volume fraction,V_(e))、容量转移常数(space transport coefficient,K^(trans))和速率常数(rate constant,K_(ep))。IVIM-DWI参数:单纯弥散系数(simple diffusion coefficient,D),灌注相关弥散系数(perfusion related diffusion coefficient,D^(*)),灌注分数(perfusion fraction,f),通过计算双指数模型得到。对与直肠癌微血管含量相关的DCE-MRI和IVIM-DWI定量参数进行分析比较。结果:不同病理学分级的直肠癌K^(trans)和D差异有统计学意义(F=9.159,P=0.002;F=5.106,P=0.016)。在评估直肠癌病理学分级时,K^(trans)优于D。灌注参数K^(trans),K_(ep)和D^(*)与直肠癌微血管含量呈显著正相关(r=0.734,P<0.001;r=0.617,P=0.002;r=0.456,P=0.029)。其中DCE-MRI定量参数评估直肠癌微血管含量优于IVIM-DWI定量参数。结论:与IVIM-DWI相比,DCE-MRI评价直肠癌分化程度和微循状态方面效能更佳。但是考虑到IVIM-DWI不需要注射对比剂,IVIM-DWI仍然可以被推荐用于直肠癌分化程度和微循环状态。

IVIM-DWI基于肝段水平对肝纤维化患者测量的可重复性及诊断效能

目的评估肝纤维化患者应用体素内不相干运动扩散加权成像(IVIM-DWI)测量的可重复性,并评估基于肝右叶肝段的IVIM-DWI相关参数对早期及中晚期肝纤维化的诊断效能。方法2020年6月~2022年9月期间招募早期肝纤维化及晚期肝纤维化患者,使用IVIM-DWI序列进行肝脏扫描。两名检查者基于肝右叶各段水平,应用单指数模型、双指数模型和拉伸指数模型测量相关参数数据。对获得的测量数据应用变异系数(CV)进行可重复性检验,剔除可重复性较低(CV>20%)的肝段参数后,用Logistic回归分析最终纳入的IVIM-DWI参数,计算诊断效能并描绘ROC曲线。结果59名早期肝纤维化和38名晚期肝纤维化患者被纳入研究。获得的数据中,D*(CV:29.25%~41.47%)和DDC(CV:22.44%~30.63%)的可重复性较差,而ADC(CV:5.29%~9.76%)、D(9.53%~13.22%)、f(CV:12.83%~16.95%)和α(CV:8.82%~15.52%)的可重复性较好。剔除可重复性较低的参数后,Logistic回归分析建立早期肝纤维化与晚期肝纤维化组的诊断模型并描绘ROC曲线,最终纳入模型的肝段水平参数为SⅦD及SⅧf,最终回归模型的曲线下面积(AUC)为0.857。结论基于肝段的高可重复性,IVIM-DWI对肝纤维化仍能获得较好的诊断效能,其中D、f参数以及肝右叶上段SⅦ、SⅧ在满足可重复性的前提下,可能是较稳定的肝纤维化分级诊断因素。

IVIM-DWI及多层螺旋CT与肝细胞肝癌微血管侵犯的相关性分析

目的探究体素内不相干运动扩散加权成像(IVIM-DWI)多层螺旋CT(MSCT)与肝细胞肝癌(HCC)微血管侵犯(MVI)的相关性分析。方法选取2019年12月至2022年12月本院收治HCC患者100例临床资料开展回顾性分析。所有患者均经过病理检查、VIM-DWI检查与MSCT检查。100例患者经手术病理确诊为MVI阳性38例,MVI阴性62例。比较两组IVIM-DWI、MSCT定性、定量参数分析的差异,并通过ROC曲线分析IVIM-DWI定量参数、MSCT定量参数及联合数据对HCC存在MVI的诊断价值。结果MVI阳性组边缘毛糙、瘤周低信号、瘤周强化、存在晕征高于MVI阴性组(P<0.05),肿瘤包膜低于MVI阴性组(P<0.05)。两组D、F比较差异无统计学意义(P>0.05),但MVI阳性组ADC、D低于MVI阴性组(P<0.05)。MVI阳性组动脉期CT值低于MVI阴性组(P<0.05),延迟期CT值、门静脉期CT值、肿瘤大小高于MVI阴性组(P<0.05)。ROC曲线分析显示,ADC、D、D、f、延迟期CT值、门静脉期CT值、动脉期CT值、肿瘤大小诊断HCC存在MVI的AUC分别为0.775、0.856、0.609、0.565、0.708、0.728、0.643、0.705。MSCT参数、IVIM-DWI参数、联合数据诊断HCC存在MVI的AUC分别为0.809、0.832、0.920,均具有较好准确性。结论IVIM-DWI、MSCT定性、定量参数均与HCC患者MVI相关,而IVIMDWI、MSCT诊断MVI均具有一定价值,且联合诊断准确性更高。

磁共振增强T1 mapping和IVIM-DWI技术评估乙型肝炎肝硬化患者肝脏储备功能价值研究

目的分析应用磁共振(MR)体素内不相干运动扩散加权成像(IVIM-DWI)和钆塞酸二钠增强T1 mapping参数评估乙型肝炎肝硬化患者肝脏储备功能的价值。方法2020年3月~2022年3月我院诊治的乙型肝炎肝硬化患者60例,接受吲哚菁绿15 min滞留率检测和MR增强扫描,测量增强前20 min和增强后20 min T1弛豫时间,计算肝细胞增强分数,并应用Mltalytics 1.0.1软件自动测算表观扩散系数(ADC)和真性水分子扩散系数(D)。应用受试者工作特征(ROC)曲线分析参数评估肝储备的效能。结果在60例肝硬化患者中,吲哚菁绿15 min滞留率<10%者30例(A组),≥10%但<30%者16例(B组),≥30%者14例(C组);C组增强前T1弛豫时间和增强后T1弛豫时间分别为(700.5±71.2)ms和(324.1±99.6)ms,显著长于A组【分别为(612.2±28.3)ms和(148.3±51.9)ms,P<0.05】或B组【分别为(682.5±73.1)ms和(256.2±88.1)ms,P<0.05】,而ADC、D和肝细胞增强分数分别为(0.5±0.1)×10^(3)、(0.5±0.1)×10^(3)和(50.2±11.6)%,均显著低于A组【分别为(1.2±0.1)×10^(3)、(1.0±0.4)×10^(3)和(80.8±10.9)%,P<0.05】或B组【分别为(0.8±0.2)×10^(3)、(0.7±0.2)×10^(3)和(59.4±19.7)%,P<0.05】;ROC曲线分析显示,增强前和增强后20 min T1弛豫时间、ADC、D和肝细胞增强分数评估乙型肝炎肝硬化患者肝脏储备功能均具有较高的价值(灵敏度均在70.0%以上,特异度均在76.7%以上)。结论应用MR IVIM-DWI和T1 mapping参数评估乙型肝炎肝硬化患者肝脏储备功能具有很大的临床价值,可为临床决策提供影像学依据。

HRMRI联合IVIM-DWI对直肠癌壁外血管侵犯的诊断价值分析

目的探究高分辨率磁共振成像(HRMRI)联合体素内不相干运动扩散加权成像(IVIM-DWI)对直肠癌壁外血管侵犯(EMVI)的诊断价值。方法选取2020年5月至2023年5月我院收治的直肠癌患者82例,术前均进行HRMRI联合IVIM-DWI检查,根据术后病理检查结果,观察患者EMVI评分情况,将患者分为EMVI组和非EMVI组,比较两组IVIM-DWI相关参数[快弥散系数(D)和灌注分数(f)]差异,分析HRMRI、IVIM-DWI单独及联合应用对EMVI的诊断价值。结果82例直肠癌患者中,EMVI评分3分、4分的数量分别为19例(23.17%)和13例(15.85%);术后病理结果显示,82例直肠癌患者中有37例(45.12%)出现EMVI,EMVI组患者D、f均高于与非EMVI组患者(P<0.05);HRMRI、IVIM-DWI单独诊断EMVI阳性患者分别为32例(39.02%)、41例(50.00%),联合诊断EMVI阳性患者48例(58.54%);HRMRI、IVIM-DWI单独诊断EMVI的灵敏度分别为67.56%、75.68%,特异度分别为84.44%、71.11%,联合诊断灵敏度为91.89%,特异度为68.88%,Kappa一致性分析结果显示,HRMRI、IVIM-DWI单独、联合诊断EMVI的kappa值分别为0.526、0.463、0.592。结论HRMRI、IVIM-DWI均对直肠癌患者EMVI的诊断具有一定诊断价值,二者联合应用诊断效能更高,值得推广应用。

IVIM-DWI参数联合DCE-MRI参数对肝癌患者经肝动脉化疗栓塞治疗后复发的预测价值

目的探讨体素内不相关运动扩散加权成像(IVIM-DWI)参数联合磁共振动态对比增强(DCE-MRI)参数对肝癌患者经肝动脉化疗栓塞(TACE)治疗后复发的预测价值。方法160例经TACE治疗有效的肝癌患者根据复发情况分为复发组和未复发组,比较两组的IVIM-DWI参数(D、D^(*)、ADC)、DCE-MRI参数(K_(trans)、K_(ep)、V_(e)),分析相关参数对肝癌患者TACE治疗后复发的预测价值。结果复发组的D低于未复发组,D^(*)、K_(trans)、K_(ep)均高于未复发组(P<0.05);两组的ADC、V_(e)比较,差异无统计学意义(P>0.05)。ROC曲线显示,D^(*)、D、K_(trans)、K_(ep)联合对肝癌患者TACE治疗后复发具有良好的预测价值(AUC=0.814)。结论IVIM-DWI参数联合DCE-MRI参数可有效预测肝癌患者TACE治疗后的复发情况。

IVIM-DWI与DCE-MRI在良性前列腺增生和前列腺癌鉴别诊断中的应用

目的观察体素内不相干运动磁共振加权成像(IVIM-DWI)与动态增强磁共振成像(DCE-MRI)对良性前列腺增生和前列腺癌的鉴别诊断意义。方法回顾性分析经病理分析确诊为良性前列腺增生和前列腺癌115例患者的临床资料,良性前列腺增生患者纳入良性组(80例),前列腺癌患者纳入恶性组(35例),所有患者均接受IVIM-DWI、DCE-MRI检查。比较2组患者IVIM-DWI[表观扩散系数(ADC)、真实扩散系数(D)、灌注分数(f)]、DCE-MRI[转运常数(K^(trans))、速率常数(K_(ep))、血管外细胞间隙体积百分数(V_(e))]定量参数差异,并使用受试者操作特征(ROC)曲线分析二者鉴别诊断效能,使用Pearson相关系数分析二者与Gleason评分的相关性。结果恶性组ADC、D、f、V_(e)低于良性组,K^(trans)、K_(ep)均高于良性组,差异有统计学意义(P<0.05);ADC、D、f、K^(trans)、K_(ep)、V_(e)对良性前列腺增生和前列腺癌鉴别诊断的曲线下面积(AUC)分别为0.951、0.831、0.725、0.708、0.849、0.787;恶性组不同Gleason评分患者ADC、D比较,差异有统计学意义(P<0.05),f、K^(trans)、K_(ep)、V_(e)比较,差异无统计学意义(P>0.05);ADC、D与Gleason评分负相关(P<0.05),f、V_(e)、K^(trans)、K_(ep)与Gleason评分无相关性(P>0.05)。结论IVIM-DWI与DCE-MRI均可有效鉴别良性前列腺增生和前列腺癌,其中IVIM-DWI的定量参数ADC、D可作为病情评估参考指标。

IVIM-DWI对可切除性胃腺癌脉管侵犯的预测价值

目的:探讨体素内不相干运动磁共振成像(IVIM-DWI)术前预测胃腺癌脉管侵犯的价值。方法:2021年1月-2022年5月,前瞻性搜集行根治性胃切除的胃腺癌患者的术前MRI资料,包括IVIM和DWI。根据术后病理结果,将患者分为有、无脉管侵犯组。测量胃癌病灶的厚度、ADC和IVIM-DWI参数(D、D^(*)、f)值,采用student t检验或Mann-Whitney U检验比较两组间连续变量的差异,采用逻辑回归分析筛选脉管侵犯的独立危险因素,采用ROC曲线评估各参数鉴别脉管侵犯状态的效能,采用Delong检验比较各参数预测效能的差异。结果:共纳入73例胃癌手术患者,其中49例有脉管侵犯(67.12%)。有脉管侵犯组的肿瘤处胃壁厚度大于无脉管侵犯组,而ADC、D和f值均低于无脉管侵犯组,差异均有统计学意义(P<0.05);两组间D^(*)值的差异无统计学意义(P>0.05)。ROC曲线分析显示肿瘤处胃壁厚度及ADC、D和f值均能有效预测脉管侵犯状态,AUC分别为0.821、0.686、0.792和0.727(P均<0.05)。肿瘤处胃壁厚度[OR:1.302(1.098~1.543)]和f[OR:686.801(6.126~77004.267)]是预测脉管侵犯的独立危险因素;联合两者进行诊断时,AUC、敏感度和特异度分别为0.897、81.63%和91.67%,其AUC显著高于ADC和f(Delong检验,P均<0.05),但与D和肿瘤处胃壁厚度的差异均无统计学意义(P=0.055、0.052)。结论:IVIM-DWI定量参数及肿瘤处胃壁厚度均能在术前有效预测胃癌脉管侵犯情况,尤其是肿瘤处胃壁厚度和f是胃癌患者脉管侵犯的独立危险因素,两者联合诊断可提高预测效能。

增强MRI联合IVIM-DWI诊断小肝细胞癌价值研究

目的探讨增强磁共振(MRI)联合体素内不相干运动磁共振扩散加权成像(IVIM-DWI)诊断小肝细胞癌(sHCC)的价值。方法2020年5月~2023年5月我院收治的肝脏局灶性病变患者73例,所有患者均接受增强MRI和IVIM-DWI检查,观察病灶增强强化信号特点,分析病灶IVIM-DWI定量参数,即伪扩散系数(D^(*))、真实扩散系数(D)和灌注分数(f)。采用细针穿刺或取术后组织行病理学检查。应用受试者特征工作曲线(ROC)下面积(AUC)评估增强MRI联合IVIM-DWI诊断sHCC的效能。结果经病理学检查,在73例肝脏局灶性病变患者中,诊断sHCC者49例(67.1%)和肝脏异型性增生结节(DN)者24例(32.9%);sHCC病灶T1WI低信号、T2WI高信号、动脉期强化和肝胆期低信号占比分别为61.2%、83.7%、59.2%和89.8%,均显著高于DN病灶的20.8%、33.3%、25.0%和29.2%(P<0.05);sHCC病灶D*和D分别为(50.9±11.6)×10^(-3) mm^(2)/s和(0.8±0.2)×10^(-3) mm^(2)/s,均显著小于DN病灶【分别为(78.4±15.8)×10^(-3) mm^(2)/s和(1.2±0.3)×10^(-3) mm^(2)/s,P<0.05】,而两组f比较,差异无统计学意义【分别为(45.6±8.7)%对(43.9±9.5)%,P>0.5】;ROC分析表明,应用T1WI信号、T2WI信号、动脉期强化、肝胆期信号、D*和D联合诊断sHCC的AUC为0.968,其灵敏度和特异度分别为100.0%和86.0%。结论应用增强MRI和IVIM-DWI联合诊断sHCC的效能较高,可为临床诊疗提供有益的依据,值得进一步深入研究。

腰椎间盘退行性变的T2加权像高信号区及椎间盘IVIM-DWI定量参数变化及临床意义

目的分析腰椎间盘退行性变患者T2加权像(T2WI)高信号区(HIZ)及椎间盘体素内不相干运动弥散加权成像(IVIM-DWI)定量参数变化,并探究其临床意义。方法选取2023年1月至2024年1月于我院进行腰椎MRI检查的72例患者,获得其L1/L2~L5/S1的椎间盘HIZ征象及IVIM-DWI定量参数,同时根据Pfirrmann分级标准将对应的椎间盘进行退行性变程度分级。对比不同Pfirrmann分级椎间盘的HIZ征象及IVIM-DWI定量参数,采用Spearman相关检验分析HIZ征象及IVIM-DWI定量参数与Pfirrmann分级的相关性。结果不同Pfirrmann分级椎间盘的有HIZ征象占比比较有统计学差异,体现为Ⅰ级<Ⅱ级<Ⅲ级<Ⅳ级(P<0.05),Ⅴ级与其余分级比较无统计学差异(P>0.05)。不同Pfirrmann分级椎间盘的前纤维环ADC、髓核ADC、后纤维环ADC、前纤维环D值、髓核D值、后纤维环D值、髓核f值、后纤维环f值比较有统计学差异(P<0.05),前纤维环D值、髓核D值、后纤维环D值、前纤维环f值比较无统计学差异(P>0.05)。Spearman相关检验分析显示,HIZ征象与Pfirrmann分级呈显著正相关(r=0.577,P<0.05);前纤维环ADC、髓核ADC、后纤维环ADC、前纤维环D值、髓核D值、后纤维环D值与Pfirrmann分级呈显著负相关(P<0.05),髓核f值、后纤维环f值与Pfirrmann分级呈显著正相关(P<0.05)。结论腰椎间盘退行性变患者T2WI HIZ征象及IVIM-DWI定量参数ADC、D值、f值与椎间盘Pfirrmann分级密切相关,有助于腰椎间盘退行性变的临床诊断。