Objective To assess the clinical efficacy of neoadjuvant chemotherapy （NAC） for breast invasive ductal carcinoma with MR diffusion weighted imaging. Methods Thirty patients with breast invasive ductal carcinoma underwent conventional MRI scanning and diffusion weighted imaging examination before and after preoperative neoadj-uvant chemotherapy. Two experienced radiologists independently analyzed and measured the maximum lesion diameter and apparent diffusion coefficient （ADC） values before and after treatment，respectively. Statistical analysis was performed for testing the tumor maximum diameter and ADC values change by using the paired t-test. Results After NAC treatment，the maximum tumor diameter of invasive ductal breast carcinoma sharply reduced〔（4.33±0.83） cm vs. （2.04±0.64） cm，P＜0.001〕. When b value was 1 000，the mean ADC values of breast massess were significantly changed after NAC treatment〔（1.89±0.15） ×10-3mm2/s vs. （1.14±0.31） ×10-3mm2/s， P＜0.05〕. Conclusion MR diffusion weighted imaging can non-invasively and accurately assess the NAC efficacy， which are helpful for making surgical strategies.
目的 探讨磁共振扩散加权成像（DWI）、动脉自旋标记技术（ASL）、磁共振血管成像（MRA）联合应用在缺血性脑血管病诊断中的价值。 方法 对2010年3月－2012年5月经临床和影像学诊断的104例缺血性脑血管病患者，行常规MRI、液体衰减反转恢复序列、DWI及ASL、MRA序列检查，分析DWI、ASL、MRA多种技术显示病变的信号特征、面积大小及与血管关系。 结果 DWI对急性及亚急性脑梗死的检出率为100%，对大、小面积梗死病灶检出率无明显差异；ASL对大、小面积的急性及亚急性脑梗死的检出率有差异，对大面积梗死检出率为100%，对小面积梗死的检出率为70%；DWI和ASL对短暂性脑缺血发作的检出率分别为0%、70%，液体衰减反转恢复序列对短暂性脑缺血发作患者大脑皮层下斑状缺血灶检出最敏感。 结论 DWI和ASL均可用于急性脑梗死的早期诊断，ASL对大、小面积的急性及亚急性脑梗死的检出率有差异，DWI、ASL及MRA联合应用可准确评估缺血半暗区及侧支血管情况，在缺血性脑血管病诊断中有重要价值。
【摘要】 目的 探讨磁共振动态增强扫描及磁共振弥散加权成像（diffusion weighted imaging，DWI）对肝癌经导管动脉内化学栓塞（transcatheter arterial chemoembolization，TACE）治疗后的肿瘤残余及复发的判断价值。 方法 2009年1月-2010年10月，对28例经证实的肝癌患者在TACE治疗前、治疗后3~7 d及治疗后1~2个月、3~6个月行磁共振动态增强及DWI扫描，动态测量表观弥散系数（apparent diffusion coefficient，ADC）值，与数字减影血管造影（digital substraction angiography，DSA）检查对照，评价动态增强扫描及DWI对肿瘤残留或复发的检出能力。〖HTH〗结果 对肿瘤残余及复发的显示，动态增强扫描灵敏度为90.0%，特异度为96.9%；DWI灵敏度为96.7%，特异度为93.8%；动态增强扫描与DWI相结合的灵感度为100.0%，特异度为99.5%；DSA灵敏度和特异度分别为96.7%、100.0%。TACE治疗前所有肿瘤实质的ADC值为（1.134±0.014）×10-3 mm2/s；TACE治疗后3~7 d ADC值为（1.162±0.016）×10-3 mm2/s；TACE治疗后1~2个月碘油沉积较好，无明显残余或复发病灶的ADC值为（1.175±0.015）×10-3 mm2/s，3~6个月后随访病灶ADC值为（1.179±0.017）×10-3 mm2/s；TACE治疗后1~2个月碘油沉积不完全或无明显沉积病灶ADC值为（1.147±0.016）×10-3 mm2/s，3~6个月后随访病灶实质平均ADC值（1.142±0.012）×10-3 mm2/s。 结论 将动脉增强扫描与DWI相结合可提高对TACE治疗后肝癌残余及复发判断的灵敏度及特异度；对肿瘤组织平均 ADC值的动态测量、观察可及早判断肿瘤复发的可能性。【Abstract】 Objective To evaluate the dynamic contrast-enhanced MRI and diffusion weighted imaging (DWI) in judging the remnant and recurrence on hepatocellular carcinoma (HCC) after transcatheter arterial chemoembolization (TACE). Methods Between January 2009 and October 2010, 28 patients with HCC underwent dynamic contrast-enhanced MRI and DWI before and after TACE 3-7 days, 1-2 months and 3-6 months, respectively, and the apparent diffusion coefficient (ADC) value of the tumor were also measured at above mentioned time points. The sensitivity and specificity of dynamic contrast-enhanced MRI and DWI in diagnosis of residual tumor and recurrent cancer was qualitatively evaluated by comparing with the DSA results. Results Compared with DSA, the sensitivity and specificity of dynamic contrast-enhanced MRI were 90.0% and 96.9% by revealing the remnant and recurrence of HCC, while the sensitivity and specificity of DWI were 96.7% and 93.8% respectively. Combining dynamic contrast-enhanced MRI and DWI the sensitivity and specificity were improved to 100.0% and 99.5%, respectively. The mean ADC value of tumor before and after 3-7 days of TACE were (1.134±0.014)×10-3 and (1.162±0.016)×10-3 mm2/s, respectively. The mean ADC value of tumor without and with remnant and recurrence after 1-2 months and 3-6 months follow up were (1.175±0.015)×10-3, and (1.179±0.017)×10-3 mm2/s; (1.147±0.016)×10-3 and (1.142±0.012)×10-3 mm2/s, respectively. Conclusions Combining dynamic contrast-enhanced MRI and DWI could improve the sensitivity and specificity to detect the remnant and recurrence of HCC after TACE. Measuring the ADC value during follow up of HCC patients after TACE could predict the probability of tumor recurrence.
ObjectiveTo compare the effectiveness of T2 weighted image (T2WI) and some compounded MRI techniques, including T2WI combined with magnetic resonance spectroscopy (T2WI+MRS), T2WI combined with diffusion weighted imaging (T2WI+DWI) and T2WI combined with dynamic contrast-enhancement [T2WI+(DCE-MRI)] respectively, with 1.5 T MR scanner in diagnosing prostate cancer through a blinding method. MethodsBetween March 2011 and April 2013, two observers diagnosed 59 cases with a blinding method. The research direction of radiologist A was to diagnose prostate cancer. The observers diagnosed and scored the cases with T2WI, T2WI+(DCE-MRI), T2WI+MRS, T2WI+DWI and compositive method respectively. The data were statistically analyzed with receiver operating characteristic (ROC) curve. ResultsAccording to the ROC curve, both observers got the sequence of area under curve (AUC) as T2WI+DWI > T2WI+(DCE-MRI) > T2WI+MRS > T2WI. On the basis of the result from observer A, the AUC from each technique was similar. The AUC of T2+DWI was slightly bigger than others. The specificity of single T2WI was the lowest; the sensitivity of T2WI was slightly higher. The AUC of the compositive method was marginally larger than T2WI+DWI. According to the result from observer B, the AUC of T2WI+DWI was obviously larger than the others. The AUC of single T2WI was much smaller than the other techniques. The single T2WI method had the lowest sensitivity and the highest specificity. The AUC of T2WI+DWI was slightly larger than the compositive method. The AUC of T2WI+(DCE-MRI), T2WI+MRS, single T2WI methods from observer A was obviously higher than those from the score of observer B. The AUC of T2WI+DWI from the two observers was similar. ConclusionThe method of combined T2WI and functional imaging sequences can improve the diagnosing specificity when a 1.5 T MR scanner is used. T2WI+DWI is the best method in diagnosing prostate cancer with least influence from the experience of observers in this research. The compositive method can improve the diagnosis of prostate cancer effectively, but when there are contradictions between different methods, the T2WI+DWI should be considered as a key factor.
This paper aims to investigate the value of diffusiion weighted imaging (DWI) and different apparent diffusion coefficient (ADC) methods to predict the curative effects of neoadjuvant chempotherapy (NAC) for breast cancer. From March 2010 to December 2012, seventy-one patients were pathologically confirmed invasive breast cancer by needle puncture biopsy received before surgery, and underwent magnetic resonance before and after NAC, the ADC were measured by mean ADC method and lower ADC method. The pathologic response after NAC was divided to major histological response (MHR) group and non-major histological response (NMHR) group according to Miller & Payne system. Results displayed that ADC values obtained before NAC, at the end of the second cycle of NAC, and after whole course of treatment, had good correlations between mean and lower ADC methods (the Pearson's correlation=0.699, 0.749 and 0.895, respectively). Significant difference in ADC obtained both with mean and lower ADC methods could be found between MHR and NMHR groups after the second cycle of NAC (P<0.05). After the second cycle of NAC, significant difference in the change rate of ADC could be found between MHR and NMHR groups by using lower ADC method (P<0.05), but not be found by using mean ADC method (P＞0.05). In conclusion, DWI could monitor the pathologic changes of breast cancer after NAC, and the lower ADC method might be used to evaluate the curative effect of NAC with the change rate of ADC.
ObjectiveTo discuss application and research progress of intravoxel incoherent motion diffusion weighted imaging (IVIM-DWI) in liver and pancreas. MethodThe literatures about application and research progress of IVIM-DWI in liver and pancreas were researched and reviewed. ResultsWith the development of MRI, IVIM-DWI has become the hot research spot, and also has been widely used in liver and pancreas. It could make up the disadvantage of traditional DWI. IVIM-DWI holds an obvious value to assess the level of hepatic fibrosis or cirrhosis and differential diagnosis of liver tumors, diagnosis of pancreatic cancer and differential diagnosis of pancreatic cancers and mass type chronic pancreatitis. ConclusionIVIM-DWI has a great value in research of liver and pancreas, it is worth to be studied further.
ObjectiveTo summarize the application of magnetic resonance imaging (MRI) in the evaluation of pancreatic exocrine function.MethodIn this paper, we reviewed and summarized the related literatures about the application of MRI in the field of pancreatic exocrine function evaluation in recent years.ResultsA variety of MRI techniques could be used to detect the pancreatic exocrine function. In addition to conventional MRI techniques, there were also MRI stimulated by pancreatic secretions, cine (dynamic) cholangiopancreatography based on space selective reverse recovery pulse, and so on.ConclusionThe new MRI techniques have potential for semi-quantitative and quantitative evaluation of pancreatic exocrine function.
ObjectivesTo investigate the diagnostic value of different diffusion-weighted MRI (DWI) models between two Gaussian DWI models including mono-exponential and bi-exponential, and the non-Gaussian kurtosis model in poorly differentiated pancreatic ductal adenocarcinoma.MethodsSubjects comprised 52 patients with poorly differentiated pancreatic ductal adenocarcinoma which had been confirmed by surgery. All patients underwent DWI (1.5T, multi-b values: 0, 50, 100, 150, 200, 500, 800, 1000, 1 500, 2 000s/mm2). Mean values of DWI-derived metrics ADCstandard, ADCslow, ADCfast, f, MD, MK and ADCstandard were calculated from regions of interest in all tumours and non-tumorous parenchyma and compared. ANOVA and Mann Whitney U test was used to compare the MRI paremeters. ROC was used to evaluate the diagnostic efficiency.ResultsMean ADCstandard, ADCfast, f and MK values showed significant differences between tumours and non-tumorous parenchyma (P<0.05). AUC for ADCstandard, MD, ADCfast and f were 0.705, 0.665, 0.648, 0.614, respectively. The ROC curve integrated with ADCstandard and MD had better diagnostic efficiency (AUC was about 0.754).ConclusionsADCstandard, ADCfast, f and MK values can differentiate tumours from non-tumorous parenchyma. The combination of Gaussion distribution model and non-Gaussion distribution model has the potential to increase the diagnostic accuracy of DWI in patients with pancreatic ductal adenocarcinoma.
ObjectiveTo investigate the utility of stretched exponential model diffusion-weighted imaging (DWI) for diagnosing of advanced liver fibrosis.MethodsThe patients with chronic liver disease complicated with vary degrees of fibrosis confirmed by pathological examination underwent DWI using different b-values (0, 50, 600 s/mm2) at the First Affiliated Hospital of Chengdu Medical College from June 2015 to February 2020 were collected. In addition, patients who underwent upper abdominal MRI examination in the same hospital at the same time and had no liver disease or disease affecting liver function were collected as a control group. The apparent diffusion coefficient (ADC) was calculated by using a mono-exponential model. The distributed diffusion coefficient (DDC) and water molecular diffusion heterogeneity index (α) were calculated by using a stretched exponential model. The fibrosis stage was evaluated by using the Metavir scoring system. The ADC, DDC, and α among different fibrosis groups were compared. The receiver operating characteristic (ROC) curve was used to analyze the diagnostic efficacy of these three quantitative parameters for advanced liver fibrosis.ResultsA total of 42 patients with chronic liver disease were collected in this study, including mild liver fibrosis (S1–S2, n=16) and advanced liver fibrosi (≥S3, n=24); 15 patients in the control group. The values of ADC, DDC, and α of the patients with mild liver fibrosis and advanced liver fibrosis were significantly lower than those of the control patients (P<0.05). The area under the ROC curve of ADC, DCC, and α in diagnosing liver fibrosis (≥S1) was 0.915, 0.974, and 0.835, respectively, which in diagnosing advanced liver fibrosis (≥S3) was 0.744, 0.869, and 0.758, respectively. However, further the area under ROC curve among these three metrics had no statistical differences (P>0.05).ConclusionDDC based on stretched exponential model is valuable for diagnosis of advanced liver fibrosis.