保罗·霍奇斯(Paul C. Hodges),美国华盛顿大学医学博士,1919年受邀参加北京协和医学院放射科建科工作。在中国工作8年间,他为提高放射诊断水平、发展放射治疗学作出重要贡献。雷奇斯为北京协和医院放射科添置、改良X线摄影设备,建...保罗·霍奇斯(Paul C. Hodges),美国华盛顿大学医学博士,1919年受邀参加北京协和医学院放射科建科工作。在中国工作8年间,他为提高放射诊断水平、发展放射治疗学作出重要贡献。雷奇斯为北京协和医院放射科添置、改良X线摄影设备,建立X线检查规范化制度,成功设计了一套简单、便携且能适用于国内供电状况的X线机系统,并陆续安装于中国北部、中部、南部等地。此外,他开办了放射线学校并举办暑期训练班,培养了包括谢志光、荣独山、吴静、李果珍、汪绍训等多名中国放射学界专家,为中国放射学科的早期发展提供了坚实的人才与技术保障,堪称我国放射学专业的创始人。展开更多
Objective To explore the ability of texture analysis of gadoxetic acid-enhanced magnetic resonance imaging(MRI) T1 mapping images, as well as T1-weighted(T1 W), T2-weighted(T2 W) and apparent diffusion coefficient(ADC...Objective To explore the ability of texture analysis of gadoxetic acid-enhanced magnetic resonance imaging(MRI) T1 mapping images, as well as T1-weighted(T1 W), T2-weighted(T2 W) and apparent diffusion coefficient(ADC) maps for distinguishing between varying degrees of hepatic fibrosis in an experimental rat model.Methods Liver fibrosis in rats was induced by carbon tetrachloride intraperitoneal injection for 4–12 weeks(n = 30). In the control group(n = 10) normal saline was applied. The MRI protocol contained T2 W, diffusion weighted imaging, pre-and post-contrast image series of T1 W and T1 mapping images. METAVIR score was used to grade liver fibrosis as normal(F0), mild fibrosis(F1–2), and advanced fibrosis(F3–4). Texture parameters including mean gray-level intensity(Mean), standard deviation(SD), Entropy, mean of positive pixels(MPP), Skewness, and Kurtosis were obtained. Nonparametric Mann-Whitney U test was used to compare the average value of each texture parameter in each sequence for assessing the difference between F0 and F≥1 as well as F0–2 and F3–4. Receiver operating characteristic(ROC) curves were obtained to assess the diagnosing accuracy of the parameters for differentiating no liver fibrosis from liver fibrosis and rats with liver fibrosis grading F0–2 from those with grading F3–4. The area under ROC curve(AUC) was calculated to evaluate the diagnostic efficiency of texture parameters.Results Finally, 20 rats completed MR T1 mapping image scan. The pathologic staging of these 20 rats was no fibrosis(F0, n = 6), mild fibrosis(F1–2, n = 5) and advanced fibrosis(F3–4, n = 9). On pre-contrast T1 mapping image, Entropy was seen to be statistically significant higher in the F≥1 group than that in the F0 group at each spatial scaling factor(SSF) setting(P = 0.015, 0.015, 0.015, 0.013, 0.015 and 0.018 respectively to SSF = 0, 2, 3, 4,5, 6), and Mean of the F≥1 rats was statistically significant higher than that of the F0 rats at SSF 4, 5, 6(P = 0.004, 0.006, and 0.013, respectively). Entropy and Mean showed a moderate diagnostic performance in most SSF settings of T1 mapping pre-contrast images for differentiation of normal liver from liver fibrosis.Conclusion Certain texture features of gadoxetic acid-enhanced MR images, especially the Entropy of noncontrast T1 mapping image, was found to be a useful biomarker for the diagnosis of liver fibrosis.展开更多
文摘保罗·霍奇斯(Paul C. Hodges),美国华盛顿大学医学博士,1919年受邀参加北京协和医学院放射科建科工作。在中国工作8年间,他为提高放射诊断水平、发展放射治疗学作出重要贡献。雷奇斯为北京协和医院放射科添置、改良X线摄影设备,建立X线检查规范化制度,成功设计了一套简单、便携且能适用于国内供电状况的X线机系统,并陆续安装于中国北部、中部、南部等地。此外,他开办了放射线学校并举办暑期训练班,培养了包括谢志光、荣独山、吴静、李果珍、汪绍训等多名中国放射学界专家,为中国放射学科的早期发展提供了坚实的人才与技术保障,堪称我国放射学专业的创始人。
基金Supported by the National Science Foundation of China(Grant No.81501446)the National Public Welfare Basic Scientific Research Program of Chinese Academy of Medical Sciences(2018PT32003 and 2017PT32004)
文摘Objective To explore the ability of texture analysis of gadoxetic acid-enhanced magnetic resonance imaging(MRI) T1 mapping images, as well as T1-weighted(T1 W), T2-weighted(T2 W) and apparent diffusion coefficient(ADC) maps for distinguishing between varying degrees of hepatic fibrosis in an experimental rat model.Methods Liver fibrosis in rats was induced by carbon tetrachloride intraperitoneal injection for 4–12 weeks(n = 30). In the control group(n = 10) normal saline was applied. The MRI protocol contained T2 W, diffusion weighted imaging, pre-and post-contrast image series of T1 W and T1 mapping images. METAVIR score was used to grade liver fibrosis as normal(F0), mild fibrosis(F1–2), and advanced fibrosis(F3–4). Texture parameters including mean gray-level intensity(Mean), standard deviation(SD), Entropy, mean of positive pixels(MPP), Skewness, and Kurtosis were obtained. Nonparametric Mann-Whitney U test was used to compare the average value of each texture parameter in each sequence for assessing the difference between F0 and F≥1 as well as F0–2 and F3–4. Receiver operating characteristic(ROC) curves were obtained to assess the diagnosing accuracy of the parameters for differentiating no liver fibrosis from liver fibrosis and rats with liver fibrosis grading F0–2 from those with grading F3–4. The area under ROC curve(AUC) was calculated to evaluate the diagnostic efficiency of texture parameters.Results Finally, 20 rats completed MR T1 mapping image scan. The pathologic staging of these 20 rats was no fibrosis(F0, n = 6), mild fibrosis(F1–2, n = 5) and advanced fibrosis(F3–4, n = 9). On pre-contrast T1 mapping image, Entropy was seen to be statistically significant higher in the F≥1 group than that in the F0 group at each spatial scaling factor(SSF) setting(P = 0.015, 0.015, 0.015, 0.013, 0.015 and 0.018 respectively to SSF = 0, 2, 3, 4,5, 6), and Mean of the F≥1 rats was statistically significant higher than that of the F0 rats at SSF 4, 5, 6(P = 0.004, 0.006, and 0.013, respectively). Entropy and Mean showed a moderate diagnostic performance in most SSF settings of T1 mapping pre-contrast images for differentiation of normal liver from liver fibrosis.Conclusion Certain texture features of gadoxetic acid-enhanced MR images, especially the Entropy of noncontrast T1 mapping image, was found to be a useful biomarker for the diagnosis of liver fibrosis.
