近年来,19F磁共振(19F magnetic resonance,19F-MR)分子成像在靶向药物递送领域展现了广阔的应用前景。鉴于19F原子较高的灵敏度以及体内缺乏内源性氟背景信号,以包括液态全氟化碳(perfluorocarbons,PFC)在内的许多纳米材料被研发和应...近年来,19F磁共振(19F magnetic resonance,19F-MR)分子成像在靶向药物递送领域展现了广阔的应用前景。鉴于19F原子较高的灵敏度以及体内缺乏内源性氟背景信号,以包括液态全氟化碳(perfluorocarbons,PFC)在内的许多纳米材料被研发和应用成为19F-MR成像的理想分子成像探针。19F-MR将分子成像技术与药物递送系统有机结合,从而实现对疾病的早期分子水平诊断、靶向治疗、疗效的实时监测与预后的精准判断。笔者对多种可用于19F-MR分子成像的纳米分子成像探针在靶向药物递送和智能化药物控释体系中的应用研究进展进行综述,讨论它们在该领域开展应用情况以及各自优缺点,以期为新型可用于19F-MR分子成像的多功能纳米材料的设计、制备、研发及应用提供理论依据和数据支撑。展开更多
尽管心血管磁共振(cardiovascular magnetic resonance,CMR)成像已有几十年坚实的实践基础,但既往较长的扫描时间导致其临床应用受限,亟需标准化快速成像方案以解决临床问题。笔者根据心血管磁共振协会发布的白皮书并结合最新研究进展,...尽管心血管磁共振(cardiovascular magnetic resonance,CMR)成像已有几十年坚实的实践基础,但既往较长的扫描时间导致其临床应用受限,亟需标准化快速成像方案以解决临床问题。笔者根据心血管磁共振协会发布的白皮书并结合最新研究进展,对30 min或更短时间CMR检查的常见临床指征、基础设施、流程方法及拓展技术进行解读,以期促进全球范围的应用与推广。展开更多
随着心肌梗死(myocardial infarction,MI)相关研究证据的更新,许多基于心血管磁共振(cardiovascular magnetic resonance,CMR)形态学、功能学及组织学的参数与MI硬终点事件密切相关,这使得CMR参数可以成为MI研究中有效的终点事件替代性...随着心肌梗死(myocardial infarction,MI)相关研究证据的更新,许多基于心血管磁共振(cardiovascular magnetic resonance,CMR)形态学、功能学及组织学的参数与MI硬终点事件密切相关,这使得CMR参数可以成为MI研究中有效的终点事件替代性指标,即CMR终点。2019年美国心脏病学院基金会(American College of Cardiology Foundation,ACCF)发布了MI相关基础实验及临床试验的CMR终点选择专家共识,该共识基于大量研究证据及前沿的研究成果,总结了心肌缺血/再灌注损伤的病理生理改变以及MI的CMR组织学特征,同时对MI相关研究的CMR终点选择进行推荐。笔者就该共识对既往观点的更新和补充进行解读,旨在为未来MI与CMR相关领域的基础及临床研究方向提供参考依据。展开更多
Objectives: This study sought to investigate the influence of time, dose, and inversion time(TI) and their interactions on myocardial infarct size measurements to establish the foundation for a standardized protocol f...Objectives: This study sought to investigate the influence of time, dose, and inversion time(TI) and their interactions on myocardial infarct size measurements to establish the foundation for a standardized protocol for multicenter trials. Background: There is growing interest in using magnetic resonance imaging(MRI) infarct size measurements as an end point in clinical trials. However, no standardized protocol exists, and there are limited data concerning the effects of time, contrast agent dose, and TI. Methods: First, we determined the influence of postcontrast imaging time(5 to 40 min), contrast agent dose(0.1 vs. 0.2 mmol/kg), TI, and their interactions in an animal model(n=14). Second, we tested whether the findings of the animal study apply to patients and are generalizable. Therefore, we retested the diagnostic window in a multicenter study. A total of 48 patients with first acute myocardial infarction(AMI) from three centers were imaged twice(5 and 30 min) after injection of 0.15 mmol/kg gadolinium diethylenetriamine-pentaacetate using an adjusted TI. Results: The animal study showed that the infarct size is independent of time and dose(p=0.9 and p=0.16, respectively) using an adjusted TI. Using a fixed TI, however, infarct size is a function of time and dose(p=0.0001 and p=0.01, respectively). The multicenter study showed that MRI 1(16.9±12%of left ventricle) was not statistically different from MRI 2(16.4±12%of left ventricle, p=NS)with no difference between sites(p=NS). Conclusions: The AMI size can be measured with MRI using a contrast dose between 0.1 and 0.2 mmol/kg and a time window of 5 to 30 min after contrast administration, provided that the TI is adjusted.展开更多
目的 利用MRI影像数据,基于亚型与阶段推断算法(SuStaIn)构建精神分裂症(SCZ)与双相情感障碍(BD)跨诊断的脑萎缩进展亚型框架。方法 纳入190例SCZ与BD患者,以及158名健康对照组。基于其T1WI MRI影像,提取17个感兴趣脑区的灰质体积(GMV)...目的 利用MRI影像数据,基于亚型与阶段推断算法(SuStaIn)构建精神分裂症(SCZ)与双相情感障碍(BD)跨诊断的脑萎缩进展亚型框架。方法 纳入190例SCZ与BD患者,以及158名健康对照组。基于其T1WI MRI影像,提取17个感兴趣脑区的灰质体积(GMV),利用SuStaIn进行亚型与分期建模。利用方差分析评估亚型间临床特征差异,Spearman分析验证临床特征差异及其与模型分期的相关性。结果 SuStaIn模型识别出两类不同的大脑萎缩进展轨迹:小脑主导型(以小脑起始,逐步累及布洛卡区、额叶与岛叶)与前额叶主导型(以额叶起始,扩展至扣带回、颞叶)。前额叶主导型患者在阳性症状评分上显著高于小脑主导型(14.2±5.4 vs. 9.15±4.1,P=0.029)。亚组分析表明:前额叶主导型患者表现出更严重的阳性症状(BD:14.4±5.2 vs. 11.3±4.5,P=0.041;SCZ:8.6±2.8 vs. 7.2±1.7,P=0.038)。两种亚型的小脑(r=-0.169,P=0.007)和前额叶(r=-0.193,P=0.002)GMV随分期推移均呈下降趋势,阳性症状(r=0.331,P=0.012)、阴性症状(r=0.283,P=0.033)及一般症状(r=0.411,P=0.002)的症状严重程度增加。结论基于横断面MRI数据,发现SCZ与BD的两类跨诊断脑萎缩路径,且随分期推移,临床症状加重。结果支持精神障碍为一种具有明确空间-时间进展特征的神经退行性过程。展开更多
文摘近年来,19F磁共振(19F magnetic resonance,19F-MR)分子成像在靶向药物递送领域展现了广阔的应用前景。鉴于19F原子较高的灵敏度以及体内缺乏内源性氟背景信号,以包括液态全氟化碳(perfluorocarbons,PFC)在内的许多纳米材料被研发和应用成为19F-MR成像的理想分子成像探针。19F-MR将分子成像技术与药物递送系统有机结合,从而实现对疾病的早期分子水平诊断、靶向治疗、疗效的实时监测与预后的精准判断。笔者对多种可用于19F-MR分子成像的纳米分子成像探针在靶向药物递送和智能化药物控释体系中的应用研究进展进行综述,讨论它们在该领域开展应用情况以及各自优缺点,以期为新型可用于19F-MR分子成像的多功能纳米材料的设计、制备、研发及应用提供理论依据和数据支撑。
文摘尽管心血管磁共振(cardiovascular magnetic resonance,CMR)成像已有几十年坚实的实践基础,但既往较长的扫描时间导致其临床应用受限,亟需标准化快速成像方案以解决临床问题。笔者根据心血管磁共振协会发布的白皮书并结合最新研究进展,对30 min或更短时间CMR检查的常见临床指征、基础设施、流程方法及拓展技术进行解读,以期促进全球范围的应用与推广。
文摘随着心肌梗死(myocardial infarction,MI)相关研究证据的更新,许多基于心血管磁共振(cardiovascular magnetic resonance,CMR)形态学、功能学及组织学的参数与MI硬终点事件密切相关,这使得CMR参数可以成为MI研究中有效的终点事件替代性指标,即CMR终点。2019年美国心脏病学院基金会(American College of Cardiology Foundation,ACCF)发布了MI相关基础实验及临床试验的CMR终点选择专家共识,该共识基于大量研究证据及前沿的研究成果,总结了心肌缺血/再灌注损伤的病理生理改变以及MI的CMR组织学特征,同时对MI相关研究的CMR终点选择进行推荐。笔者就该共识对既往观点的更新和补充进行解读,旨在为未来MI与CMR相关领域的基础及临床研究方向提供参考依据。
文摘Objectives: This study sought to investigate the influence of time, dose, and inversion time(TI) and their interactions on myocardial infarct size measurements to establish the foundation for a standardized protocol for multicenter trials. Background: There is growing interest in using magnetic resonance imaging(MRI) infarct size measurements as an end point in clinical trials. However, no standardized protocol exists, and there are limited data concerning the effects of time, contrast agent dose, and TI. Methods: First, we determined the influence of postcontrast imaging time(5 to 40 min), contrast agent dose(0.1 vs. 0.2 mmol/kg), TI, and their interactions in an animal model(n=14). Second, we tested whether the findings of the animal study apply to patients and are generalizable. Therefore, we retested the diagnostic window in a multicenter study. A total of 48 patients with first acute myocardial infarction(AMI) from three centers were imaged twice(5 and 30 min) after injection of 0.15 mmol/kg gadolinium diethylenetriamine-pentaacetate using an adjusted TI. Results: The animal study showed that the infarct size is independent of time and dose(p=0.9 and p=0.16, respectively) using an adjusted TI. Using a fixed TI, however, infarct size is a function of time and dose(p=0.0001 and p=0.01, respectively). The multicenter study showed that MRI 1(16.9±12%of left ventricle) was not statistically different from MRI 2(16.4±12%of left ventricle, p=NS)with no difference between sites(p=NS). Conclusions: The AMI size can be measured with MRI using a contrast dose between 0.1 and 0.2 mmol/kg and a time window of 5 to 30 min after contrast administration, provided that the TI is adjusted.
文摘目的 利用MRI影像数据,基于亚型与阶段推断算法(SuStaIn)构建精神分裂症(SCZ)与双相情感障碍(BD)跨诊断的脑萎缩进展亚型框架。方法 纳入190例SCZ与BD患者,以及158名健康对照组。基于其T1WI MRI影像,提取17个感兴趣脑区的灰质体积(GMV),利用SuStaIn进行亚型与分期建模。利用方差分析评估亚型间临床特征差异,Spearman分析验证临床特征差异及其与模型分期的相关性。结果 SuStaIn模型识别出两类不同的大脑萎缩进展轨迹:小脑主导型(以小脑起始,逐步累及布洛卡区、额叶与岛叶)与前额叶主导型(以额叶起始,扩展至扣带回、颞叶)。前额叶主导型患者在阳性症状评分上显著高于小脑主导型(14.2±5.4 vs. 9.15±4.1,P=0.029)。亚组分析表明:前额叶主导型患者表现出更严重的阳性症状(BD:14.4±5.2 vs. 11.3±4.5,P=0.041;SCZ:8.6±2.8 vs. 7.2±1.7,P=0.038)。两种亚型的小脑(r=-0.169,P=0.007)和前额叶(r=-0.193,P=0.002)GMV随分期推移均呈下降趋势,阳性症状(r=0.331,P=0.012)、阴性症状(r=0.283,P=0.033)及一般症状(r=0.411,P=0.002)的症状严重程度增加。结论基于横断面MRI数据,发现SCZ与BD的两类跨诊断脑萎缩路径,且随分期推移,临床症状加重。结果支持精神障碍为一种具有明确空间-时间进展特征的神经退行性过程。
