扫描持续时间对动态对比度增强磁共振成像脑病变的药物动力学参数的影响
Silvia Minosse1, Eliseo Picchi2, Valentina Ferrazzoli3
1Diagnostic Imaging Unit, Department of Biomedicine and Prevention, University of Rome Tor Vergata, Viale Oxford 81, Rome 00133, Italy.
Magnetic resonance imaging
|November 8, 2023
概括
动态对比增强MRI (DCE-MRI) 药动力学参数,特别是Kep和Ve,在脑瘤中是时间依赖的. 为了可靠的测量,需要更长的扫描时间,而Ktrans在采集持续时间中保持一致.
科学领域:
- 放射学 放射学是一门学科.
- 在瘤学瘤学.
- 医疗成像医学成像
背景情况:
- 基于加多的对比剂需要时间才能在体内分布,以获得准确的成像.
- 在DCE-MRI中,采集时间短 (<10分钟) 可能导致不可靠的药理动力学参数估计.
- 关于延长扫描时间对脑瘤成像中的DCE-MRI参数的影响的研究有限.
研究的目的:
- 研究DCE-MRI衍生的动力参数 (Ktrans,Ve,Kep) 如何随着不同的采集时间 (5-10分钟) 变化.
- 为了确定最佳的扫描持续时间可靠的DCE-MRI参数评估在脑瘤.
- 为了确定哪些DCE-MRI参数受到脑瘤患者扫描持续时间的影响最大.
主要方法:
- 在3T时获得的52名脑瘤患者的DCE-MRI数据的回顾性分析.
- 从5到10分钟的扫描时间生成定量DCE-MRI图 (Ktrans,Ve,Kep)
- 使用Kruskal-Wallis测试和变化系数 (CoV) 进行统计比较,以评估不同扫描长度的参数变化.
主要成果:
- 在对比增强 (CE) 卷内,Ktrans参数在扫描持续时间之间没有显著差异.
- 在CE卷中的Ve和Kep参数受到数据长度的显著影响,特别是在5到10分钟之间.
- 对Kep的变化系数从0.70 (高度可变) 在5分钟下降到0.42 (轻微可变) 在10分钟.
结论:
- 脑瘤中的Kep和Ve是时间依赖的参数,需要更长的扫描时间来准确量化.
- Ktrans 是一个时间独立的参数,即使采集时间较短,它也是一种可靠的测量方法.
- 延长DCE-MRI扫描持续时间对于在脑瘤评估中获得可靠的动力参数值至关重要.
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