Steffens J C, Link J, Brinkmann G, Reuter M, Heller M
Klinik für Radiologische Diagnostik, Christian-Albrechts-Universität zu Kiel.
Radiologe. 1997 Jul;37(7):566-71. doi: 10.1007/s001170050254.
During the last years, magnetic resonance angiography (MRA) has become a widely used modality for intracerebral and carotid artery imaging. Due to technical limitations, the clinical impact of MRA in the iliofemoral arteries has been rather poor. New developments in MRA like ECG-triggered sequences and the occurrence of contrast-enhanced MRA has overcome most of these limitations. Therefore, a major advance in clinical use of these diagnostic tools can be predicted. This paper discussed the advantages of ECG-gated 2D-Phase contrast, ECG-gated 2D-Time-of-Flight and contrast enhanced FLASH 3D angiography sequences from a clinical point of view. 2D-PC-MRA is a robust technique, which provides an overview of the iliofemoral artery system in less than 5 minutes. Limitations are the true 2D impression of the sequence and the partial venous overlay. 2D-TOF-MRA on the other hand is time consuming, however it enables 3D reconstruction and effective venous suppression can be applied. Contrast enhanced MRA as the third sequence discussed provides high resolution images in less than 30 sec. However contrast bolus timing might be a problem. In conclusion the authors suggest a combination of 2D-PC-MRA and additional 2D-TOF sequences at questionable vascular areas as the modality of choice, due to the fact, that MRA of the iliofemoral arteries ist mostly only one step of a complete lower limb examination. Contrast MRA might become the method of choice in the future however problems with multiple contrast injections and upper limits of contrast dose have to be solved.
在过去几年中,磁共振血管造影(MRA)已成为用于脑内和颈动脉成像的一种广泛应用的方式。由于技术限制,MRA在髂股动脉的临床应用效果一直相当差。MRA的新进展,如心电图触发序列和对比增强MRA的出现,已经克服了这些局限性中的大部分。因此,可以预测这些诊断工具在临床应用方面将取得重大进展。本文从临床角度讨论了心电图门控二维相位对比、心电图门控二维时间飞跃和对比增强快速扰相梯度回波三维血管造影序列的优势。二维相位对比MRA是一种可靠的技术,可在不到5分钟的时间内对髂股动脉系统进行概述。其局限性在于该序列的真正二维成像以及部分静脉重叠。另一方面,二维时间飞跃MRA耗时较长,不过它能够进行三维重建,并且可以应用有效的静脉抑制。作为讨论的第三种序列,对比增强MRA可在不到30秒的时间内提供高分辨率图像。然而,对比剂团注时间可能是个问题。总之,作者建议在血管情况存疑的区域将二维相位对比MRA与额外的二维时间飞跃序列相结合作为首选方式,因为髂股动脉的MRA大多只是完整下肢检查的其中一步。对比增强MRA未来可能会成为首选方法,不过必须解决多次注射对比剂的问题以及对比剂剂量上限问题。