Medical Physics in Radiology, German Cancer Research Center, Heidelberg, Germany.
Magn Reson Med. 2010 Feb;63(2):517-23. doi: 10.1002/mrm.22228.
The present study proposes a catheter system with an expandable coil etched on a polyimide foil. The catheter system combines the advantages of a small insertion diameter when the coil is rolled up in a protective carrier sheath with an increased signal-to-noise ratio (SNR) and penetration depth when the coil is pushed out. After imaging, the coil can be retracted into the sheath and folded back into the initial rolled-up configuration due to the tapered geometry of the carrier foil. The catheter system was tested on two healthy anesthetized pigs, including tracking and high-resolution intravascular imaging. To reduce artifacts in high-resolution images induced by catheter motion in the pulsatile blood flow, a motion-gating method was implemented that combines a flow-compensated two-dimensional fast low angle shot (FLASH) imaging sequence with the acquisition of projection data for retrospective gating. Using the projection data for motion detection, image SNR was increased by up to 500% over uncorrected images, and anatomic structures of 150 microm size could be differentiated in the aorta.
本研究提出了一种带有可扩张线圈的导管系统，该线圈蚀刻在聚酰亚胺薄膜上。该导管系统结合了线圈在保护性输送鞘中卷起时插入直径小的优点，以及线圈推出时信噪比（SNR）和穿透深度增加的优点。成像后，由于输送箔的锥形几何形状，线圈可以缩回护套中并折叠回初始卷起的配置。该导管系统在两只健康麻醉的猪身上进行了测试，包括跟踪和高分辨率血管内成像。为了减少由于脉动血流中导管运动引起的高分辨率图像中的伪影，实现了一种运动门控方法，该方法将流动补偿二维快速小角度激发（FLASH）成像序列与用于回顾性门控的投影数据采集相结合。使用投影数据进行运动检测，图像 SNR 比未校正图像增加了高达 500%，并且可以在主动脉中分辨出 150 微米大小的解剖结构。
