肺血管磁共振成像:比较二维TOF、三维TOF及Gd-DTPA增强

PULMONARY MR ANGIOGRAPHY:A COMPARISON OF 2D-TOF,3D-TOF AND Gd-DTPA ENHANCEMENT

目的：探讨２种常用的ＭＲ血管成像方法对正常肺动脉图像质量的影响及Ｇｄ－ＤＴＰＡ在其中的作用。材料和方法：用１．０Ｔｅｓｌａ超导ＭＲＩ系统，体线圈技术，随机选择无心肺疾患志愿者４６例，行２ＤｔｕｒｂｏＦＬＡＳＨ和／或３ＤＦＩＳＰ肺部ＭＲＡ检查共１１３次，行Ｇｄ－ＤＴＰＡ增强后２ＤｔｕｒｂｏＦＬＡＳＨ和／或３ＤＦＩＳＰ扫描共４７次。计算机测量肺动脉和背景噪声的信号强度，计算出肺动脉的信噪比（ＳＮＲ），并对肺动脉分支数量进行计数定量分析。结果：３Ｄ－ＴＯＦＭＲ血管成像的图像质量优于２Ｄ－ＴＯＦ，Ｇｄ－ＤＴＰＡ增强后可明显改善２Ｄ和３Ｄ－ＴＯＦＭＲＡ的图像质量，Ｇｄ－ＤＴＰＡ增强后３Ｄ比２Ｄ－ＴＯＲＦＭＲＡ的肺外周动脉分支数量有明显差异（Ｐ＜０．０１）。结论：３Ｄ－ＴＯＦＭＲ血管成像对肺动脉的显示较好，Ｇｄ－ＤＴＰＡ增强后可显著提高肺动脉的ＳＮＲ和肺段支以下的动脉分支数，改善图像质量。

Objective:To evaluate the image quality of the normal pulmonary arteries with 2D and 3D time-of-flight (TOF) methods and the effect of Gd-DTPA. Materials and Methods:Imaging was performed using a 1.0 Tesla superconducting MR system with a body coil.Two-dimensional (2D) turbo FLASH sequence and/or three-dimensional (3D) FISP sequence were performed in 46 persons with the total of 113 times pulmonary MRA.(47 pulmonary MRA were gained after Gd-DTPA were injected).Image quality were quantified by measuring signal-to-noise ratio (SNR) of pulmonary arteries and counting the numbers of pulmonary arteries. Results: The image quality of pulmonary 3D-TOF MRA was superior to that of pulmonary 2D-TOF MRA.After Gd-DTPA was injected,the image of pulmonary 2D and 3D-TOF MRA were improved and pulmonary arterial visualization of 3D-TOF MRA was better than 2D-TOF MRA ( P <0.01). Conclusions:Pulmonary three-dimensional TOF MR angiography is better in demonstrating pulmonary arteries.The SNR and the numbers of pulmonary arteries were improved significantly after intravenous gadolinium.