多层块薄层重迭采集与移行预饱和法在颈部动脉MRA中的应用

目的：探讨多层块薄层重迭采集（ ＭＯＴＳＡ） 与移行预饱和组合序列（ＴＳＣ） 在颈部动脉ＭＲＡ 中的应用，以选择颈部ＭＲＡ 的优化序列组合。材料和方法：正常人组４０ 例，疾病组４ 例。均同时行ＭＯＴＳＡ、ＴＳＣＭＲＡ。结果：ＭＯＴＳＡ 技术空间分辨力高，血管／ 背景对比好，病变显示清晰，但检查时间长，层块间可见饱和伪影；ＴＳＣ ＭＲＡ 血流信号强度高，块间连接简便，无饱和伪影，缺点是对涡流敏感，空间分辨力较低。结论：以２Ｄ ＴＳＣ 观察血管全长，３Ｄ ＴＯＦ－ ＴＯＮＥ 观察血管局部是颈部动脉ＴＯＦ 法ＭＲＡ 较好的序列组合。

Prospective Evaluation of Extracranial Cerebral Artery: Correlation between MR Angiography with MOTSA and MR Angiography with TSC

Purpose: To compare multiple overlapping thin slab acquisition (MOTSA) with travelling sat combine (TSC) in MR angiography of the extracranial cerebral artery. Materials and Methods: The extracranial arteries in forty volunteers and four cases with occlusive disease of cerebral artery were studied with MOTSA MRA and TSC MRA prospectively. Results: MOTSA was better resolution than TSC technique. MOTSA provided better delineation of vassel margin of the artery but scan times were longer and differences in saturation between different slabs led to saturation artifact. TSC provided maximal flow related enhancemet and gave the enire course of extracranial cerebral artery easier than MOTSA, problems with TSC included decreased spatical resolution, increased sensitivity to turbulence (in-plane saturation). Conclusion: 2D TOF TSC is an ideal technique for the entire course of the extracranial artery. 3D TOF TONE is of benefit to defined region of interest.