报告题目: |
Noncontrast MR Angiography Using Flow-Sensitive Dephasing Magnetization Prepared SSFP |
报告人: |
Zhaoyang Fan |
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Ph.D.
Cedars-Sinai Medical Center,
Los Angeles, CA, USA
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报告时间: |
2010-10-15 15:00 |
报告地点: |
医学科学楼C201 |
主办单位: |
清华生物医学影像研究中心中心/医学院生物医学工程系 |
简介: |
Peripheral artery disease (PAD) is a major cause of diminished functional capacity and quality of life in a large portion of western populations. The current “gold standard” for diagnosing PAD, x-ray angiography, is an invasive, costly procedure and requires ionizing radiation and nephrotoxic contrast media. While contrast-enhanced MR angiography is being accepted as a routine non-invasive diagnostic tool, safety concerns of gadolinium contrast medium in patients with severe renal insufficiency have recently triggered renewed interests in noncontrast MRA (NC-MRA).
The aim of this work was to develop 3D NC-MRA technique for peripheral arteries. By exploiting arterial flow pulsatility, a flow-sensitive dephasing (FSD) magnetization preparation was implemented to exclusively suppress artery blood flow signal during a balanced steady-state free precession acquisition. Magnitude subtraction of a dark-artery measurement acquired with an FSD-preparation during systole and a bright-artery measurement acquired with a T2-preparation during diastole results in an artery-only 3D data set. MRA of peripheral arteries with large spatial coverage, isotropic, high spatial resolution, excellent background suppression, and minimal venous signal contamination was achieved with the technique. Moreover, the optimization of the blood-suppressing capability of the FSD module was performed to address several technical issues, including stripe image artifacts, determination of the required flow sensitivity, signal suppression of a multi-directional flow. Preliminary results on healthy volunteers and a limited number of patients have indicated the promise of the technique in MRA of the lower extremities and hands. Systematic clinical studies are warranted to further validate its diagnostic value. |
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