The goal of this proposal is to develop Magnetic Resonance (MR) pulse sequences capable of accurate assessment of the renal vasculature in the routine clinical environment. A successful conclusion could potentially replace the current, invasive x-ray arteriography techniques. Furthermore, MR imaging would then be in a position to provide a comprehensive renal exam by using these results to complement existing MR techniques which are capable of measuring mass and flow and imaging renal parenchyma. The difficulty with imaging renal blood flow is primarily related to artifacts resulting from respiratory, cardiac, and peristaltic motion. Additionally, the tortuosity of the vasculature forms complex flow patterns which can lead to spin dephasing and signal loss. These problems are to be addressed through three complementary areas: sequences based upon multi-dimensional RF pulses and spiral readout gradients, respiratory immunity techniques, and fast gradient hardware. Combinations of these techniques will be explored with the goals of eliminating motion artifacts, improving vessel conspicuity, and reducing scan time. The developed sequences will be assessed in tests with phantoms, normal volunteers and patients. Image quality will be evaluated against results from current state-of-the-art MR techniques and x-ray arteriography in order to identify the most promising methods.
Di Bisceglie, Adrian M; Hoofnagle, Jay H (2002) Optimal therapy of hepatitis C. Hepatology 36:S121-7 |
Alley, M T; Napel, S; Amano, Y et al. (1999) Fast 3D cardiac cine MR imaging. J Magn Reson Imaging 9:751-5 |
Alley, M T; Glover, G H; Pelc, N J (1998) Gradient characterization using a Fourier-transform technique. Magn Reson Med 39:581-7 |
Alley, M T; Shifrin, R Y; Pelc, N J et al. (1998) Ultrafast contrast-enhanced three-dimensional MR angiography: state of the art. Radiographics 18:273-85 |
Alley, M T; Pauly, J M; Sommer, F G et al. (1997) Angiographic imaging with 2D RF pulses. Magn Reson Med 37:260-7 |