New advances in magnetic resonance imaging (MRI) show enormous potential for a broad range ot new clinical and research applications including high-speed cardiovascular imaging, functional brain imaging, and contrast-sensitive image-guided intervention. They promise important advances in the assessment and treatment of cardiovascular disease, cancer and brain function. Central to their success are the dual demands of imaging speed and signal-to-noise ratio (SNR). Core biotechnology research that significantly advances MRJ speed and SNR are pivotal to progress and could impact new MRI applications across-the-board. This proposal, responsive to PAR-99-009 for Bioengineering Research, will directly advance MRI speed and SNR with innovative research in fourkey areas: the MRI gradient systems; high-speed multi-channel MRI receivers; new high-speed relaxation time (Ti) measurements and imaging; and the design of MRI detector coil systems that deliver the ultimate intrinsic SNR (UISNR)-the maximum that can be had. Specifically, we propose to develop compact, highly-efficient surface MRI gradient modules that can significantly increase gradient strength by more than an order of magnitude, and reduce gradient rise-times, and to develop algorithms to correct gradient nonlinearity. We will demonstrate the gradient advantages in a pilot study of diffusion MRI in acutestroke. We will develop a high-speed multi-channel receiver system with new analytic reconstruction methods for sensitivity-encoding to achieve manifold reductions in the minimum scan-time, and to realize the speed gains from the other projects, and we will demonstrate this with real-time MRT stress-testing of patients with ischemia. Ti relaxation is key to MRI contrast, and we propose new methods that promise dramatic reductions in Ti measurement times, Ti imaging, and we will demonstrate its potential for temperature monitoring during RF ablation therapy. andin human Ti studies. Finally, we introduced the USINR concept, and will now develop tools for designing coils that yield the UISNR, and build them for the head, heart, and abdomen, and will compare their performance to existingcoils. We hypothesize that the integration of radical redesigns of gradient, MRI detector coils, and high-speed contrast-sensitive MRI, will yield simultaneous performance gains that will provide truly new opportunities for clinical diagnostic and interventional research. The work will be implemented at 1 .5T and will directly and positively benefit 21 other funded research grants at this institution, with broad potential benefit to noninvasive imaging in a wide range of patients and diseases.

Agency
National Institute of Health (NIH)
Institute
National Center for Research Resources (NCRR)
Type
Research Project (R01)
Project #
1R01RR015396-01A1
Application #
6383206
Study Section
Diagnostic Imaging Study Section (DMG)
Program Officer
Levy, Abraham
Project Start
2001-09-30
Project End
2006-08-31
Budget Start
2001-09-30
Budget End
2002-08-31
Support Year
1
Fiscal Year
2001
Total Cost
$839,454
Indirect Cost
Name
Johns Hopkins University
Department
Radiation-Diagnostic/Oncology
Type
Schools of Medicine
DUNS #
045911138
City
Baltimore
State
MD
Country
United States
Zip Code
21218
Tasci, T Onur; Vargel, Ibrahim; Arat, Anil et al. (2009) Focused RF hyperthermia using magnetic fluids. Med Phys 36:1906-12
Feldman, Rebecca E; Hardy, Christopher J; Aksel, Bulent et al. (2009) Experimental determination of human peripheral nerve stimulation thresholds in a 3-axis planar gradient system. Magn Reson Med 62:763-70
Gabr, Refaat E; Schär, Michael; Edelstein, Arthur D et al. (2009) MRI dynamic range and its compatibility with signal transmission media. J Magn Reson 198:137-45
El-Sharkawy, AbdEl-Monem M; Qian, Di; Bottomley, Paul A (2008) The performance of interventional loopless MRI antennae at higher magnetic field strengths. Med Phys 35:1995-2006
Bottomley, Paul A (2008) Turning up the heat on MRI. J Am Coll Radiol 5:853-5
Kumar, Ananda; Bottomley, Paul A (2008) Optimized quadrature surface coil designs. MAGMA 21:41-52
Memis, Omer Gokalp; Eryaman, Yigitcan; Aytur, Orhan et al. (2008) Miniaturized fiber-optic transmission system for MRI signals. Magn Reson Med 59:165-73
Stralka, John P; Bottomley, Paul A (2007) A prototype RF dosimeter for independent measurement of the average specific absorption rate (SAR) during MRI. J Magn Reson Imaging 26:1296-302
Aksel, Bulent; Marinelli, Luca; Collick, Bruce D et al. (2007) Local planar gradients with order-of-magnitude strength and speed advantage. Magn Reson Med 58:134-43
Celik, Haydar; Uluturk, Asli; Tali, Turgut et al. (2007) A catheter tracking method using reverse polarization for MR-guided interventions. Magn Reson Med 58:1224-31

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