Paul A. Bottomley, Ph.D.
Director, Division of MR Research
The focus of our work is the development and evaluation of magnetic resonance (MR) techniques that will hopefully lead to an every-day clinical application of the modality to the heart, especially to ischemic heart disease.
• Phosphorus MR studies of myocardial energy metabolism
We have used spatially localized phosphorus MR spectroscopy (MRS) to measure noninvasively high-energy phosphate metabolites such as ATP (adenosine triphosphate) and phosphocreatine (PCr) in the heart. These metabolites are responsible for muscular contraction: their ratio can change during stress-induced ischemia, and a protocol for stress-testing in the MR system has been developed which can detect the changes noninvasively in the anterior wall.
We need to extend the techniques to permit measurements in the posterior and inferior walls Work is underway to combine new MR detector technology with MR enhancement and image processing techniques to increase the signal-to-noise ratio (SNR), and thereby improve access of the technique to deeper regions in the heart.
• Proton MR studies of myocardial creatine
Creatine is an important metabolite produced with ATP from the dephosphorylation of PCr. The total creatine pool is represented in the proton MRS spectrum by the N-CH3 resonance at 3.0 ppm. Detection by proton MRS has the advantages of much higher SNR than detection of PCr by 31P MRS, owing to higher sensitivity and concentration. Currently we are studying the use of MRS measures of creatine as a possible index of viability of heart tissue following myocardial infarction.
Bottomley PA, Weiss RG. Noninvasive magnetic resonance detection of reatine depletion in non-viable infarcted myocardium. The Lancet 1998;351;714- 18.
• Perfusion-sensitive MRI
The development of techniques in MRI which may provide enhanced sensitivity to the image intensity of myocardial perfusion based on MR relaxation effects, specifically T1, are underway. The hope is that during ischemic stress and/or infarction image contrast can be improved to permit direct visualization of jeopardized/infarcted myocardium. Theoretical work on the fundamental nature of MR relaxation phenomena, the prominent source of MR image contrast, is also a continuing interest.
International Society of Magnetic Resonance in Medicine
1. Bottomley PA, Pope JM, Cornell BA. "A proton magnetic resonance study of the motion of cage water molecules in the clathrate hydrate of Xenon". Mol Phys 1976; 31: 1277-1281.
2. Holland GN, Bottomley PA. "A colour display technique for NMR imaging". J Phys. E: Sci. Instrum. 1977; 10: 714-716.
3. Andrew ER, Bottomley PA, Hinshaw WS, Holland GN, Moore WS, Simaroj C. "NMR images by the multiple sensitive point method: Application to larger biological systems". Phys Med Biol 1977; 22: 971-974.
4. Holland GN, Bottomley PA, Hinshaw WS. "19F magnetic resonance imaging". J Magn Reson 1977; 28: 133-136.
5. Hinshaw WS, Bottomley PA, Holland GN. "Radiographic thin section image of the human wrist by nuclear magnetic resonance". Nature 1977; 270: 722-723.
6. Bottomley PA, Hinshaw WS, Holland GN. "A computer driven photoscanner for medical imaging". Phys. Med. Biol. 1978; 23: 309-317.
7. Hinshaw WS, Andrew ER, Bottomley PA, Holland GN, Moore WS, Worthington BS. "Display of cross-sectional anatomy by nuclear magnetic resonance imaging". Brit J Radiol 1978; 51: 273-280.
8. Bottomley PA. "A technique for the measurement of tissue impedance from 1 to 100 MHz using a vector impedance meter". J Phys E: Sci Instrum 1978; 11: 413-414.
9. Bottomley PA, Andrew ER. "RF magnetic field penetration, phase-shift and power dissipation in biological tissue: Implications for NMR imaging". Phys Med Biol 1978; 23: 630-643.
10. Hinshaw WS, Andrew ER, Bottomley PA, Holland GN, Moore WS, Worthington BS. "Internal structural mapping by NMR Imaging". Neuroradiol 1978; 16: 607-609.
click here to see the entire publishcation list
Phone: 410.955.0366 FAX: ....410.614.1977 email: email@example.com
© Copyright 2005 | All Rights Reserved | Johns Hopkins University
600 North Wolfe Street, Baltimore, Maryland 21287 USA