The overall goal of this project is to understand and exploit the macroscopic effects of microscopic susceptibility variation in Nuclear Magnetic Resonance (NMR) imaging. Microscopic variations in local magnetic fields can produce large changes in NMR image contrast. We seek to understand quantitatively a broad range of sources of this susceptibility contrast: effects of the distribution of targettable, nano-sized superparamagnetic particles; intra- and extravascular effects of deoxyhemoglobin in cardiac vasculature; and the use of these phenomena for quantifying non- invasively the distribution of vessels size in vivo. We combine Monte Carlo random walk simulations and experimental studies in animal models in order to define and probe both our understanding of susceptibility contrast, as well as our ability to exploit this understanding for physiological measurement.

National Institute of Health (NIH)
National Cancer Institute (NCI)
Research Program Projects (P01)
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Massachusetts General Hospital
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Dijkhuizen, Rick M; Singhal, Aneesh B; Mandeville, Joseph B et al. (2003) Correlation between brain reorganization, ischemic damage, and neurologic status after transient focal cerebral ischemia in rats: a functional magnetic resonance imaging study. J Neurosci 23:510-7
Dijkhuizen, Rick M; Asahi, Minoru; Wu, Ona et al. (2002) Rapid breakdown of microvascular barriers and subsequent hemorrhagic transformation after delayed recombinant tissue plasminogen activator treatment in a rat embolic stroke model. Stroke 33:2100-4
Atalay, M K; Poncelet, B P; Kantor, H L et al. (2001) Cardiac susceptibility artifacts arising from the heart-lung interface. Magn Reson Med 45:341-5
Dijkhuizen, R M; Ren, J; Mandeville, J B et al. (2001) Functional magnetic resonance imaging of reorganization in rat brain after stroke. Proc Natl Acad Sci U S A 98:12766-71
Dijkhuizen, R M; Asahi, M; Wu, O et al. (2001) Delayed rt-PA treatment in a rat embolic stroke model: diagnosis and prognosis of ischemic injury and hemorrhagic transformation with magnetic resonance imaging. J Cereb Blood Flow Metab 21:964-71
Schellingerhout, D; Rainov, N G; Breakefield, X O et al. (2000) Quantitation of HSV mass distribution in a rodent brain tumor model. Gene Ther 7:1648-55
Marota, J J; Ayata, C; Moskowitz, M A et al. (1999) Investigation of the early response to rat forepaw stimulation. Magn Reson Med 41:247-52
Mandeville, J B; Marota, J J; Ayata, C et al. (1999) Evidence of a cerebrovascular postarteriole windkessel with delayed compliance. J Cereb Blood Flow Metab 19:679-89
Sanchez del Rio, M; Bakker, D; Wu, O et al. (1999) Perfusion weighted imaging during migraine: spontaneous visual aura and headache. Cephalalgia 19:701-7
Poncelet, B P; Koelling, T M; Schmidt, C J et al. (1999) Measurement of human myocardial perfusion by double-gated flow alternating inversion recovery EPI. Magn Reson Med 41:510-9

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