Magnetic Resonance Imaging Research Paper

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Magnetic Resonance Imaging (MRI) is the foundation of all the developed techniques, be it functional MRI (fMRI) or Susceptibility Weighted imaging (SWI), or Manganese enhanced MRI (MEMRI), or Magnetic Resonance imaging(MRS). MRI provides anatomical information (of brain), while fMRI or diffusion tensor Imaging (DTI) can visualize cortical networks within brain. SWI examines the vascular structures (blood vessels), MEMRI depicts cortical layers crucial information. A MRS, on which the further paragraphs would summarize is a technique used to contemplate Biochemistry of a tissue (neurotransmitters, high energy phosphates). MRS is often referred as Nuclear Magnetic Resonance Spectroscopy (NMR Spectroscopy). NMR spectroscopy is used to determine…show more content…
The gyromagnetic ratio(ϒ) would be different for each nuclei, hence Larmor frequency ω=ϒB (B is the magnetic field ) would be different. Accordingly, a different coil would be required. Clinical application of NMR spectroscopy includes, analyzing different brain metabolites values, investigating longitudinal metabolite changes associated with epileptogenesis in vivo in a rat model. The first application of in vivo spectroscopy was achieved by David Hoult in 1974 along with his colleagues. Another application could be sustained neuronal activation raises oxidative metabolism to a new steady-state level: evidence form 1H NMR spectroscopy in the human visual cortex. Protons has a tendency to absorb different frequencies in different environments. Consequently, they can be distinguished by NMR. NMR is nothing but an interaction of a radio frequency field and the nuclei of atoms in presence of external magnetic field (Bo). This ideology is derived from the spin properties of nuclei. Spin is stated as an angular momentum of a nucleus, which is accountable for the magnetic moment. When a…show more content…
It is used in a research setting to analyze metabolite dynamics in patients suffering from epilepsy, migraine and dyslexia. Some of the metabolites that are important and discussed in the class were N-acetyl asparate (NAA), Glutamate, Phosphocreatine (PCr), Creatine (Cr), Glycerophosphorylcholine (GPC), Phosphocholine (PC) and myo-Inositol. Chemical shift imparts structural information of a molecule. When a raw data is processed and converted to its structural information, it termed as assigning the spectrum. Since we divide a Hz signal by a MHz signal, we need to multiply the calculated value by million, to enhance it. Therefore, the spectrum depicts parts per million (ppm) on x-axis. In order to detect such minute frequency details, we require homogeneous field. Consequently, we use shimming coils, to adjust the homogeneity. Echo-planar-Imaging, a fast imaging technique is preferred during MRS. A scalar J-coupling is a phenomena which is mediated through chemical bonds connecting spins. For instance, in Adenosine Triphosphate (ATP), we can picture Alpha (α), Beta (β), Gamma (ϒ). Thus the frequency spectrum would represent, two frequency peaks for α, two peaks for ϒ, but three peaks for β. The reason being, β is in direct correlation to α & ϒ. Usually, the frequency difference in the peaks would be

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