Nanobiotechnology for health-care

The multi-component relaxation combination of proton magnetization in biological tissues magnetic resonance investigations 
Netreba A.V., Komarov A.O., Kyiashko Y.O.
Faculty of Radiophysics, Electronics and Computer Systems, Taras Shevchenko National University of Kyiv. Volodymyrska Street, 64/13, Kyiv-01601, Ukraine. 
E-mail: avn@univ.kiev.ua

The dynamics of the protons relaxation processes in the biological tissues MR imaging problem is considered. The response signal from the volume element is formed as components whose properties determine several types of biological tissues. Parameters of spin-spin and spin-lattice relaxation times depend on the singularities of the molecular local environment [1-2]. The calculation of the spin response signal is realized  as the sum of components from several types of brain tissue among which are white matter, gray matter and edema:
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where - proton density, T1 spin-lattice and T2- spin-spin relaxation times, TE, TR - times of the spin echo and pulse sequence duration. The method of the informativeness increasing for the properties study for individual regions is proposed. It is based on the response signal peculiarities formation due to the proton spin relaxation process under conditions of different tissues and pathology. No less significant result is the region separation and classification possibility accounting to spin relaxations for different biological tissues (Fig.1).
			
Fig. 1. MR image, histogram, boundaries  for biological tissues different types
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