IN-VIVO METHOD FOR DETERMINING AND IMAGING TEMPERATURE OF AN OBJECT/SUBJECT FROM DIFFUSION COEFFICIENTS OBTAINED BY NUCLEAR MAGNETIC RESONANCE

摘要

A method of determining and imaging the temperature or the temperature change of an object (human, animal, liquid or solid) by nuclear magnetic resonance of molecular diffusion coefficients is disclosed which includes placing the object in a magnetic field Bo at a temperature To, subjecting the object to a first series of magnetic resonance imaging sequences to obtain first numerical values or images of molecular diffusion coefficients Do for individual points of the object or of a limited volume thereof, changing the temperature to a temperature T of a part of the object measured in step (b), or waiting for a spontaneous change to said temperature, subjecting the object to a second series of magnetic resonance imaging sequences to obtain second numerical values or images of molecular diffusion coefficients D for individual points of the object or of a limited volume thereof, comparing point-by point the values of the diffusion coefficients Do allocated for the first series of diffusion images obtained in step (b) with the values of the diffusion coefficients D obtained in the second series of diffusion images in step (d) to determine and to generate a third series of values or images representing temperature changes dT between steps (b) and (d) for each individual point i of the object or of a limited volume thereof from the formula dTi = (kTo2/E) Log (D/Do)i wherein k is Boltzman's constant (1.38 10-23 J/K) and E is the activation energy (?0.2 eV at 20.degree.C), provided dT <