Magnetic resonance image-forming temperature measurement method based on three-dimensional steady state free precession

Abstract

The invention relates to a magnetic resonance imaging temperature measuring method on the basis of three-dimensional free motion, comprising the steps as follows: 1) at initial temperature Tb, the repeating time TR, the temperature coefficients a and b, large turnover angle Alpha1 and small turnover angle Alpha 2 of the three-dimensional stable free motion sequence are determined; 2) images I and I of tissue to be measured are collected so as to gain the superposition images Ib=I+I of the tissue to be measured at the initial temperature Tb; 3) at the to-be-measured temperature Th, under the conditions of temperature coefficient Alpha1 and repeating time T determined in the step 1), the image I of the tissue to be measured is collected; subsequently, under the conditions of temperature coefficient Alpha2 and repeating time T, the image I of the tissue to be measured is collected so as to gain the image I=I+I at the to-be-measured temperature Th of the tissue to be measured; 4) standard image I=Ih / Ib is superposed; 5) the temperature image I of the tissue to be measured is calculated; the value of each point on the temperature image I is the Delta T of the tissue to be measured at the point; 6) the to-be-measured temperature Th equal to Tb+Delta T of the tissue to be measured is worked out.

Description

technical field [0001] The invention relates to a biological tissue temperature measurement method, in particular to a magnetic resonance imaging temperature measurement method based on three-dimensional steady-state free precession. Background technique [0002] Tumor hyperthermia techniques such as radiofrequency ablation (RFA) and high-intensity focused ultrasound (HIFU) have become very promising tumor treatment methods. The tissue temperature distribution in the treatment area is an important parameter that directly determines the effect of hyperthermia. Real-time and accurate deep non-invasive temperature measurement is a key technology that currently restricts the further development of tumor hyperthermia. In recent years, the use of magnetic resonance imaging (MRI) for non-invasive temperature measurement is receiving more and more attention. Because under the action of the magnetic field in the magnetic resonance system, the change of tissue temperature will cause ...

AI Technical Summary

Problems solved by technology

[0016] The 3D-SSFP sequence is very sensitive to the uniformity and stability of the main magnetic field, so the uniformity of the magnetic field is not good or unstable, especially the inherent characteristics of the permanent magnet in the permanent magnetic resonance imaging system lead to the uniformity of the magnetic field generated by it. The intensity is not very high, and this magnetic field will change its magnetic field uniformity due to changes in ambient temperature or device heating, etc.

There is currently no effective solution

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