Method for obtaining contrast agent relaxation time

Abstract

The invention relates to a method for obtaining contrast agent relaxation time. The method comprises the following steps: automatically identifying a contrast agent sample in an image, precisely positioning a sample center point, and calculating the radius of a sample test tube, automatically selecting ROI (Region of Interest) by the center point of the test tube as the center according to the radius of the test tube, calculating the mean value of a pixel signal in the ROI, and experimenting a standard deviation; and finally, carrying out nonlinear fitting to an automatically-extracted signal, and accurately, quickly and efficiently calculating a spinning-lattice relaxation time T1 value and a spinning-lattice relaxation time T2 value of the contrast agent. A process that a plurality of samples are identified in the image and the ROI of the samples is selected is a computer automation process, an artificial process is omitted, and the positioning accuracy, the ROI shape consistency and the result accuracy of the invention are far better than those of a traditional method. The whole flow from ROI selection and ROI signal extraction to the nonlinear fitting is a fully-automatic process, and the time efficiency of the method is far higher than the time efficiency of the traditional method.

Description

technical field [0001] The invention relates to the field of magnetic resonance imaging, in particular to a method for automatically extracting signals in magnetic resonance contrast agent imaging and using them to fit and calculate the delay time of contrast agents. Background technique [0002] Image contrast in MRI reflects the difference in signal intensity between two tissues, and contrast enhancement is the process of changing the signal intensity. Contrast agents, also known as contrast agents (Contrast agents), are agents that can change the physical properties of tissues, thereby affecting physical parameters and enhancing image contrast. Magnetic resonance contrast agents alter image contrast by altering the local magnetic environment of tissue. In magnetic resonance imaging, the magnetic resonance signals generated by protons and their spin-lattice relaxation time (longitudinal relaxation time) T1 and spin-spin relaxation time (transverse relaxation time) T2 dete...

AI Technical Summary

Problems solved by technology

[0008] The present invention aims at the problems of time-consuming, low efficiency, and subjectivity in obtaining contrast agent delay time in current image processing methods, and proposes a method for obtaining contrast agent delay time, which can automatically identify contrast agent samples in images, accurately Locate the center point of the sample to calculate the radius of the sample test tube, and automatically select the ROI based on the center point of the test tube according to the radius of the test tube, calculate the average value of the pixel signal in the ROI, and the experimental standard deviation

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