The Research Of MRS Post-Processing Methods And Realization

The clinical value of Magnetic Resonance Spectroscopy (MRS) is providing quantitative analysis to the obtained spectrum. Since the spectrum transformed from the FID which is acquired by the MR equipment via a FFT directly can not be used for clinical referencing, only after a series of Post-Processing applying to the spectrum it can be the reference to the clinical diagnosis. Recently, MRS software package has been configured as standard function in most heigh-field MRI system. Therefore, it is one of important taskes that provide MRS software package in our 1.5T scanner.This paper discusses and expounds some methods of phase correction and eddy current correction, and it mainly describes the advantages and weaknesses of such algorithms of phase correction and eddy current correction. At beginning it gives a brief overview about basics of MRI and MRS, and the common post-processing technologies and procedure of MRS. After that, four methods of phase correction, Ernst integral, DISPA line shape, PAMPAS simple integral and entropy minimization, and zero order eddy current correction are described with mathematics of these algorithms. The first two algorithms of phase correction are realized in this paper. Based on lots of experiments, this paper has discussed the results of these algorithms. And also, this paper describes the realization of the data acquisition software and the post-processing software based on the Superstar software system. During the developing of the software, the UML symbols are used to analyse the system and describe the system. This paper also describes the benefit of OO method using UML in software developing. To describe the software architecture, the Business Model, Requirements Specification, System Use Case and Sequence Diagram of the software are given in this paper. At last, some codes of the software are given to demonstrate the design and coding phase.Based on the result of experiment, the two algorithms of phase correction realized in this paper achieve the requirements of spectrum phase correction commendably. Because of our 1.5T scanner can not provide fid data with eddy current now, the ECC algorithm can not be verify now. The software business model, requirements, design and analysis meet the user requirements completely, and they can be used to our 1.5T scanner.