The Research Of MRI Multifunctional Quality Control Phantom

Magnetic resonance equipment is widely used in medical diagnosis with its special imaging features.As an important basis for diagnosis,especially for treatment planning,MRI requires higher spatial precision and accuracy of the images produced by the scanning device.At present,quality control phantom is mostly used to monitor the performance of the magnetic resonance equipment.However,existing phantoms have limited characteristics and relative deficiencies.The purpose of this study is to design a multifunction quality control phantom of MRI,quantitatively detect the influence of scanning system on geometric errors of static structure imaging and spatial accuracy of blood flow,and then evaluate the spatial accuracy of imaging equipment,so as to provide research basis for the subsequent image registration.Based on the requirements for clinical quality control,the phantom system with a fluid phase structure in this paper was built according to the quality control standards of MRI and human body structure characteristics,and the key technological schemes such as processing,measurement and assembly were formulated and verified through implementation,making the spatial accuracy far higher than the resolution requirements of magnetic resonance equipment.Then the clinical experiment plan was designed.The processing method of trials data was developed.The image was evaluated and analyzed.Finally,the spatial accuracy of the imaging equipment was comprehensively evaluated.The specific work in this paper is as follows:The static module was designed and validated according to the magnetic resonance quality control standards.After preprocessing the images obtained from the experiment,extracting features,and the geometric distortion was quantitatively calculated and corrected.Moreover,the geometric distortion of MRI and the validity of the correction method were also explored and analyzed.Meanwhile,error reference for image registration was provided.The dynamic module was designed to explore the accuracy and reliability of the dynamic imaging quality of the scanning system under different settings(coding direction,coding rate,fluid flow direction,fluid velocity,etc.).The composite module was designed to explore the imaging effect of magnetic resonance equipment for high simulation structure,and provide a new idea for phantom to achieve the advanced demand of the "human-simulated".The key characteristics were found according to the characteristic parameters of MRI quality of each module.Based on the objective indicators such as geometric fidelity and fluid fidelity,the comprehensive evaluation scheme of MRI was finally formulated and corresponding report was formed.The test results show that the distortion error of experimental images can be detected by the system.The accuracy of the test results can be guaranteed to a certain extent by quantitatively detecting and correcting the space geometric distortion of MRI and seeking for the best optimal dynamic imaging settings,which provides an effective and accurate auxiliary basis for radiotherapy planning and clinical diagnosis of cardiovascular diseases.Therefore,the research can comprehensively analyze the imaging performance of magnetic resonance equipment and lay the foundation for the clinical quality inspection work.