| Magnetic Resonance Electrical Impedance Tomography (MREIT) is a new functional imaging modality which combine the Magnetic Resonance Imaging(MRI)technique and Electrical Impedance Tomography(EIT) technique. The major advantage of MREIT is the high impedance resolution imaging and improvement of the ill-posed problem in conventional EIT. Through a thorough research of signal measurements and data acquisition methods in MREIT, a data collection system for MREIT based on this theory was designed and developed, which provided a foundation for future experiments research and reconstruction algorithm study. In this dissertation, the EIT hardware structures and the characters and design methods of the main function blocks were analyzed in detail at first, and a whole circuit of EIT data collection system is presented. The results of imaging experiment revealed the good performance of the system. Based on these results and the physical principles and present achievements in MREIT, the key point of the combination of MRI and EIT was described. Furthermore, we discussed the rigorous matching relationship between applying current and Spin Echo Sequence and presented a definite imaging sequence used in our system. Based on the permanent magnet MRI device, the hardware system scheme of MREIT was contrived. After analyzing the characters of bipolar current source, a realizable circuit triggered by hardware was devised. Meanwhile, the discussion of Electro Magnetic Compatibility of whole system was also given. At last, testing experiments using physical model were carried out, from which the magnetic flux density distribution and current density distribution were obtained. The image results showed the feasibility of the system. In order to reduce the RF shield effect generated by metal electrodes, we tested the electrodes with different material and configuration patterns. It was found that the carbon might be the best material for electrode in MREIT.
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