Study on Non-Invasive Assessment of Multiple Organ Function with In vivo ^<31>P-MRS

利用全身磁共振成像装置，研究了移植物在体内的功能评价方法。首先，用^<31>P-MRS测定灌注猪肝中的磷化合物。在本实验中，由于灌注不足，只能观察到无机磷酸盐、PME、PDE和NADH。然后，我们观察了杂种狗离体肝脏在人工心肺机灌注过程中的磷化合物。在本实验中，可以观察到高能磷酸盐（HEP），提示器官内HEP水平受灌注流量的影响。在第二个实验中，在指定感兴趣区域（DRESS方法）后，将体内^<31>P-MRS应用于人类肝脏。本实验观察了肝脏的特异光谱。根据这一发现，我们在肝脏手术前对患者进行了体内^<31>P-MRS试验，发现肝硬化肝脏和癌变肝脏的频谱存在差异。这一结果表明，体内P-MRS（<31>）是一种更有效的方法，可用于供体肝脏采集前的功能评估。利用实验核磁共振仪（6.4T），我们获得了体内mrs评价的一些基本数据，研究了离体大鼠心脏冷藏期间核磁共振光谱随温度的变化。因此，如果对T_1时间和探针灵敏度变化的影响进行校正，则可以对不同温度下获得的光谱进行比较。根据这一发现，我们对威斯康辛大学的解决方案进行了评估，发现了它的实用性。此外，我们研究了热缺血灌注肝脏中磷酸盐的代谢，并比较了生化法（HPLC）测定的HEP和核磁共振法测定的HEP。研究了异位犬心脏移植模型的组织血流量、导管压容曲线及电镜病理评价。这些数据可作为体内磁共振测量的基础数据。少

Using a whole body MRI device, we investigated functional evaluation method of a graft in vivo. First of all, phosphorus compounds in perfused pig livers were measured with ^<31>P-MRS. In this experiments, only inorganic phosphate, PME, PDE and NADH could be observed, because perfusion was not sufficient. Then, we observed phosphorus compounds during perfusion by artificial heart-lung machine in livers isolated from mongrel dogs. In this experiment, high-energy phosphates (HEP) could be observed, and it was suggested that HEP levels in organs are affected by perfusion flow.In the second experiment, in vivo ^<31>P-MRS was applied for human livers, after designation of regions of interest (DRESS method). In this experiment specific spectrum of the liver were observed. Following this finding, we tried in vivo ^<31>P-MRS in patients before liver operation and found different spectra between cirrhotic liver and cancer-affected livers. This result indicates that the in vivo ^<31>P-MRS is use … More ful method for functional evaluation of the donor liver before harvesting.Using an experimental NMR device (6.4T), we obtained several basic data for evaluation of in vivo MRS. Changes of spectrum in NMR depending on temperatures were studied in isolated rat hearts for cardiac viability during cold storage. As a result, the spectra obtained at different temperatures could be compared to each other if they are corrected for the influence from changes in T_1 time and probe sensitivity. Following this finding, we assessed the University of Wisconsin solution on isolated rat hearts and found its usefulness. Furthermore, we studied metabolism of phosphates during warm ischemia of perfused livers, and compared the HEP determined by a biochemical method (HPLC) and the HEP determined by NMR.And, we studied tissue blood flow, pressure volume curves with a conductance catheter and electromicroscopic pathologic assessment in heterotopic dog heart transplantation model. These data may applied for basic data of in vivo MRS measurements. Less