Wicklow K, Kolem H, Schneider M, Sauter R
Siemens AG, Bereich Medizinische Technik, Erlangen.
Aktuelle Radiol. 1993 Mar;3(2):90-9.
MR Spectroscopy offers the unique possibility of monitoring the metabolism of various organs non-invasively. Using examples of 1H and 31P MR spectra, experimental and commercially available techniques are presented and evaluated with regard to their potential clinical application. An example of a 1H human brain spectrum with a pathological lactate level illustrates the requirements for MRS examinations in terms of spatial and spectral resolution. STEAM, Spin-Echo, and Chemical Shift Resolved Imaging (CSI) techniques for 1H MRS are compared. In the field of 31P MRS, typical CSI spectra of the brain and liver are presented. First experimental results with a new double-oblique 3D-CSI technique for measurement of PCr/ATP ratios of different anatomical regions of the human heart are shown. The advantages of using double-resonance techniques for Nuclear Overhauser Enhancement (NOE) and decoupling are shown by the example of the phosphodiesters of the liver. The energy metabolism of skeletal muscle under exercise is resolved with 5 sec/spectrum, showing breakdown and synthesis of photocreatine (PCr) and inorganic phosphate (Pi). Appropriate instrumentation and technique are available to many clinics today; great interest now is directed towards the diagnostic value of MRS for certain indications.
磁共振波谱学提供了无创监测各种器官代谢的独特可能性。以氢质子(1H)和磷-31(31P)磁共振波谱为例,介绍了实验技术和商用技术,并对其潜在的临床应用进行了评估。一个具有病理性乳酸水平的氢质子人脑波谱示例说明了磁共振波谱检查在空间和波谱分辨率方面的要求。比较了用于氢质子磁共振波谱的激励回波采样法(STEAM)、自旋回波和化学位移分辨成像(CSI)技术。在磷-31磁共振波谱领域,展示了典型的脑和肝脏的化学位移分辨成像波谱。展示了使用一种新的双斜三维化学位移分辨成像技术测量人体心脏不同解剖区域磷酸肌酸/三磷酸腺苷(PCr/ATP)比率的初步实验结果。以肝脏的磷酸二酯为例,展示了使用双共振技术进行核Overhauser效应(NOE)和去耦的优势。以每秒5次波谱的速度解析了运动状态下骨骼肌的能量代谢,显示了磷酸肌酸(PCr)和无机磷酸(Pi)的分解与合成。如今许多诊所都具备合适的仪器设备和技术;目前人们对磁共振波谱在某些适应症方面的诊断价值非常感兴趣。