DIURNAL FLUID CHANGES OF LUMBAR DISKS MEASURED INDIRECTLY BY MAGNETIC-RESONANCE-IMAGING

The feasibility of magnetic resonance imaging and the magnetization tr ansfer technique for measurement of diurnal fluid changes in lumbar di scs was studied with the use of 13 healthy subjects. The diurnal heigh t loss of the subjects ranged from 13 to 21 mm. The disc signal in T-2 -weighted magnetic resonance imaging increased as much Bs 25% after ov ernight bed rest, presumably due to the enhanced influx of water. The change in magnetization transfer parameters also suggested increased h ydration of the disc after bed rest. Magnetic resonance imaging techni ques can be used for indirect measurement of the changes in fluid cont ent and the interaction of water with macromolecules in the disc.