[Fat/water separation in the NMR tomogram. The imaging of bone marrow reactions in degenerative intervertebral disk changes].

We examined 410 patients with lumbar disc degeneration. In 23% fat suppressing IR sequences and phase contrast techniques displayed marrow reactions in subchondral bone adjacent to the affected discs. Only in some cases conventional MRI sequences were able to depict these marrow reactions. CT, plain X-ray and scintigraphy did not show marrow changes. Bacterial infection was excluded. Histological analysis showed substitution of haematopoietic marrow by fatty tissue, necrobiosis and increase in mucoid extracellular fluid.