Magnetic resonance imaging of the spine. Normal anatomy.

Standard anatomy of the spine may be found in anatomy and radiology textbooks. However, there are aspects of spinal anatomy that are of particular importance to magnetic resonance imaging (MRI). The structure and orientation of the facet joints and their relationship to the neural foramina receive relatively little attention in standard anatomic works, but they are of great importance in evaluating nerve root compression syndromes. Similarly, the relationships between the cross-sectional diameters of the spinal canal, the subarachnoid space, and the spinal cord assume a great deal of significance when evaluating patients with signs or symptoms of spinal stenosis. Changes in the configurations and composition of the spinal cord will become increasingly important to the radiologists as it becomes possible to identify and distinguish spinal cord grey and white matter. Degenerative syndromes of the spinal cord may be more thoroughly evaluated once MRI permits identification of the specific regions or structures of the cord in which the tissue loss has been most severe.