[Intramedullary high intensity lesion on T2-weighted MR images in compressive cervical myelopathy]

Magnetic resonance (MR) imaging was performed in 147 patients with compressive lesion of the cervical spinal canal. Intramedullary high intensity lesions were observed on T2-weighted or proton density spin-echo images in patients with cervical spondylotic myelopathy (20.0%) and ossification of the posterior longitudinal ligament of the cervical spine (25.7%), while such signal abnormality was not found in patients with cervical spondylotic radiculopathy. Frequency of this finding was proportional to clinical severity of myelopathy and degree of spinal cord compression. The pathophysiological basis of such signal abnormality was presumed to vary from acute edema to chronic myelomalacia. In most cases showing intramedullary high intensity lesion, the spinal cord was compressed at multiple levels, but the high intensity was usually found at a single level where the compression was maximum. There was a good correlation between the neurological level and the high intensity level on MR images. Thus the intramedullary lesion on MR images is considered to be the main site of lesion responsible for the neurological symptom.