INTRAMEDULLARY CHANGES OF THE SPINAL-CORD IN CERVICAL SPONDYLOTIC MYELOPATHY

Study Design, This study retrospectively reviewed magnetic resonance i maging and delayed computed tomography after myelography of cervical s pondylotic myelopathy patients who needed surgical treatment. Objectiv es, The purpose of this study is to clarify the meaning of high magnet ic resonance intensity areas in cervical spondylotic myelopathy patien ts. Summary of Background Data. There is no conclusion whether the hig h magnetic resonance signal intensity areas can be a predictor for sur gical results or not. Methods, Thirty-one patients with cervical spond ylotic myelopathy were examined with magnetic resonance imaging before surgery and delayed computed tomography after surgery. The presence o r absence of high intensity areas in the spinal cord was compared with clinical symptoms and surgical outcomes. Results. Twenty-three (74%) of 31 patients showed high intensity areas in the spinal cord on the T 2-weighted image. Among these 23 patients, 18 revealed bilateral imtra medullary ''snake eyes'' enhancement in delayed computed tomography. T he presence of high intensity areas did not correlate with the surgica l outcomes. Patients with multisegmental (linear) high intensity areas frequently manifested muscle atrophy in upper extremities. Conclusion s. High intensity areas on T2-weighted magnetic resonance imaging were not correlated with the severity of myelopathy or surgical outcomes e valuated by the Japanese Orthopaedic Association score. Magnetic reson ance imaging or delayed computed tomography in this study could not ru le out the presence of white matter changes, including axonal loss or demyelination. Multisegmental (linear) high intensity areas on T2-weig hted magnetic resonance imaging were associated with clinical evidence of extensive anterior horn cell and radiographic evidence of gray mat ter cavitation.