13 patients were examined for cervical spondylotic myelopathy by postoperative magnetic resonance imaging. All patients were male and the operative procedure was open door laminoplasty. On the saggital scans, a low or high signal intensity lesion within the spinal cord, the distance from the posterior edge of the vertebral body to the spinal cord and spinal atrophy were investigated their relationship with the JOA score improvement rate was analyzed. On T2-weighted scans, a high signal intensity loesion was observed in 5 cases. And 2 of them had a low signal intensity lesion on T1-weigthed scans.
Postoperative results of patients with T2 high signal intensity lesions were poor and their mean improvement rate was 18.4%, while those without T2 high signal intensity was 64.7%. There was a relationship between distance and improvement rate of those without T2 high signal intensity lesions. We concluted that the T2 high signal intensity lesion and the distance from the posterior edge of the vertebral body to the spinal cord carry prgnostic significance in postoperative magnetic resonance imaging.