Aim:Cervical spondylotic myelopathy (CSM) is a common spinal pathology characterized by increased signal intensity (ISI) differences on magnetic resonance imaging, prompting research into its prognostic implications. This retrospective multicenter study aimed to compare the preoperative and postoperative ISI outcomes of CSM patients who underwent posterior decompression and fusion, and to assess the correlation between ISI changes and postsurgical clinical prognosis.Material and Methods:The results from 123 patients were evaluated. In addition to demographic data, such as age and gender, factors, including body mass index (BMI); smoking history; duration of symptoms; follow-up periods; levels of decompression and fusion; comorbidities, such as diabetes, coronary artery disease, and hypertension; ISI grading; cervical sagittal vertical axis; C2-7 cervical lordosis parameters; and Modified Japanese Orthopedic Association (mJOA) scores, were statistically analyzed preoperatively and postoperativelyResults:ISI improved in 39 patients (31.7%), remained unchanged in 53 patients (latent, 43.1%), and deteriorated in 31 patients (25.2%). There were no statistically significant differences in terms of age, gender, BMI, or levels of decompression and fusion between patients with ISI improvement, latent ISI, and worsened ISI. Patients with ISI improvement had the highest postoperative C2-7 lordosis values and shortest duration of symptoms. There was no statistically significant difference in the mJOA scores between patients with and without ISI improvement.Conclusion:ISI improvement in CSM patients undergoing posterior cervical decompression and fusion is influenced by symptom duration and preoperative–postoperative cervical lordosis values. However, this study did not find a correlation between ISI improvement and clinical recovery based on the mJOA scores.