Prospective Analysis of Day-One Postoperative MRI Following Cervical Decompression for Cervical Myelopathy: Insights into Residual Compression and Signal Changes.

Background Cervical myelopathy is a progressive condition caused by spinal cord compression, often requiring timely surgical decompression. Although clinical improvement is generally expected after surgery, the role of immediate postoperative magnetic resonance imaging (MRI) in assessing decompression adequacy and predicting neurological recovery remains underexplored. This study examines the value of early postoperative MRI in identifying residual stenosis, missed levels, and intramedullary signal changes. Methods A total of 181 patients who underwent cervical decompression surgery for cervical spondylotic myelopathy (CSM) were prospectively included. Depending on the stenosis level, patients underwent posterior laminectomy with or without fusion, or anterior cervical discectomy/corpectomy. Preoperative and immediate postoperative MRI (within 24 hours) were evaluated for decompressed levels, residual stenosis, missed levels, and intramedullary T2 signal changes, graded using Chen's grading. All MRIs were independently reviewed by a neuroradiologist and cross-checked by the spine surgeon, both blinded to clinical status. Statistical analysis was performed using a paired t-test. Results Of the 181 patients, 125 had CSM and 40 had ossification of the posterior longitudinal ligament. The posterior approach was used in most cases due to multilevel involvement. Postoperative MRI showed persistent stenosis in seven patients, with early detection enabling timely intervention. Signal intensity changes were observed in 139 patients, with increased size and clarity in 121 cases. These changes in intramedullary signal intensity were statistically significant (p < 0.001). Four cases of missed-level decompression were identified and corrected during the same admission. Non-compressive hematomas were noted in 14 patients, and cerebrospinal fluid (CSF) collections in 12. In one patient, immediate postoperative MRI revealed persistent compression at the C1 level after C2-C7 laminectomy, requiring reoperation for adequate decompression. Conclusion Immediate postoperative MRI is valuable for confirming decompression adequacy, identifying residual compression, and detecting complications such as CSF leaks and hematomas. The transient increase in intramedullary signal changes underscores the need for further research on their progression and correlation with long-term neurological recovery. Routine postoperative MRI screening, particularly with limited sagittal sequences, can enhance patient safety, prevent delayed interventions, and potentially improve surgical outcomes. Future studies should explore long-term signal evolution and its relationship to clinical recovery, especially in thoracic myelopathy, where evidence remains limited.