Introduction: FA of the high cervical cord from diffusion tensor imaging (DTI) correlates with upper limb function in acute cervical cord injury. There is currently no objective, noninvasive biomarker to use in monitoring cervical spondylotic myelopathy (CSM). We investigated the correlation between FA of the high cervical cord and functional recovery at 12 and 24 months in patients that underwent decompressive surgery.
Methods: Patients scheduled for surgery received DTI scans pre-operatively. FA values of the whole cord at C1-C2 and the level of maximal compression (LMC) were calculated. Functional status was measured using the modified Japanese Orthopedic Association (mJOA) scale pre-operatively, and at 24 months. Regression analysis between FA and mJOA assessments was performed.
Results: 34 patients underwent decompressive surgery for CSM and were followed for 2 years at the Medical College of Wisconsin (Milwaukee, WI). Pre-operative FA correlated inversely with clinical recovery (based on mJOA scores) at 1 (p=0.003) and 2 years (p=0.11).
Conclusions: In this large longitudinal study, FA shows promise as a biomarker for improvement following surgery for myelopathy at 1 and 2 years out from the operation. FA may be a useful biomarker to determine functional outcome after surgical decompression in patients with myelopathy. It could further provide a basis to explain to patients their expected recovery following surgery.
Patient Care: This research exhibits the possibility of tracking not only the severity of CSM with an objective, noninvasive biomarker, but also the opportunity to predict and monitor post-operative improvement in appropriate surgical candidates.
Learning Objectives: By the conclusion of this session, participants should be able to:
1. To determine the usefulness of fractional anisotropy (FA) as a biomarker for the severity of CSM
2. To explore using objective biomarkers to predict improvement after decompressive surgery.
3. To compare objective vs. subjective methods of monitoring CSM