Resting-state brain plasticity is associated with the severity in cervical spondylotic myelopathy

Abstract

Objective: To investigate the brain mechanism of non-correspondence between imaging presentations and clinical symptoms in cervical spondylotic myelopathy (CSM) patients and to test the utility of brain imaging biomarkers for predicting prognosis of CSM.

Methods: Forty patients with CSM (22 mild-moderate CSM, 18 severe CSM) and 25 healthy controls (HCs) were recruited for rs-fMRI and cervical spinal cord diffusion tensor imaging (DTI) scans. DTI at the spinal cord (level C2/3) with fractional anisotropy (FA) and degree centrality (DC) were recorded. Then one-way analysis of covariance (ANCOVA) was conducted to detect the group differences in the DC and FA values across the three groups. Pearson correlation analysis was then separately performed between JOA with FA and DC.

Results: Among them, degree centrality value of left middle temporal gyrus exhibited a progressive increase in CSM groups compared with HCs, the DC value in severe CSM group was higher compared with mild-moderate CSM group. (P < 0.05), and the DC values of the right superior temporal gyrus and precuneus showed a decrease after increase. Among them, DC values in the area of precuneus in severe CSM group were significantly lower than those in mild-moderate CSM and HCs. (P < 0.05). The fractional anisotropy (FA) values of the level C2/3 showed a progressive decrease in different clinical stages, that severe CSM group was the lowest, significantly lower than those in mild-moderate CSM and HCs (P < 0.05). There was negative correlation between DC value of left middle temporal gyrus and JOA scores (P < 0.001), and the FA values of dorsal column in the level C2/3 positively correlated with the JOA scores (P < 0.001).

Conclusion: Structural and functional changes have taken place in the cervical spinal cord and brain of CSM patients. The Brain reorganization plays an important role in maintaining the symptoms and signs of CSM, aberrant DC values in the left middle temporal gyrus may be the possible mechanism of inconsistency between imaging findings and clinical symptoms. Degree centrality is a potentially useful prognostic functional biomarker in cervical spondylotic myelopathy.

Keywords: Brain plasticity; Cervical spondylotic myelopathy; Degree centrality; Resting-state functional magnetic resonance imaging.

Fig. 1

A flowchart of data processing. (a) sagittal T2WI MR image of a patient with CSM; (b) rs-fMRI data; (c): weighted connectivity matrix; (d) DC differences; (e) transverse T2WI MR image; (f) FA of the proximal spinal cord; (g) probabilistic maps of the lateral corticospinal tracts (blue) and dorsal columns (yellow) following registration to the SCT atlas

Fig. 2

Differences of FA in spinal white matter fiber tracts at C2-3 level of the subjects. Abbreviations CST-corticospinal tract; SHT-spinothalamic tract; **-p < 0.01; *p < 0.05

Fig. 3

DC differences between mild-moderate, severe patients and healthy controls

Fig. 4

Correlation analysis between JOA score and dorsal column FA value at level of C2/3 in CSM patients

Fig. 5

Correlation analysis between JOA score and DC value of left middle temporal gyrus

Fig. 6

The ROC curves of the DC values for the prediction of severity of CSM

Fig. 7

The ROC curves of the FA values for the prediction of severity of CSM