146 Diffusion Tensor Imaging Metrics Correlate With Quantitative Tests of Physical Function in Cervical Spondylotic Myelopathy

• Published in: Neurosurgery Vol. 61; no. CN_suppl_1; pp. 207 - 208
• Main Authors: Wang, Marjorie C., Vedantam, Aditya, Schmit, Brian, Kurpad, Shekar N.
• Format: Journal Article
• Language: English
• Published: Philadelphia Oxford University Press 01.08.2014; Copyright by the Congress of Neurological Surgeons; Wolters Kluwer Health, Inc
• Subjects: Biomarkers; Neurosurgery
• ISSN: 0148-396X; 1524-4040
• DOI: 10.1227/01.neu.0000452420.83946.e1

Abstract INTRODUCTION: Diffusion tensor imaging is a magnetic resonance imaging technique that shows promise as a biomarker for disease severity and progression among patients with cervical spondylotic myelopathy (CSM). Prior work has shown correlations between diffusion tensor imaging (DTI) metrics and the modified Japanese Orthopaedic Association score (mJOA). However, the relationship between DTI and quantitative tests of physical function in CSM has not been previously studied. We hypothesized that DTI metrics would correlate with the 10-meter walk test, grip strength, and the 9-hole peg test. METHODS: We prospectively enrolled CSM subjects and obtained DTI images, the mJOA score, and the 10-meter walk test (average time of 3 trials); grip strength (average strength of 3 trials); and the 9-hole peg test (average time of 2 trials per dominant/nondominant hand). We used Spearman's rho to test the association between DTI metrics and the quantitative tests of physical function. Significance was set at P < .05. RESULTS: Eighteen subjects were enrolled and had DTI imaging, mJOA, the 10-meter walk test, and grip strength test. Of these, 7 also had the 9-hole peg test. The mean mJOA score was 13.1 (SD 1.8). The mJOA was not significantly correlated with our quantitative motor tests. DTI fractional anisotropy showed a trend towards correlating with mJOA (0.46, P = .06); 10 m-walk test (−0.42, P = .09); and grip strength (0.47, P = .05). DTI mean diffusivity significantly correlated with grip strength (−0.59, P = .01); and 9-hole peg test dominant and nondominant hand (0.96, P < .01 and 0.93, P < .01, respectively). CONCLUSION: In this pilot study, we found significant correlations between DTI mean diffusivity and upper extremity motor function, and a trend towards significant correlations between DTI fractional anisotropy and 10-meter walk test and grip strength. DTI metrics may be a biomarker for motor impairment in CSM and should be further studied in a larger number of subjects.