Clinical correlates of high cervical fractional anisotropy in acute cervical spinal cord injury.
OBJECTIVE
Fractional anisotropy (FA) of the high cervical cord (C1-C2), rostral to the injury site, correlates with upper limb function in patients with chronic cervical spinal cord injury (SCI). In acute cervical SCI, this relationship has not been investigated. The objective of this study was to identify functional correlates of FA of the high cervical cord in a series of patients with acute cervical SCI.


METHODS
Traumatic cervical SCI patients who underwent presurgical cervical spine diffusion tensor imaging at our institution were reviewed for this study. FA of the whole cord as well as the lateral corticospinal tracts (CSTs) was calculated on axial images from C1-C2. Upper limb motor (C5-T1) and sensory (C2-T1) function scores were extracted from the admission American Spinal Injury Association (ASIA) examinations. Correlation analysis for FA with ASIA examinations was performed using a Pearson correlation.


RESULTS
Twelve subjects (9 men, 3 women; mean age 54.7 ± 4.0 years) underwent cervical spine diffusion tensor imaging at a mean duration of 3.6 ± 0.9 days postinjury. No patient had cord compression or intramedullary T2-weighted hyperintensities within the C1-C2 segments. FA correlated with upper limb motor score (whole cord: r = 0.59, P = .04; CST: 0.67, P = .01) and the ASIA grade (whole cord: r = 0.61, P = .03; CST: r = 0.71, P = .009). No correlation was found between FA and sensory scores.


CONCLUSIONS
FA of the whole cervical cord as well as the CST, rostral to the injury site, is associated with preserved upper limb motor function as well as superior ASIA grades after acute cervical SCI. FA of the high cervical cord is a potential biomarker of neural injury after acute cervical SCI.
Department of Neurosurgery, Medical College of Wisconsin, Milwaukee, Wisconsin, USA.
Aditya
A
Vedantam
Department of Neurosurgery, Medical College of Wisconsin, Milwaukee, Wisconsin, USA.
Gerald
G
Eckardt
Department of Neurosurgery, Medical College of Wisconsin, Milwaukee, Wisconsin, USA.
Marjorie C
MC
Wang
Department of Biomedical Engineering, Marquette University, Milwaukee, Wisconsin, USA.
Brian D
BD
Schmit
Department of Neurosurgery, Medical College of Wisconsin, Milwaukee, Wisconsin, USA. Electronic address: skurpad@mcw.edu.
Shekar N
SN
Kurpad
D000208:Acute Disease; D000328:Adult; D000368:Aged; D016880:Anisotropy; D066193:Cervical Cord / Q000293:injuries* / Q000473:pathology*; D056324:Diffusion Tensor Imaging; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009068:Movement; D009460:Neurologic Examination; D011712:Pyramidal Tracts / Q000293:injuries / Q000473:pathology; D012677:Sensation; D013119:Spinal Cord Injuries / Q000473:pathology* / Q000503:physiopathology; D034941:Upper Extremity / Q000503:physiopathology; D055815:Young Adult
Diffusion tensor imaging; Fractional anisotropy; Spinal cord; Spinal cord injury