Traumatic cervical spinal cord injury: relationship of MRI findings to initial neurological impairment.

Abstract

To quantify the degree of available space for the cord and cord swelling in patients following traumatic cervical spinal cord injury (TCSCI), and to assess the relationship among the available space for the cord, cord swelling, and the severity of neurological impairment. This study included 91 patients. The following indexes were measured by two blinded observers: maximum cord available area (CAA_max) and maximum cord swelling area (CSA_max). The American Spinal Injury Association (ASIA) impairment scale (AIS) grades were used to evaluate the extent of neurological injury. Relationship among CAA_max, CSA_max, and initial AIS grades was assessed via univariate and multivariate analyses. Patients who were AIS grade A (complete injury) demonstrated significantly greater median CAA_max and CSA_max than AIS grade C or D (incomplete injury) (P < 0.01). Multivariate analysis identified only CAA_max (OR 20.88 [95% CI 1.50-291.21]; P = 0.024) and CSA_max (OR 17.84 [95% CI 1.15-276.56]; P = 0.039) were identified as independently influencing the likelihood of complete injury at the initial assessment. The classification accuracy was best for CAA_max and CSA_max; areas under the curve were 0.8998 (95% CI 0.7881-1.0000) and 0.9167 (95% CI 0.8293-1.0000), respectively. The present study provides a novel radiologic method for identifying the severity of TCSCI with T2-weighted MRI findings. Greater available space for the cord (CAA_max > 38%) and cord swelling (CSA_max > 29%) can be used to identify patients at risk for TCSCI and both imaging characteristics are associated with an increased likelihood of severe neurological deficits. Diagnostic: individual cross-sectional studies with consistently applied reference standard and blinding.