Study design: A multicenter, retrospective study using computed tomographic and magnetic resonance imaging data to establish quantitative, reliable criteria of canal compromise and cord compression in patients with cervical spinal cord injury.
Objectives: To develop and validate a radiologic assessment tool of spinal canal compromise and cord compression in cervical spinal cord injury for use in clinical trials.
Summary of background data: There are few quantitative, reliable criteria for radiologic measurement of cervical spinal canal compromise or cord compression after acute spinal cord injury.
Methods: The study included 71 patients (55 men, 16 women; mean age, 39.7 +/- 18.7 years) with acute cervical spinal cord injury. Causes of spinal cord injury included motor vehicle accidents (n = 36), falls (n = 20), water-related injuries (n = 8), sports (n = 5), assault (n = 1), and farm accidents (n = 1). Canal compromise was measured on computed tomographic scan and T1- and T2-weighted magnetic resonance imaging, and cord compression at the level of maximum injury was measured on T1- and T2-weighted magnetic resonance imaging. All films were assessed by two independent observers.
Results: There was a strong correlation of canal compromise and/or cord compression measurements between axial and midsagittal computed tomography, and between axial and midsagittal T2-weighted magnetic resonance imaging. Spinal canal compromise assessed by computed tomography showed a significant although moderate correlation with spinal cord compression assessed by T1- and T2-weighted magnetic resonance imaging. Virtually all patients with canal compromise of 25% or more on computed tomographic scan had evidence of some degree of cord compression on magnetic resonance imaging, but a large number of patients with less than 25% canal compromise on computed tomographic scan also had evidence on magnetic resonance imaging of cord compression.
Conclusions: In patients with cervical spinal cord injury, the midsagittal T1- and T2-weighted magnetic resonance imaging provides an objective, quantifiable, and reliable assessment of spinal cord compression that cannot be adequately assessed by computed tomography alone.