Sequential MRI studies in patients with cervical cord injury but without bony injury.

Sequential magnetic resonance imaging (MRI) of 23 patients who suffered cervical spinal cord injury without bony injury was performed prospectively. The major cord injury detected by MRI was at the C3-4 disc level in 16 patients (70%). Three patterns of signal changes were observed. Enhancement of the injured cord was observed on Gd-DTPA-enhanced MRI in 10 patients and the palsy of these patients was more severe than that of those without enhancement. Enhancement was recognized about 2 weeks earlier than the signal change (from isointense to low intensity) on T1-weighted images. This enhancement might represent necrosis, absorption, and reorganisation of the spinal cord, and appears to be a sign of a poor prognosis or an indication that damage is permanent. Another characteristic imaging finding was a vague high intensity signal in the dorsal column of the spinal cord extending rostrally from the main lesion, which appeared 2-3 months after injury and disappeared around 6 months. This finding represents Wallerian degeneration of the corticospinal tract in the cervical cord. Rigidity of the legs and sensory changes of the fingers became more prominent during this period.