CT myelography in cervical nerve root avulsion.

Computed tomographic myelography (CTM) with metrizamide was performed in six patients to delineate the CTM appearance of avulsed cervical nerve roots. Twelve cervical nerve root avulsions were found and confirmed by cervical myelography and physical examination. The CTM findings in cervical nerve root avulsion closely matched those found myelographically: outpouchings of metrizamide extending ventrolaterally from the thecal sac into the neural foramen in an expanding or "mushroom-like" manner and separated from the thecal sac proximally by a 1-2 mm thick dural plane. This CTM appearance differs from that seen in such normal variants as dilated nerve root sleeves or root diverticula. We conclude that CTM is as sensitive as myelography. In addition, it can provide useful information regarding bony fragments or contiguous soft tissue injury.