Accidental spinal cord injection of contrast material during cervical myelography with lateral C1-C2 puncture.

A 64-year-old woman was admitted to our hospital with slowly increasing paresis of the extremities. Because an intramedullar tumor was suspected, cervical myelography with lateral puncture of C1-C2 was performed. A 22-gauge needle was used, and normal return of clear, colorless spinal fluid was seen. During the uneventful injection of Omnipaque (iohexol, 240 mg I/ml), a longitudinal stripe of contrast medium was observed centrally in the cervical canal in the C1-C2 area (Fig. 1A). Injection into the spinal cord was suspected, and the injection was stopped immediately, after approximately 8 ml of contrast medium had been injected. The patient did not complain of pain or any other side effects during or after the injection. A subsequent CT examination (Fig. 1 B) suggested that the contrast medium had been injected into a syrinx with an open connection to the subarachnoid space. MR with 5-mm slices and T1and T2-weighted images 1 week later did not show any syrinx or other abnormality within the cord (Fig . 1 C). We therefore concluded that an injection into the spinal cord had taken place after all . The amount of contrast material injected into the cord was estimated to be about 1-2 ml [5, 6]. After the myelography, no additional neurologic deficits could be found . The final clinical diagnosis was degenerative myelopathy.