Comparison between computed tomography-myelography and radioisotope-cisternography findings in whiplash-associated disorders suspected to be caused by traumatic cerebrospinal fluid leak.

STUDY DESIGN

A retrospective observational study.

OBJECTIVE

To investigate the traumatic cerebrospinal fluid (CSF) leak in whiplash-associated disorders (WADs) by comparing radioisotope-cisternography (RIC) and computed tomography (CT)-myelography (CTM) findings.

SUMMARY OF BACKGROUND DATA

WAD has been considered to be caused by traumatic CSF leak and termed as traumatic CSF hypovolemia. Several studies have reported that CSF leak was detected on RIC in the lumbosacral region of patients with WAD. However, recent evidence has indicated that RIC sometimes creates false-positive results by detecting nerve roots or cysts as CSF leak, whereas the appearance of contrast medium in the epidural space on CTM demonstrates CSF leak directly. So far there have been no data to compare the RIC and CTM findings in patients with WAD.

METHODS

RIC and CTM were performed on 36 patients with WAD, and the RIC and CTM findings were compared. In RIC, 37 MBq (111)In was injected, and paraspinal RI accumulation was evaluated as a direct sign of CSF leak. In CTM, 10 mL of iohexiol (240 mg I/mL) was infused via lumbar puncture, and multislice CT scan of the whole spine was acquired. Epidural collection of contrast medium, nerve root morphology, and cystic structures were investigated.

RESULTS

Paraspinal RI accumulation was observed in 19 patients on RIC, and it was located in the lumbosacral region in 18 patients. In contrast, no epidural collection was observed on CTM. CTM findings revealed that root sleeves and cystic structures were observed at the locations in which paraspinal RI accumulation was noted on RIC.

CONCLUSION

The results in this study indicated that traumatic CSF leak was not observed on CTM in patients with WAD, in whom CSF leak was suspected on RIC.