DIAGNOSTIC-VALUE OF HIGH-DOSE CONTRAST-ENHANCED COMPUTED-TOMOGRAPHY OF THE POSTOPERATIVE LUMBAR SPINE

Objective: To evaluate the accuracy of high-dose intravenous contrast- enhanced computed tomography (CT) in differentiating recurrent herniat ed disk from scar tissue after lumbar spine surgery. Methods: Retrospe ctive review of postoperative constrast-enhanced lumbar CT scans obtai ned in 286 patients who had received 84.6 g of iodine intravenously. T he correlation between CT results and surgical findings was evaluated in 37 of the patients who underwent a subsequent repeat operation with in 12 weeks of the CT study. Results: In detection of recurrent hernia ted disk, the sensitivity of CT was 63.4%, its specificity was 75.0%, its positive predictive value was 95.5% and its negative predictive va lue was 20.0%. Conclusion: This study does not support the use of high doses of contrast medium administered intravenously in CT of the post operative lumbar spine; the results are not significantly different fr om those of previous reports involving lower doses of constrast medium .