MEDIASTINITIS FOLLOWING MEDIAN STERNOTOMY - CT FINDINGS

PURPOSE: To evaluate the usefulness of computed tomography (CT) in the diagnosis of mediastinitis following median sternotomy. MATERIALS AND METHODS: Fifty patients aged 6 weeks to 80 years (31 male, 19 female) who underwent CT for clinically suspected mediastinitis following med ian sternotomy were retrospectively identified. CT scans were evaluate d for primary findings (localized mediastinal fluid, pneumomediastinum , or both) versus secondary or other findings (mediastinal edema, aden opathy, pleural effusion, or a sternal or lung abnormality). Patients were divided into three groups on the basis of the CT findings and fin al clinical diagnosis: those with primary CT signs and a final diagnos is of mediastinitis, those with primary CT signs of mediastinitis and a different final diagnosis, and those with neither primary CT finding s nor a final diagnosis of mediastinitis. RESULTS: All patients with c linical mediastinitis had primary CT findings. These patients underwen t CT an average of 24 days after surgery. Patients with primary CT fin dings and a final clinical diagnosis of something other than mediastin itis underwent CT an average of 9 days following surgery. Through post operative day 14, CT had a sensitivity of 100% for clinical mediastini tis but a specificity of 33%; after postoperative day 14, the sensitiv ity was 100% and the specificity was 100%. CONCLUSION: Primary CT find ings are not specific for mediastinitis through postoperative day 14; after day 14, they are highly indicative of mediastinitis.