Mediastinal tumors: sensitivity of detection with sonography compared with CT and radiography

The purpose of this prospective study was to evaluate the sensitivity of mediastinal sonography compared with computed tomography (CT) and chest radiography in the detection of mediastinal tumors. The sonograms, CT scans, and chest radiographs of 182 patients were interpreted blindly by three observers, and the results were compared. The proportion of diagnostic sonographic examinations varied for the different mediastinal compartments from 85% (subcarinal region) to 96% (supraaortic region). The sensitivities of sonography and chest radiography, respectively, for each compartment, with CT as the reference method, were as follows: supraaortic region, 98% and 67%; paratracheal region, 89% and 69%; aorticopulmonary window, 81% and 62%; prevascular region, 92% and 46%; subcarinal region, 69% and 31%; pericardial region, 100% and 67%; posterior mediastinum, 6% and 6%; and paravertebral region, 11% and 44%. These results show that sonography is superior to chest radiography in the diagnosis of mediastinal tumors. In certain mediastinal regions (supraaortic, pericardial, prevascular, and paratracheal), sonography is so sensitive that CT and magnetic resonance examinations may be obviated in patients with equivocal radiographic findings.