Effectiveness of CT in evaluating intrathoracic masses.

To compare the effectiveness of computed tomography (CT) with conventional radiography and conventional tomography for evaluating masses in the thorax, 168 masses, 154 of which were histologically verified, which had been examined with CT were reviewed. In 74 instances (44%) CT provided important additional information compared with conventional radiography. Compared to conventional tomography, CT added important information in 15 (23%) of 65 cases. In no case did CT fail to demonstrate pathology shown with the other two methods. Average radiation dose to the chest was 1.3 rad (0.013 Gy) with CT and 0.4 rad (0.004 Gy) with linear tomography. Although CT is associated with slightly greater radiation dose and cost, this review indicates it should be performed directly after plain film examination instead of conventional tomography when further investigation of an intrathoracic mass is indicated.