Role of CT scanning in the superior vena cava syndrome.

The value of computerized tomographic (CT) studies was compared to other imaging procedures in 18 consecutive patients with the superior vena cava syndrome (SVCS) during a 47-month period. Sixteen of these cases had proved malignancy. In addition to tumor masses, CT findings included effacement, compression, and displacement of the great vessels and the presence of thrombi and collateral blood flow. Significantly, tumor was demonstrated in the region of the superior vena cava in five patients in whom a definite mass could not be diagnosed by other means. CT scanning in a sixth case revealed that although mediastinal tumor was present it was not located in the immediate region of the occluded vessels. CT was corroborative and helpful in planning therapy in all but one of the remaining patients. CT scans appear to be of most value in cases of SVCS in whom other modalities cannot demonstrate tumor and, particularly, in excluding recurrent tumor in previously treated patients.