The use of computed tomography to evaluate suspected mediastinal tumors

Evaluation of pulmonary and mediastinal masses

This article discusses the radiographic evaluation of pulmonary and mediastinal masses by the following modalities: plain radiography, fluoroscopy, conventional tomography, computed tomography, and magnetic resonance imaging. The author surveys digital and conventional angiographic techniques for assessing vascular masses within the thorax, and discusses the role of percutaneous needle biopsy of the thorax.

Unsuspected mediastinal hematoma diagnosed by computed tomography

A hemophiliac (factor VIII deficiency) was admitted with falling hematocrit after upper gastrointestinal bleeding. Computed tomography diagnosed a previously unsuspected large mediastinal hematoma. The use of CT in evaluating occult bleeding is discussed.

Lymphoma mimicking cardiomegaly

Images

Mediastinal computed tomography in myasthenia gravis

Thirty-six of 119 patients with myasthenia gravis examined by computed tomography for possible thymic mass had a thymectomy. The computed tomographic findings were compared to the findings of chest x-ray and linear tomography and then correlated with the surgical histopathologic results. Computed tomography detected all cases of thymoma or thymic enlargement due to hyperplasia. Chest x-ray correctly demonstrated 50% of thymomas present while linear tomography demonstrated 88%. Computed tomography was not able to distinguish between enlargement due to thymoma or hyperplasia unless calcification was present. The role of computed tomography is detailed and discussed in relationship to the other diagnostic modalities.

CT, including sagittal and coronal reconstruction, in the evaluation of pancoast tumors

Seventeen patients with histologically proved bronchogenic carcinoma involving the superior pulmonary sulcus (Pancoast tumors) were evaluated by computed tomography (CT), including sagittal and coronal image reconstruction. Compared to conventional radiography, axial transverse CT images provided, in all cases, additional information regarding local tumor extension and metastatic spread. Mediastinal involvement either by lymphangitic spread or direct tumor extension was present in 11 cases. In 4 patients plain films clearly showed mediastinal disease; however, CT more clearly delineated overall tumor extent, thus facilitating improved therapy planning. In a further 4 cases CT showed mediastinal involvement after plain films had been read as normal, and in an additional 3 instances metastatic involvement was either greatly underestimated (2 patients) or overestimated (1 patient) on the plain films. Reconstructed images in sagittal and coronal planes lacked detail but facilitated a three-dimensional concept of tumor extent and relationship of tumor to adjacent structures, particularly major blood vessels.

Misleading density of mediastinal cysts on computerized tomography

Five patients seen with roentgenographic evidence of smooth, rounded mediastinal masses were evaluated by computerized tomographic (CT) scanning. Density readings from the lesion were interpreted in all patients as being equivalent to solid tissue. With these findings, thoracotomy seemed necessary for definitive diagnosis. All 5 lesions were found to be thin-walled cystic structures containing thick viscid fluid. Contrary to views expressed in the radiology literature, we conclude that computerized tomography does not differentiate reliably between solid and cystic mediastinal masses.

Radiologic diagnosis of chest disease

Our purpose has been to provide a cursory review of radiologic diagnosis of noncardiac chest diseases. We have discussed several important diagnostic problems using illustrative cases from our experience. Although we have emphasized the role of computed tomography in solving particularly difficult problems, we still believe that most of the proven conventional techniques provide the best, simplest, and most economical approach to many problems in chest diagnosis. It is also apparent that the overall imaging management of the patient requires a multifaceted approach. The complexities of diagnosis and patient management more than ever require a comprehensive dialogue between radiologist and surgeon. The ultimate beneficiary as far as these technologies and improvements in communications between physicians are concerned is the patient.