[Computed tomography in thoracic pathology]

The fundamental principles of computed tomography (CT), its clinical applications and costs are presented followed by the indications and results in diseases of the mediastinum, the oesophagus, heart and great vessels, and the lung and pleura. The CT scan can give the precise localization and density of mediastinal tumours and be used to distinguish thymomas, goiters, lymph nodes, lymphomas, neurinomas and different bronchogenic and pleuropericardial cystic formations. The operability of oesophageal cancer can also be determined. In cardiovascular diseases, the CT scan is particularly useful to identify inborn anomalies, aneurysms, aortic dissection or caval compression or thrombus formation. In lung diseases, the indications for a CT scan are particularly important in bronchopulmonary cancer, tuberculosis, bronchopathies and chronic lung diseases. In bronchogenic cancer, for example, the CT scan is not only a major diagnostic tool but is also particularly useful in determining the prognosis and for following the effectiveness of treatment. The CT scan can be used to identify both effusions of liquid and gas as well as pleural reactions producing thick membranes of importance for both aetiology and later follow-up. Bronchectasis can be identified on serial sections where the degree of extension can be measured. CT scan is also indicated in patients with emphysema, both for evaluating extension and follow-up. Finally the indications and contraindications for interventional computed tomography, particularly in guiding needle biopsies, is presented.