Imaging Modalities

Abstract

The chapter titled imaging modalities describes various methods of imaging the thorax. Imaging of patients presenting with thoracic complaints typically begins with chest radiography. Ambulatory patients should undergo posteroanterior (PA) and lateral chest radiographs. Anteroposterior (AP) chest radiography should be reserved for debilitated, critically ill and traumatized patients. Special chest radiographic projections such as decubitus chest radiography may be employed for specific indications. Chest CT is the imaging study of choice for evaluating most abnormalities found on radiography. Contrast-enhanced chest CT is optimal for evaluation of vascular abnormalities, the hila and some mediastinal lesions. CT angiography is routinely employed in patients with suspected pulmonary thromboembolism or acute aortic syndromes. High-resolution chest CT is reserved for the evaluation of diffuse infiltrative lung disease and often includes expiratory and prone imaging. FDG PET/CT is increasingly employed in the assessment of patients with malignancy for the purposes of initial staging and post therapy re-staging of affected patients. Ventilation/perfusion scintigraphy is used in the assessment of pulmonary thromboembolism. Additional thoracic imaging techniques include: Fluoroscopy for evaluation of the diaphragm, and ultrasound for evaluation of the thyroid and the pleural space.