Recent advances in pulmonary imaging

Recent years have witnessed an explosion in imaging technology applicable t o chest medicine. These include CT and magnetic resonance angiography (MRA) for the diagnosis of pulmonary embolism, and high-resolution CT for the de tection and characterization of diffuse lung diseases and the quantificatio n of emphysema. Newly developed approaches to pulmonary functional imaging using CT and MRI have been applied to the evaluation of pulmonary ventilati on and perfusion and to the detection of small airways disease. Volumetric CT imaging techniques together with advanced image processing have made pos sible "virtual bronchoscopy." Positron emission tomography provides an impo rtant new approach to the accurate detection and staging of chest malignanc ies and to the evaluation of pulmonary nodules. Finally, new digital imagin g techniques, which are rapidly replacing conventional x-ray film, offer th e possibility of computer-aided diagnosis.