Functional imaging: computed tomography and MRI.

Standard imaging for the lungs allow excellent visualization of normal and abnormal pulmonary patterns. Computed tomography (CT), however, has limitations. The recognized patterns have limited specificity, do not always diagnose the pathology at a treatable stage, and do not provide physiologic information. Advances allow more physiologic approaches in lung imaging, namely, functional imaging. The main functional lung imaging modalities are CT and MRI. Contrast and noncontrast imaging approaches study pulmonary perfusion, dynamics of the flow in the pulmonary artery, and motion. Noble gases allow assessment of regional pulmonary ventilation. We discuss the role of novel imaging techniques in the functional lung assessment.