Radiologic clinics of North America
-
With the increasing use of multidetector CT, small nodules are being detected more often. Although most incidentally discovered nodules are benign, usually the sequelae of pulmonary infection and malignancy, either primary or secondary, remains an important consideration in the differential diagnosis of solitary pulmonary nodules. This article reviews the role of imaging in the detection and characterization of solitary pulmonary nodules. Strategies for evaluating and managing solitary pulmonary nodules are also discussed.
-
Recent technological advances in multidetector computed tomography (CT) have led to the introduction of dual-source CT, which allows acquisition of CT data at the same energy or at 2 distinct tube voltage settings during a single acquisition. The advantage of the former is improvement of temporal resolution, whereas the latter offers new options for CT imaging, allowing tissue characterization and functional analysis with morphologic evaluation. ⋯ The material decomposition achievable opens up new options for recognizing substances poorly characterized by single-energy CT. Although it is too early to draw definitive conclusions on dual-energy CT applications, this article reviews the results already reported with the first generation of dual-source CT systems.
-
Many clinical applications of thoracic computed tomography (CT) require contrast medium to enhance and delineate vascular, mediastinal, hilar, and cardiac structures, and differentiate normal and pathologic vascular or tumoral conditions. Multidetector row computed tomography (MDCT) is superior to single-detector row CT (SDCT) because MDCT permits more efficient and flexible use of intravenous contrast medium to achieve enhancement. However, to fully reap the benefits of MDCT contrast enhancement, the technical challenges associated with optimizing enhancement and scan timing in MDCT need to be solved. This article reviews the basic principles of CT contrast enhancement and discusses common clinical considerations and the protocol design modifications that are necessary to achieve optimal contrast enhancement in thoracic MDCT.