Enhancing Image Quality in the Era of Radiation Dose Reduction: Postprocessing Techniques for Body CT
Authors: Pamela T. Johnson, MD and Elliot K. Fishman, MD
The pillars of excellence in body CT are guided by traditional goals of quality (protocol optimization and interpretative accuracy) and safety (radiation modulation and avoiding contrast-induced nephropathy). As medicine transitions to high-value practice, excellence has evolved into providing the most diagnostically accurate information possible from each CT examination while protecting patients from unnecessary scans, radiation, and costs. Body CT is a leading source of patient radiation exposure in medical imaging [1, 2], and the Image Wisely Campaign encourages all radiology professionals to safeguard patients by pledging to optimize radiation use [3. In body CT, radiation dose is tempered by limiting the number of phases performed during each CT and modulating tube current and peak kilovoltage [4, 5]. The ACR recently released their second slate of Choosing Wisely recommendations, which advises radiologists to avoid abdominal CT protocols with noncontrast and delayed phases unless the additional acquisitions provide an incremental increase in valuable diagnostic information [6.
Reduction of CT dose can compromise image quality and confound diagnosis by increasing noise, which has been addressed by manufacturers developing iterative reconstruction. Radiologists may not be aware of additional resources available at the scanner and the workstation to increase lesion conspicuity and detection as image quality and quantity decrease, including virtual noncontrast data sets from dual-energy CT, 3-D rendering (maximum intensity projection [MIP], volume rendering [VR], and cinematic rendering [CR]), computer-assisted diagnosis, and texture analysis. [Read more….]