Dual-Energy Computed Tomography Characterization of Urinary Calculi: Basic Principles, Applications and Concerns

Dual-energy computed tomography (DECT) is based on obtaining 2 data sets with different peak kilovoltages from the same anatomical region, and material decomposition based on attenuation differences at different energy levels. Several DECT technologies are available such as: the dual-source CT, the fast kilovoltage-switching method, and the sandwich detectors technique. Calculi are detectable using iodine subtraction techniques. DECT also helps characterization of renal stone composition. The advanced postprocessing application enables differentiation of various renal stone types. Calculation of water content using spectral imaging is useful to diagnose urinary obstruction.