Determination of Renal Stone Composition with Dual-Energy Computed Tomography: An Emerging Application

Urinary tract stone disease is common in the Western world. Nonenhanced computed tomography (CT) is the method of choice for stone diagnosis; however, it has a limited role in predicting stone type. Knowledge of stone composition is currently determined by postoperative assessment of stone fragments. A noninvasive tool for accurate characterization of stone composition would improve patient management. Dual-energy CT aids in the differentiation among calcium, uric acid, and cystine stones. In this review we describe the role of dual-energy CT for in vitro and in vivo analysis of urinary stones. We illustrate the technique, review the literature, and discuss future directions.