CT-Urography study protocol: Split-Bolus technique

Abstract

CTU represents the natural technical and instrumental evolution of urography. The multidetector technology, with
the possibility of retro-reconstruction of the images, has allowed the direct representation of the excretory tract with
a significant reduction in acquisition times, decreasing motion artifacts and increasing the definition of the processed
images. Split-Bolus CT dynamic study allows us to obtain, in a single image acquisition, both the nephrographic and
the renal excretory phases; at the same time, we can obtain information of the parenchymal organs in the abdominal
cavity as in the portal/nephrographic phase of a standard CT protocol. The main advantage of Split-Bolus CTU
is undoubtedly the significant saving of the radiation dose administered to the patient, related to the reduction in
the number of phases acquired, with a reported diagnostic efficacy comparable to traditional protocols in terms of
imaging quality. The Split Bolus technique has been used in several clinical contexts, such as in the characterization
of focal liver lesions, in acute pulmonary embolism and in polytrauma patients.