[Painless hematuria: diagnostic workup using multislice computertomography].

BACKGROUND: Multislice computed tomography (MSCT) is the current standard in the work-up of hematuria. The examination protocol should be as accurate as possible while avoiding unnecessary exposure to ionizing radiation.
OBJECTIVE: To present opportunities to reduce the overall radiation dose by tailoring examination protocols to the clinical requirements.
METHODS: A four-phase MSCT protocol is an accurate tool to diagnose the cause of unclear hematuria in the majority of cases. In patients younger than 30 years and in patients younger than 40 years presenting only with microhematuria, the use a noncontrast low-dose scan is adequate. In addition, patients younger than 50 years may not require precontrast and a late-phase CT scans. Another opportunity to omit acquisitions is a combination of different phases by using the so-called split bolus injection protocol, where the administration of contrast is performed 10 min before the scan and the portal-venous phase and the late phase are combined. If dual energy is available, the precontrast scan can be calculated from the enhanced series. For the evaluation of a renal cyst, a two-phase CT protocol is sufficient to obtain diagnostic information.