The role of imaging in the investigation of painless hematuria in adults.

The radiologic investigation of asymptomatic hematuria has changed significantly due to the introduction of new imaging modalities and innovative techniques, such as computed tomography urogaphy, which allows a comprehensive evaluation of the entire urinary tract in a single study. There is still a role for "older" imaging modalities, such as intravenous urography and ultrasound, and their use is still advocated in younger patients with a lower risk of malignancy to minimize radiation dose. Combined modality imaging can also be useful for characterization of lesions. Guidelines have recently been published for the radiologic investigation of hematuria; these are discussed in this article.