Background: Staging of bladder cancer, hematuria as well as the evaluation of unclear findings of the kidneys and ureters are the most frequent indications for imaging of the upper urinary tract (UUT). Endourological assessment of the UUT is much more invasive compared to imaging of the bladder, raising the question of the optimal imaging technique. Several technical improvements regarding computed tomography (CT) as well as magnetic resonance imaging (MRI) were implemented in recent years.
Objectives: To compare the efficacy and limitations of the most important imaging techniques regarding the UUT.
Materials and methods: Systematic review of the literature and current German, European, and American guidelines regarding bladder cancer, urothelial carcinoma of the UUT and hematuria.
Results: The CT-based urography has superseded excretory urography and is the first choice for imaging of the UUT. In case of contraindications, MRI is a feasible alternative. In all cases, a urography phase is indispensable.
Conclusions: Imaging of the UUT has to be used in a reasonable combination together with endourological methods and cytology. Optical coherence tomography, confocal laser endomicroscopy and scientific innovations such as radiomics might improve UUT imaging and differential diagnosis of UUT lesions in the future.
Keywords: Excretory urography; Renal pelvis; Ureter; Urography; Urothelial carcinoma.