Purpose: This study assessed means by which to optimise 64-slice computed tomography urography (CTU) in evaluating the urinary tract, with a view to obtaining the best trade-off between image quality and radiation dose.
Materials and methods: Image quality was analysed in terms of spatial and contrast resolution on several scans of a phantom performed with automatic dose modulation and different reconstruction kernels and accepted noise level. Data were compared with the radiation dose values recorded for 52 patients who underwent CTU examination.
Results: Radiation dose and image quality differed considerably depending on the reconstruction parameters, even though a higher dose did not always imply better image definition. Data obtained in the phantom were consistent with those obtained in patients. Depending on the clinical problem, the radiation dose varied from 6.2 to 17.6 mSv.
Conclusions: CTU cannot be considered a standard examination: the scan parameters need to be adapted to the image quality required for the specific clinical problem.