Plain<unk>  (without contrast) is used to evaluate stone diseases, calcifications within kidneys, density of renal masses and presence of any bleeding before contrast is given. Then iodinated contrast is given intravenously to evaluate kidney tumours (if any) and urinary tract. CT scan is then taken at 30 to 70 seconds (when the contrast reaches the renal cortex and renal medulla) to evaluate the perfusion and vascularity of the kidneys. CT scan taken at 90 to 180 seconds (when the contrast perfused the whole kidney) to evaluate the characterisitics of kidney masses. The contrast starts to drain into the collecting system of the kidneys at 3 minutes after injection and the whole collecting system is well distended with contrast at 8 to 10 minutes. Taking a CT scan at this time is useful to evaluate any strictures or masses from within the ureters or from outside but compressing on the ureters. Contrast<unk>  is also useful to monitor whether a tumour is responding to treatment.
Computed tomography urography
Urinary tract ultrasound
Cystography
Urinary cast
Cystoscopy
Cystometry
Urine cytology
Ureteroscopy