Urinary Tract and Bladder

As has already been stated in describing the chemical and physical properties of the sulfur hexafluoride microbubble [1, 2], it has no excretion through the emunctory kidney. Though this means the advantage that it can be used in patients with reduced renal functionality, from the diagnostic point of view it presents a limit in the detection of urothelial lesions in the calicopyelic and ureteral regions. In fact, the presence of new urothelial formations within the kidney may be suspect when accompanied by hydronephrosis or when a mass is detected with infiltrative growth into the parenchyma: compared to the baseline sonogram, CEUS can more accurately identify the presence of a lesion with heterogeneous and variable post-contrast enhancement (Fig. 3.1), when combined with calyceal dilatation or of the renal pelvis (Fig. 3.2); but it does not provide a reliable determination if it belongs to the urinary excretory system. For this reason, the uroCT (urographic CT) or the uroMRI (urographic MRI) turn out to be the methods of choice (Fig. 3.3).