Modality	Advantages and disadvantages
Intravenous urography	Considered by many to be best initial study for evaluation of urinary tract
	Widely available and most cost-efficient in most centers
	Limited sensitivity in detecting small renal masses
	Cannot distinguish solid from cystic masses; therefore, further lesion characterization by ultrasonography, computed tomography or magnetic resonance imaging is necessary
	Better than ultrasonography for detection of transitional cell carcinoma in kidney or ureter
Ultrasonography	Excellent for detection and characterization of renal cysts
	Limitations in detection of small solid lesions (< 3 cm)
Computed tomography	Preferred modality for detection and characterization of solid renal masses
	Detection rate for renal masses comparable to that of magnetic resonance imaging, but more widely available and less expensive
	Best modality for evaluation of urinary stones, renal and perirenal infections, and associated complications
	Sensitivity of 94% to 98% for detection of renal stones, compared with 52% to 59% for intravenous urography and 19% for ultrasonography