Imaging modalities in obstructive uropathy
What other imaging modalities are helpful in the evaluation of obstructive uropathy?
A computed tomography (CT) scan can provide a more detailed evaluation of hydronephrosis, hydroureter, and/or bladder distension from outlet obstruction.
The noncontrast phase of a CT scan is best for identifying obstruction from stones.
If kidney function permits the use of contrast, a delayed contrast phase can show contrast draining from the kidneys to the bladder and identify the cause and location of intrinsic (inside the ureter) and extrinsic (compression of ureter from the outside) forms of ureteral obstruction.
A MAG-3 (mercaptoacetyltriglycine) nuclear medicine renal scan can evaluate differential kidney function (kidney uptake) and can quantify drainage times for each kidney unit after administration of a diuretic.
