More invasive tests—such as cystoscopy, ureteroscopy, and nephroscopy—allow clinicians to make diagnoses under direct vision and simultaneously perform therapeutic interventions. These tests, however, do not provide any functional information.

Acute decompression of the urinary tract may be accomplished using transient interventions, such as placement of a Foley catheter, suprapubic tube, ureteral stent, or percutaneous nephrostomy tube. Depending on the level and cause of obstruction, definitive therapy may require surgical intervention, such as a transurethral outlet surgery (e.g., urethrotomy, prostate incision or resection), ureteral surgery (e.g., incision, balloon dilation, ureteroscopy), or abdominal surgery (e.g., ureteropelvic junction obstruction repair, removal of retroperitoneal tumor).