DTPA scan is functional imaging of kidneys and urine transit. It provides detailed information about kidney function and drainage. The DTPA is the name of the compound used in this test and is an acronym of Diethylene Triamine Penta Acetic Acid and labelled with 99mTechnitium radioisotope to form 99mTc-DTPA. The other terms used for this scan are "Renal Dynamic Scan (RDS)" or "Dynamic Renography". Some physicians also refer to it as "DTPA with GFR". GFR is an acronym for "Glomerular Filtration Rate" and is inherently estimated during this test. There are many indications for this test, including measuring the relative function of a possibly obstructed kidneys, looking for possible compromised renal function, establishing a baseline for any future loss of function, and determining whether renal obstruction is present in an asymptomatic patient for whom hydronephrosis was detected on prior imaging.