An intravenous pyelogram, also called intravenous urography, is a diagnostic X-ray of the kidneys, ureters, and bladder. When a contrast dye is injected intravenously (IV), the urinary tract will show up very clearly, which is not seen on regular X-rays. An intravenous pyelogram may be done for many reasons, including the following:
- To detect kidney tumors
- To identify blockages or obstructions of the normal flow of urine
- To detect kidney or bladder stones
- To establish if the prostate gland is enlarged
- To detect injuries to the urinary tract
As the contrast dye moves into and through the kidneys, ureters, and bladder, X-rays taken at short intervals can capture its movement. A delay in the contrast dye moving through the urinary system may indicate an obstruction (blockage) in the kidney's blood flow or poor kidney function.
A radiologist can then assess the function and detect abnormalities of the urinary system. This test is usually ordered as one of the first tests in cases of suspected kidney disease or urinary tract disorders.
Prior to an intravenous pyelogram, Northwell Health recommends the following:
- Patients should have nothing to eat or drink four hours prior to the exam.
- Premedication regimen for iodinated contrast (iodine dye): Patients should notify the office where they will have the exam if they have had prior contrast reactions. If intravenous contrast is still deemed necessary a patient will require a prescription from a physician for the following:
- Prednisone: 50 mg by mouth 13 hours prior to scan; 50 mg by mouth seven hours prior to scan; 50mg by mouth one hour prior to scan;
- Benadryl: 50 mg by mouth one hour prior to scan.
Note: Patients will not be able to drive or return to work for 12 hours following the exam.