Renal Scan

A Nuclear Medicine Renal Scan (also known as a ‘MAG3 Renal Scan’) is performed to look at your kidneys’ blood supply, function and the excretion of urine. The test analyses how each kidney contributes to overall kidney function and can be used to uncover high blood pressure, a narrowing of arteries, and any blockage or interruptions.


  • Patients should wear loose comfortable clothes (no zippers, buttons, jewellery or metallic accessories).
  • Patients should arrive 10-15 minutes early to complete paperwork
  • If the Renal Scan is being done to evaluate renal hypertension or renal artery stenosis, some blood pressure medications should be stopped 4 – 7 days prior to the examination.
  • Patients should discuss medications and preparation with their doctor and Lakes Radiology at the time of booking the scan.
  • Patients must bring their request/referral form on the day (or check that their request/referral is at the practice)
  • Notify Lakes Radiology team of any allergies, existing medications and if there is a chance you could be pregnant
  • Patients should inform the receptionist when booking the procedure if you are breast feeding as alternate arrangements may need to be made (ie you may need to stop breast feeding for a short time).


  • There are minimal risks in having renal scans.
  • The gamma ray camera will be held close to the patient’s kidneys.
  • The patient should remain very still whilst the technician is taking images.
  • After 15 – 20 minutes of scanning the patient may be given a diuretic injection through the same cannula. This injection causes the kidneys to work harder and make more urine.
  • At the end of the initial scan the patient may be asked to go to the toilet and empty their bladder, then return for a further imaging.
  • The images will be checked by the radiologist to ensure quality diagnostic images have been taken.
  • The patient should contact their referring doctor for the result.

Risks or Side Effects

  • Exposure to radiation is similar to that received during a routine diagnostic x-ray.
  • There is a risk of allergic reaction to the radiopharmaceutical or diuretic however these are rare and usually minor.
  • The patient should advise Lakes Radiology if they have had a previous allergic reaction to medication prior to the administration of the radiopharmaceutical injection.
  • If a dose of a diuretic is given, the patient may feel thirsty and will need to drink plenty of fluids for the rest of the day to ensure hydration is maintained. The patient may need to visit the toilet more often to empty the bladder.

Privacy Statement | eReferrals | Image Access (Doctors only)