Renal Perfusion Study

Nuclear Medicine at Envision

What is a split function scan?

A renal perfusion study (also called renogram or split function renal scan) examines the blood flow and function of the kidneys using a small amount of a radioactive chemical (called tracers, radiopharmaceuticals or MAG3) that is injected into an arm vein. A gamma camera placed over the kidneys then maps or takes images of the pattern of the tracer passing through the kidneys, giving information useful in diagnosing conditions such as low or uneven function, malformations and obstructions.

What happens during a Renal Perfusion Study?

What to bring

  • A referral from your doctor or medical specialist / and an appointment is required for this examination
  • Any relevant previous imaging
  • Your Medicare card and any concession cards


A referral from your doctor or medical specialist, and an appointment is required for this examination.

If you are pregnant, breastfeeding, or caring for a small child on the appointment day, please notify us in advance to receive special instructions.

Children under the age of 13 may, by prior arrangement arrive early and have a local anaesthetic cream applied to the injection site.

During the hour before the test, drink two or three glasses of water, but avoid excessive amounts of tea or coffee. There is no need to have a full bladder.

During your scan

What to expect during my procedure

When you attend your appointment at Envision Medical Imaging you will be asked to answer a few safety questions, remove any jewellery, watches etc, then change into an examination gown.

The technologist will explain the scanning procedure.  Lasix is injected first, followed by the radioactive tracer, MAG3.  Imaging then follows for 20 minutes. You will then be asked to empty your bladder before a further short scan.

The gamma camera is a large square radiation detector which sits close to the area being examined. You will experience no unusual sensations or discomfort from the scanning process.

Risks and side effects

Renal Perfusion studies are considered very safe with almost no reported adverse reactions attributable to the radiopharmaceuticals used in these examinations.

Renal Perfusion  studies require very small doses of gamma radiation and are only performed where the benefits of the examination are deemed to outweigh any potential risks. At Envision Medical Imaging you can be assured that using the latest technology and with staff trained in radiation reduction techniques, radiation doses are kept as low as reasonably possible.

If you are worried or concerned about having a Renal Perfusion Study, you should discuss this with your referring doctor or medical specialist before coming for your examination.

If you think you may be pregnant, please inform our Nuclear Medicine team before your examination.

Who will perform and report my examination?

At Envision Medical Imaging your examination will be carried out by a Nuclear Medicine Technologist who has a degree in Medical Radiation Science and is accredited by the ANZSNM.

Your images will be reviewed along with your relevant medical history, and any other imaging, and be reported by our Nuclear Medicine credentialed radiologist or Nuclear Medicine physician (a medical doctor specialising in the interpretation of Nuclear Medicine studies).

What happens after a Renal Perfusion Study?

What to expect after my procedure

Radiation from the injected radiopharmaceutical diminishes quickly, however there is still a very small amount of residual radioactivity left for up to 24 hours after your scan.  You are free to resume normal activities following the procedure (unless otherwise advised). If you are caring for a small child, or breastfeeding, we may ask you to take some minor precautions.

How do I receive my results?

If your results are needed urgently, Envision Medical Imaging will arrange to have your results available immediately. Otherwise your referring doctor or health care provider will receive your report within 48 hours of your examination.

Please ensure that you make a follow up appointment with your referring doctor or health care provider to discuss your results.