GFR Kidney Function Test

Information for patients 

Nuclear medicine is the use of small amounts of radioactive materials to gain images for diagnosis or treatment of various conditions or diseases. Images are created by administering a radioactive compound (“tracer”) which targets a particular region of interest. All tests are safe and non-invasive.

Unlike other scanning methods such as: X-rays, nuclear medicine test provides information about physiology and function.

Your doctor has requested a GFR Kidney function Test for you and in this leaflet we describe what is involved.

Please read through everything very carefully.

What is this study going to show?

The purpose of this study is to obtain an indication of kidney function. This will help your doctor diagnose your condition and give you appropriate treatment.

Please allow approximately five hours for the study.

Is the radioactivity harmful?

Your test will involve the use of a small amount of ionising radiation (similar to a CT scan) and the risk associated with this is low. 

The main benefit of the test is making the correct diagnosis, so you can get the treatment that is right for you.  This benefit is far greater than the small risk of radiation.

Preparing for the study

No preparation is required. You may eat and drink as normal.

Special Instruction

You will need to inform us if you have had any nuclear medicine examination in the last 6 months or have had a CT scan in the last week.

What does the study involve?

Radioactive Tracer Injection

At the beginning of the study we will inject a small amount of radioactive tracer into a vein in your arm.

Waiting Period

During the waiting period between the injection and scan, you may eat normally and leave the department while waiting.

Blood Samples

You will be given a time to return for your blood samples by the technologist administering your injection. This will be approximately 2, 3 and 4 hours later.

How long does the test take?

Your stay with us will be in between 5 hours. You will have time in between to leave the department if you wish to.

Further information

Please do not hesitate to ask a member of staff in the department if you have any questions.

Alternatively, you can contact the booking office on 020 3315 8415

If you are currently on any medication please continue having them. If possible please bring you list of medications with you.

Can I bring a friend with me?

Yes, although some parts of your test may require your friend to sit outside the examination room. Please do NOT bring children or pregnant women (unless the test is for the child).   

What measures I have to take?

We advise patients to drink plenty of fluids to flush the remaining radioactivity out of the body. You may then resume a normal diet unless advised otherwise.

What happens to the study results?

A report will be sent to your consultant doctor within two weeks. Unfortunately you will not receive results on the day of your test.

What if I am pregnant or breastfeeding?

If you believe that you may be pregnant or if you are breastfeeding it is important that you contact the department as soon as possible before your test, as it may need to be rescheduled.

Contact information

Chelsea and Westminster Hospital

Nuclear Medicine Department
1st Floor, Lift Bank D (within main X-Ray department)
T: 020 3315 8415