Nuclear medicine

  • Nuclear medicine is a medical imaging specialty that involves the use of radiopharmaceuticals (also known as radioactive medicines or tracer medicines) for diagnostic imaging (scans), therapy and research. Nuclear medicine imaging combines the use of tracer medicines and gamma cameras (cameras that can detect the gamma radiation that the tracer medicine emits), to provide images that can see inside the body. While nuclear medicine scans involve radiation exposure (like with X-rays and CT-scans), the exposure is limited as much as possible. 

    Why does my child need a nuclear medicine scan?

    Nuclear medicine scans are performed for many different reasons, including: 

    • to see how different organs in the body are functioning 
    • to look at the shape or structure of parts of the body 
    • for early detection, treatment, and management of diseases. 

    Nuclear medicine scans can be performed on most organs of the body, and are commonly used to examine the kidneys, gastrointestinal tract (digestive system) and brain. They can also be used to examine bones.

    Nuclear Medicine studies routinely performed at RCH include: 

    • Bone scan
    • Mag3 renal scan
    • DMSA renal scan
    • Gastric emptying and gastro-intestinal transit studies
    • Thyroid scan and therapy
    • Brain perfusion (epilepsy)
    • GFR renal studies
    • MIBG whole body imaging

    Preparing your child for their appointment

    For some ideas on how to prepare your child for the procedure, and tips on distracting them and helping them stay calm during the procedure, see our fact sheet Reducing your child's discomfort during procedures.

    It may be helpful to your child if the procedure is explained to them before they come in for their important. Explain that: 

    • the scans do not take long
    • the scans are painless
    • a parent or carer can stay with the child during the scan.

    Most children can watch a movie while having their scans, and you are welcome to bring in a smartphone, tablet, or your child's favourite movie or TV show to keep your child occupied and distracted during the scan. 

    Specialist staff from Child Life Therapy may also be of benefit for your child. The Child Life Therapist engages families in imaging-specific education and medical play, as well as providing distraction and support during procedures. Appointments for Child Life Therapist support can be made in advance via Medical Imaging or your referring doctor.

    What to expect with a nuclear medicine scan

    Before the procedure

    Preparation for a nuclear medicine examination depends on the type of scan your child is having, and your child’s individual needs. Some scans require fasting for the actual imaging sequences, and others require fasting for sedation – please confirm with your individual instructions at the time of booking. Distraction techniques are utilised for all scans for all age patients in nuclear medicine.

    If your child requires an injection, topical anaesthesia will be applied to the injection site to make it numb – this can be in the form of a cream or via Coolsense® – a hand-held device that uses cryotherapy to numb the area. Cream usually takes over 45 minutes to work, so you will be asked to attend the department earlier than your scheduled appointment time. You will be advised if you need to do this when you are given your appointment.   

    Whether or not your child needs sedation depends on the type of scan they are having and their individual circumstances. In cases where a child is unable to remain still enough or they are very anxious or distressed, sedation may be required. Your child will be assessed to ensure sedation is suitable for them. Typical studies that may require sedation include bone scans, MIBG whole body scans and brain scans, and this is usually required for younger children.

    See our fact sheet Sedation for procedures.

    During the procedure

    You and your child will be invited into the camera room by a technologist and the procedure will be explained. Your child will then be positioned on the scanning bed. Seat belts may be placed around your child to help them remain still, as well as for safety purposes as the scanning bed is quite narrow and can move.  

    Your child will be administered the tracer medicine, which is given by: 

    • intravenous (IV) needle (the most common method) 
    • oral drink 
    • oral tablet

    The imaging can take place after the tracer has been administered. It may involve the camera moving slowly over or around your child's whole body, or a specific area of their body. Your child is required to keep quite still whilst the camera is taking images.  

    The average time for a nuclear medicine examination is 30–45 minutes, but there may be multiple scans or sequences required over a longer period of time. 

    After the scan 

    Usually you will be able to leave straight after the completion of the scan sequences, unless your child has had sedation. If your child had sedation, they will be required to remain under the care of the department nurse until they have recovered appropriately.  

    A report will be prepared by the Nuclear Medicine Specialist and sent to the referring doctor. The report is usually available within a few days but can be received earlier if required. If you have any questions about why your child needs a nuclear medicine scan, or questions about the results of your scan, please speak to your doctor.

    Nuclear medicine scan with general anaesthetic 

    Some nuclear medicine scans need to be performed while your child is asleep under a general anaesthetic. This is quite rare, but may be required if sedation will not be effective for your child and their scan. If your child does need a general anaesthetic for their scan, you will be given specific instructions for what to do before the scan, including fasting requirements.  

    Key points to remember 

    • Nuclear medicine scans use tracer medicines and gamma cameras to provide images of organs and bones inside the body
    • Some scans require fasting for the actual imaging sequences, and others require fasting for sedation
    • Your child will be lying on a scanning bed and has to keep very still during the procedure
    • Sedation may be required for children who are unable to remain still enough, or who are very scared. This is more common for scans whole body scans in younger children
    • The scans are painless, and if an injection is required your child can have numbing solution applied to the injection site

    For more information

    Common questions our doctors are asked

    How safe is the tracer medicine my child will be given? 

    It is extremely rare to have a reaction to any of the tracers used in nuclear medicine. Specialised staff or on hand to provide help should any symptoms arise, however unlikely. Once the scan is complete, your child will pass the tracer (through urine or faeces) over the following hours or days without any concern. 

    My child is anxious about medical procedures and I am not sure they will be still enough for the scan. How can I help?

    To get some ideas of how to talk to your child about the scan before you come to hospital, see our fact sheet. Also consider showing your child our ‘Be Positive’ videos of children having procedures at The Royal Children's Hospital (RCH). Seeing the videos may help them by knowing what to expect. You can also download our Okee in Medical Imaging app, which includes games and information especially designed to help children feel more comfortable about having medical imaging at RCH.

    Specialist staff from Child Life Therapy may also be of benefit for your child. The Child Life Therapist engages families in imaging-specific education and medical play, as well as providing distraction and support during procedures. Appointments for Child Life Therapist support can be made in advance via Medical Imaging or your referring doctor.

    Are there radiation risks with this examination?

    All medical imaging procedures at RCH have been justified by a Radiologist or Specialist before the exam is performed. All imaging procedures are optimised – each study is performed with the aim to provide the highest quality imaging with the lowest radiation dose to each child.

    For more information on radiation, please see the Australian Government fact sheet: Ionising Radiation and Health, or speak to your technologist.

    Developed by The Royal Children's Hospital Nuclear Medicine department. We acknowledge the input of RCH consumers and carers.

    Reviewed November 2018.

    This information is awaiting routine review. Please always seek the most recent advice from a registered and practising clinician.

    Kids Health Info is supported by The Royal Children’s Hospital Foundation. To donate, visit


This information is intended to support, not replace, discussion with your doctor or healthcare professionals. The authors of these consumer health information handouts have made a considerable effort to ensure the information is accurate, up to date and easy to understand. The Royal Children's Hospital Melbourne accepts no responsibility for any inaccuracies, information perceived as misleading, or the success of any treatment regimen detailed in these handouts. Information contained in the handouts is updated regularly and therefore you should always check you are referring to the most recent version of the handout. The onus is on you, the user, to ensure that you have downloaded the most up-to-date version of a consumer health information handout.