Overview

A PET-CT scan can show us how the tissues in your body are working, and can help us to identify organs or tissues that are not working normally. For a PET-CT, we inject you with a tracer (usually a weak radioactive form of sugar) and then scan you.

PET-CT is a safe and easy scanning method. PET-CT stands for ‘positron emission tomography with computed tomography’.

Benefits of a PET-CT scan

The tracer we use shows up on the scan to give us more information.

This means we can get important information about many conditions affecting different parts of your body. This will help your specialist to plan the right treatment for you.

Risks of a PET-CT scan

The radioactive tracer that we inject into you only stays in your body for a few hours. This gives you a small amount of radiation. Every request we receive for a PET-CT scan is assessed by a doctor with a specialist training in PET-CT. We’ll make sure that the potential benefits of the test outweigh the very small risks due to the radiation exposure.

The radioactive tracer is complex to make and occasionally it fails on the day of the scan. This means that your appointment might have to be cancelled at very short notice. If this happens, we’ll try to contact you by phone as soon as possible.

There are no significant side effects of this test. Sometimes when doing body or heart scans we need to give patients other medicines and, if this happens, we’ll discuss any possible side effects with you so that you can make an informed decision about your care.

Confirming your appointment

It’s very important that you call us on 020 7188 4988 to confirm your appointment. You must also tell us if you’re taking any prescription medicines, or any you buy from a pharmacy or shop, including any herbal or homeopathic remedies. We might need to give you different instructions about when you should stop eating and drinking (fasting).

This also helps us to make sure we can see as many patients as possible.

Please call us on 020 7188 4988 if:

• you are, or think you might be, pregnant
• you’re breastfeeding, or are the main carer of small children
• you have had any recent issues with having a cannula (very thin plastic tube) inserted into a vein (usually in your arm or hand)
• you’re claustrophobic (do not like tight spaces), have any sensory, physical or learning disabilities, or if you need additional support for your appointment

Bringing someone with you

We encourage people to come to their scan alone. However, if you need a relative, friend or carer, they can come with you, but they’ll be asked to wait outside while you have your scan.

It's very important that you do not bring children or pregnant people to the PET Centre.

Preparing for your PET-CT scan

Please check your appointment information carefully as it contains important information about fasting (not eating) before your scan.

It’s important that you’re not late for your appointment. Each day we get enough tracer for that day’s patients. The tracer’s effects wear off during the day, so scans cannot be delayed.

You should expect to be in the department for 2 to 3 hours. It will depend on the type of scan you have, and will be fully explained to you by our radiographers when you arrive.

What you should wear

You should wear something warm, loose and comfortable as it can sometime be cold in the scanner. We can provide a blanket if you feel cold.

We can provide a hospital gown if you prefer to change when you arrive. If you need help getting changed, please speak to a member of staff.

If you wear glasses or use a hearing aid, please bring these with you.

Jewellery and watches cannot be worn during the PET scan. You will be asked to remove these. Please leave all valuables at home, as we do not have a safe to keep them in.

What you should bring with you

Please bring a list of all your current medicines with you to this appointment.

You may be in the department for up to 3 hours, so you should bring something to keep you occupied. You can read or listen to music before your scan. This is a quiet area, so please bring earphones with you so that you do not disturb other patients.

During your PET-CT scan

A trained radiographer will insert a small needle, called a cannula into a vein in your arm or hand. We then inject the tracer.

If you’re having a brain or body scan, we’ll ask you to relax quietly for 30 to 90 minutes before we take you to the scanner room.

When you have had the tracer injected you will not be able to leave until your scan is completed. This is because of the risk of exposing other people to radiation. If you have to leave because of an emergency, you must speak to a member of staff first.

We’ll ask you to lie on the scanner bed, and will make you as comfortable as we can. You’ll need to keep very still during the scan. It’s important that you do not move, or the pictures could be blurred and the scan may have to be done again.

When you’re in the right position, the scanner bed will move gently, and slide you into the scanner. The PET-CT scanner is shaped like a large tube, with a wide hole in the middle which the bed passes through.

You will usually spend 5 to 30 minutes in the scanner, depending on the type of scan you’re having.

The scan should be completely painless. The most difficult part is keeping still. We’ll try to make sure you’re as comfortable as possible before we start the scan.

Getting your results

We’ll send the results to the specialist who requested the scan, usually within 72 working hours of your scan. If you already have an appointment booked with your specialist, please let us know the date when you come in for your scan.