PET-CT scan patient information
This information tells you about having a PET-CT scan with us (following referral by your doctor) and aims to answer any questions you might have. On this page we aim to provide you with important information about the procedure and answer any questions you may have.
Please read this information carefully and if there are any questions or concerns then contact us on 01923 886311.
Before your scan appointment
Please inform us if the answer to any of the following is yes:
- Are you diabetic?
- Do you feel you need a chaperone?
- Have you had chemotherapy within the past two weeks or radiotherapy within the past four weeks?
- Have you had surgery within the past four weeks?
- Have you had a recent infection or are you feeling unwell?
- Are you pregnant, trying to get pregnant or breastfeeding?
- Have you had previous MRI or CT scans that you have found difficult to tolerate?
- Are you claustrophobic?
- Do you have any additional needs (for example disabilities or mobility issues)?
- Do you need hospital transport? If yes, this is something the team who referred you for your scan can help you with.
- Do you need an interpreter?
- Do you have any other appointments booked on the same day as this scan?
- Do you weigh over 130 kg or 20 stone?
Unfortunately we’re unable to give sedatives or painkillers. If you do need something to calm your nerves or reduce pain, please speak to your doctor in advance and follow their advice closely. If you’ve taken a sedative, you must bring someone with you to your appointment.
Preparing for your scan
- Drink at least two or three glasses of plain water in the four hours before your appointment. You may want to bring a bottle of water with you.
- Do not exercise for 24 hours prior to your scan (for example, running, cycling, horse-riding, gym exercise but also holding a baby or knitting). You need to be as relaxed and rested as possible.
- Please continue to take medications as usual unless otherwise instructed. If you have to take any medications with food, ask your doctor for further advice.
- Please don’t bring children with you.
IMPORTANT: If you’re having an FDG PET-CT body or brain scan, don’t eat for 6 hours before your scan (this includes chewing gum, sweets or cough drops), and don’t drink anything other than plain water during this period.
If you’re having a choline PET-CT scan or PSMA PET-CT scan, you can eat as normal and don’t have to stick to plain water. Your appointment letter tells you what kind of scan you’re having.
What is a PET-CT scan?
A PET-CT scan is a combination of two types of scanning technique in which a small amount of radioactive tracer (a type of fluid) is injected into a vein. This provides information about the anatomy (CT) and function (PET) of your internal organs. The scan tells doctors about the presence, location and severity of cancers. It can also be used for other conditions such as infection or inflammation and conditions that affect the brain. We are able to provide important information to help your doctor plan an appropriate treatment for you.
The PET-CT scanner is a large, quiet machine with a ring-like structure. You will need to be able to lie on your back on the scanning couch (see picture), which will move into the ring.
On the day
If you are having your scan at Mount Vernon
Please bring a dressing gown or warm, loose, metal-free clothing. You can take your usual medicines unless otherwise instructed. If in doubt, please contact us, especially if you are diabetic.
Avoid bringing valuables along to your appointment, as we don’t have secure space to store them for you.
Please arrive at the Paul Strickland Scanner Centre reception at Mount Vernon Hospital on time for your appointment because the radioactive tracer that we inject is ordered specifically for you and only works for a short time. If you are late we may not be able to proceed with your scan. If you are unable to attend or are going to be delayed, please telephone us at the earliest opportunity on 01923 886311.
Sometimes, due to the complexity of both the scanner and the radioactive tracer that is injected, we can experience unforeseen technical difficulties which could mean we’re unable to scan you on the day. If this happens, we may need to cancel your appointment at short notice but we will rebook you for the first available convenient date.
If you’re having a scan of your brain, your injection and scan will take place in a darkened room.
If you are having your scan at Lister Hospital Stevenage
If you are having your scan at the Lister Hospital in Stevenage, it will take place in a mobile PET-CT unit. You need to report directly to the mobile PET-CT unit on the Plaza.
Please dress in warm, loose, metal-free clothing. You can take your usual medicines unless otherwise instructed. If in doubt, please contact us, especially if you are diabetic.
Please arrive on time for your appointment because the radioactive tracer that we inject is ordered specifically for you and only works for a short time. If you are late we may not be able to proceed with your scan. If you are unable to attend or are going to be delayed, please telephone us at the earliest opportunity on 01923 886311.
Sometimes, due to the complexity of both the scanner and the radioactive tracer that is injected, we can experience unforeseen technical difficulties which could mean we’re unable to scan you on the day. If this happens, we may need to cancel your appointment at short notice but we will re-book you for the first available convenient date.
The radioactive tracer has no documented side effects. The scan involves exposure to radiation in the form of gamma and X-rays. We ensure that the radiation dose you receive is both appropriate to address the clinical question being asked, and is as low as is achievable. A typical PET-CT scan radiation dose is equivalent to around 5 years of average background radiation which we all receive in the UK. The radiation dose for a PSMA PET-CT scan is typically about one quarter lower than that of other types of PET-CT scan.
The doctor who has referred you to us has judged that the risk of the radiation dose is outweighed by the potential benefits of the scan.
One of our PET-CT specialists will analyse your scan. We will then send your report back to the doctor who referred you for your scan.
If you do not have another outpatient appointment arranged and you do not hear anything about the results within 3 weeks, we suggest that you telephone the referring doctor’s secretary for advice.
Having your PET-CT scan
A member of staff will accompany you to a private room, ask you about your medical history and explain what will happen.
- We will give you an injection of the radioactive tracer
- We will ask you to relax in a resting bay for about an hour to allow the injection to be absorbed by your body.
- Immediately before your scan, we will ask you to remove any metal items and empty your bladder.
- We will then take you into the scanner room and ask you to lie on your back on the scanning bed.
- The scan will usually take between 20 and 60 minutes. When the scan starts, the bed will move slowly through the scanner.
- The radiographer or technologist will operate the scanner from the next room, where you can be assured that they can see and hear you at all times via a connecting window and intercom. The scanner is not noisy and having a scan is not painful.
Important information about your PET-CT scan
Sometimes, due to the complexity of both the scanner and the chemical tracer that is injected, we can experience unforeseen technical difficulties which could mean we’re unable to scan you on the day. If this happens, we may need to cancel your appointment at short notice but we will rebook you for the first available convenient date.
Bringing a friend, relative or carer?
After the scan
Due to infection control measures, we discourage our patients from bringing friends and family along to appointments. One person will be allowed to accompany you if you require support with translation, physical disability, a mental health issue, learning disability, autism or dementia.
Please do not bring children or pregnant friends/relatives with you or we may be unable to scan you.
If awaiting transport to collect you, please feel free to bring something along to eat and drink.
- Once the scan is complete you are free to leave as soon as you feel ready. Keep at least one arm’s length away from others.
- Avoid pregnant women and young children.
- You may eat and drink as you normally would. Drink plenty of fluids and empty your bladder frequently.
PSMA PET-CT scans
A Prostate Specific Membrane Antigen (PSMA) PET-CT scan specifically tests for Prostate Specific Membrane Antigen (PSMA), a type of protein that prostate cancer cells have more of. A PSMA scan may be able to detect prostate cancer earlier than other scans, which could benefit your treatment.
Everything you read on this page applies to a PSMA PET-CT scan too, however the radiation dose for a PSMA PET-CT scan is typically about one quarter lower than that of other types of PET-CT scan.
Last updated 13 November 2023. Next clinical review due March 2024.
Information for patients having their scan in Northwood
Your scan will take place at Mount Vernon Hospital in Northwood. The address is Mount Vernon Hospital, Northwood.
See detailed travel information and map
- Information for patients having their scan at Lister Hospital, Stevenage
Your scan will take place in a mobile PET-CT scanner at the Lister Hospital in Stevenage. The mobile PET-CT scanner is a big white lorry with “InHealth PET CT” written on it and it is parked just south of the Plaza. There is a map on the back page of this booklet.
The address for the Lister Hospital is Coreys Mill Lane, SG1 4AB, Stevenage, Hertfordshire.
If you get lost, go to the main Lister Hospital reception on level 3 and ask them to ring the mobile unit so you can be collected.
- How to get there by bus
Busses stop at the south side of the hospital on Coreys Mill Lane. From the bus stop, follow the outdoor footpath in the direction of the main hospital entrance until you get to just south of the Plaza where the mobile scanner unit is parked. For information on which bus is right for you, ring the Hertfordshire County Council travel line on 0300 123 4050 or visit www.intalink.org.uk
- Get there by rail
Trains stop at Stevenage Railway Station, with regular busses running between Stevenage town centre and the hospital.
If you are getting a lift by car
Ask to be dropped off in the drop off area before the multi-storey car park near the mobile PET-CT unit.
- Parking arrangements
The Lister Hospital in Stevenage has a large multi-storey car park which also has spaces for blue badge holders. You will receive a chip coin token when you enter the car park and will pay on exit for the time stayed. Pay machines are available in the lobby of the car park. Make sure you retain your chip coin once you’ve paid, as you’ll need it to exit the car park. Upon exiting the car park, follow the outdoor footpath to just south of the Plaza and look out for the scanner lorry.
- Changes to travel and parking information
We have no control over parking and travel arrangements outlined in this booklet and they can change at any time without notice. Parking arrangements can be verified with the Lister Hospital on 01438 314333. For public transport information, ring 0300 123 4050 or visit www.intalink.org.uk
You will be welcomed at our reception desk by one of our Radiographic Assistants (RAs). Your scan will be performed by one of our Radiographers, who may be assisted by an RA. Female RAS wear either a plain white tunic or a plain white tunic with light blue trim, while female radiographers wear a white tunic with black trim. Their male counterparts wear a plain white shirt. Both male and female uniformed staff wear black trousers.
We aim to provide our patients with world-class scanning facilities, clinical excellence and opportunities to take part in innovative health research studies.
We welcome your feedback. Please complete one of our comments cards during your visit, or email email@example.com. This helps us improve our service.
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