Information for patients
This leaflet can be made available in other formats including large print, CD and Braille and in languages other than English, upon request.
The purpose of this leaflet is to explain the potential risks from the small amounts of radiation to which you will be exposed for your chest X-ray and lung scan.
It does not apply to other kinds of imaging such as ultrasound and MRI imaging.
Why am I having a lung scan?
Your healthcare team are concerned that you could have a blood clot in your lungs that may reduce your ability to breathe properly. This is a serious condition that poses a risk to your health and wellbeing.
The lung scan will help confirm or rule out their suspicions which will affect the decision to recommend medication. Treatment with medication is itself not without a small amount of risk.
The healthcare professionals involved always check that the benefit of having the test is greater than the risk from the small amount of radiation.
You will need to have a chest X-ray and then a nuclear medicine lung scan.
The nuclear medicine scan uses a small amount of radioactive substance to see where blood flows in your lungs and a
radioactive gas to see where the air flows in your lungs. The radioactive substances may stay in your body for a short period of time.
We will explain what the scan entails before we give you the radioactive substance.
Are there any risks in using radiation?
We are all exposed to background radiation every day. Any amount of radiation has potential ill health effects (very small increased chance of cancer); however, the amount used in these tests is minimal.
The amount of radiation you will be exposed to as part of this lung scan is about the same as you would naturally receive in 1-2 years.
The lung scan and X-ray may increase radiation risks by a very small amount, less than 1 in every 6000.
|Equivalent background radiation
|Increased radiation risk
|Less than 1 week
|Less than 1 in 100,000
|Nuclear medicine lung scan (ventilation and perfusion)
|1 to 2 years
|Less than 1 in 6,000
What are the effects on my baby?
Very young children are slightly more at risk to radiation than adults. If possible, to reduce the risk to your baby we ask that you avoid carrying the baby for long periods of time until the morning after the test.
A small amount of the radioactive substance is also expressed in your breast milk. If you are breast feeding and are producing mature milk, we need to you stop directly feeding your baby for 20 hours
after the scan.
The baby can be fed any spare milk you can bank before the scan or a suitable formula alternative. During the 20-hour period, please express the breast milk you produce. This can be frozen for use 3 days after the lung scan. Direct breast feeding can resume 20 hours after the scan.
If you are breast feeding but your milk has not fully started, we will do a personal assessment of what to do after the scan and advise you appropriately.
What if I don’t have the test?
The greatest risk is an untreated blood clot. If you do not have the scan, your care team will likely recommend continued use of anticoagulants.
Without the lung scan, we will not know if these anticoagulants are unnecessary.
The very small dose of radiation in the lung scan is a much smaller risk than the unnecessary use of anticoagulants.
You should discuss any concerns with your healthcare team.
What if I have more questions?
Please talk to your doctor or any of the team carrying out your nuclear medicine test if you would like to discuss any of this further.
Further risk comparisons can be found at GOV.UK Guidance on Ionising radiation: dose comparisons.
Information produced by:
Northern Medical Physics & Clinical Engineering,
North Tees and Hartlepool NHS Foundation Trust
Notes for guidance on the clinical administration of radiopharmaceuticals and use of sealed radioactive sources, Administration of Radioactive Substances Advisory Committee (2023).
Radiation Risks from Medical X-ray Examinations as a Function of the Age and Sex of the Patient (HPA-CRCE-028), Health Protection Agency (2011).
Ionising Radiation Exposure of the UK Population: 2010 Review (PHE-CRCE-0.26), Public Health England (2010)
Comments, concerns, compliments or complaints
Patient Experience Team (PET)
We are continually trying to improve the services we provide. We want to know what we’re doing well or if there’s anything which we can improve, that’s why the Patient Experience Team (PET) is here to help. Our Patient Experience Team is here to try to resolve your concerns as quickly as possible. The office is based on the ground floor at the University Hospital of North Tees if you wish to discuss concerns in person. If you would like to contact or request a copy of our PET leaflet, please contact:
Telephone: 01642 624719
Freephone: 0800 092 0084
Opening hours: Monday to Friday, 9:30am to 4:00pm
Email: [email protected]
Out of hours
Out of hours if you wish to speak to a senior member of Trust staff, please contact the hospital switchboard who will bleep the appropriate person.
Telephone: 01642 617617
Data protection and use of patient information
The Trust has developed Data Protection policies in accordance with Data Protection Legislation (UK General Data Protection Regulations and Data Protection Act 2018) and the Freedom of Information Act 2000. All of our staff respect these policies and confidentiality is adhered to at all times. If you require further information on how we process your information please see our Privacy Notices.
Telephone: 01642 383551
Email: [email protected]Privacy Notices
This leaflet has been produced in partnership with patients and carers. All patient leaflets are regularly reviewed, and any suggestions you have as to how it may be improved are extremely valuable. Please write to the Clinical Governance team, North Tees and Hartlepool NHS Foundation Trust, University Hospital of North Tees, TS19 8PE or:
Email: [email protected]
Leaflet reference: PIL1432
Date for Review: August 2026