What are lung perfusion and ventilation scans?
A lung perfusion scan is a test to see how blood flows to the lungs.
A lung ventilation scan is a test to see how well air and blood flow through all areas of the lungs.
These scans are normally done for patients with chest and breathing problems.
How are the scans done?
Some children only have a lung perfusion scan, but others have scans for lung perfusion and ventilation. Each scan is done by a nuclear medicine technologist.
If your child is having both scans, the ventilation scan happens first.
Lung ventilation scan
For this scan, your child will be given a mask or mouthpiece and asked to breathe in and out a tiny amount of radioactive mist for about five minutes.
The technologist will then remove the mask or mouthpiece and use a special camera to take pictures of your child's lungs.
Lung perfusion scan
Your child will first be given a small needle (injection) into a vein in their arm or the back of their hand. The injection contains a very small amount of radioactive medicine that mixes with the blood and will go to the lungs.
Your child will then lie down on a narrow table with a safety belt across their stomach to keep them safely in place while a special camera takes pictures of their lungs. In most cases they can watch a movie as the scan is being done.
Note: The injection before the lung perfusion scan is not painful, but your child's hand or arm can still be numbed first with a topical anaesthetic (a special cream or cooling spray). If you would like this option, it is best to arrive at least 30 minutes before your appointment to allow the anaesthetic to take effect.
Does my child need to do anything special to prepare for the scan?
No, your child can eat and drink as usual.
How long does the scan take?
The lung perfusion scan on its own takes 15 to 20 minutes. The two scans take 45 to 60 minutes in total.
Will I be able to stay with my child during the scan?
One parent or guardian may stay in the room during the scan, but no other children are allowed.
Does the scan carry any risks?
A lung perfusion and ventilation scan involves giving a very small amount of radiation to your child. The nuclear medicine team will discuss this with you when you and your child arrive for the scan. You might also find it helpful to read this information about nuclear medicine from the Alliance for Radiation Safety in Pediatric Imaging
When are the results available?
A nuclear medicine doctor will send a report to your family doctor or paediatrician (child's doctor) within one or two working days of the scan. Please contact your family doctor to get the results. You will not be able to get the results from the nuclear medicine technologist.
- A lung perfusion scan tests how well blood flows to the lungs. A lung ventilation scan tests how well air and blood flow around the lungs.
- The lung ventilation scan involves breathing in and out a tiny amount of radioactive mist for five minutes before a special camera takes pictures of the lungs.
- The lung perfusion scan involves injecting a tiny amount of radioactive medicine into the blood and then taking pictures of the lungs to check how well it is reaching them.
- A nuclear medicine doctor will send the results of the scan to your family doctor or paediatrician (child's doctor) within two working days. The person who does the scan cannot give the results.