Lung scintigraphy is a medical imaging study into the blood flow in the lungs and the air flow in the airway of the lungs. Use is made of a radioactive substance which is brought into the body. The examination is carried out in order to detect or exclude disease processes in the lungs.
The examination provides information about any lung defects. The doctor may, for example, find a blood clot (pulmonary embolism). A lung scintigraphy can also serve as preparation for lung surgery.
Lung scintigraphy is an imaging technique, in which use is made of a radioactive substance which is administered to the patient. The radioactive substance ensures that radiation is released. This radiation can be measured. A radioactive substance has the property to accumulate at certain places in the body, for example at the location of a defect. By looking at where the radioactive substance ends up, these defects can be located.
A lung scintigraphy usually includes two parts:
- Lung perfusion scan. With this examination, the doctor analyzes the blood flow in the lung. The patient is lying on an examination table. The doctor injects a low-radioactive liquid into the arm. The patient should deeply inhale and exhale a few times to distribute the liquid properly. Shortly after the injection, a gamma camera takes pictures of the lungs in different directions. This takes about 10 minutes.
- Lung ventilation scan. With this examination, the doctor analyzes how inhaled gas is distributed over the lungs. While the patient is sitting, he or she inhales radioactive gas via a cap for a few minutes. The gas is mixed with normal air, so the patient can simply breathe. In the meanwhile, the gamma camera takes pictures of the lungs again. This also takes about 10 minutes.
The examination doesn’t hurt. Within 24 hours, the radioactive substance has disappeared from the body. This can be speeded up by drinking a lot.