Lung Perfusion and Ventilation Scintigraphy (V/Q Scan)
Scintigraphic assessment of the lungs is performed in two sessions:
- Lung perfusion scintigraphy, in which the blood flow to the lung fields is depicted.
- Lung ventilation scintigraphy, which shows the regional ventilation of the lungs.
Both examinations can be performed separately or in combination (2 in 1) depending on the referring physician's requirements and the substances used.
When is this examination necessary?
Lung scintigraphy is often performed if pulmonary embolism is suspected, to assess quantitative relative functions of various lung fields before lung surgery and to clarify the presence of a right-to-left shunt.
How do you prepare for lung scintigraphy?
Special preparation is not necessary, you do not have to be in a fasting state and do not need to stop taking your medications prior to the examination. It is important that you bring your insurance card, referral form and, if available, X-rays of your lungs with you on the examination day.
How does the examination work?
Perfusion scintigraphy:
For this examination, you will be injected radioactively marked small protein particles into an arm vein, which accumulates in your lungs depending on the blood flow. This enables us to visualize lung blood flow distribution and show areas of interrupted perfusion due to a possible lung embolism or a space-occupying lesion with the help of our special cameras (gamma cameras) after the injection.
Ventilation scintigraphy:
The ventilation images can be used to visualize the ventilation conditions. Patient inhales a the radioactive gas with low-level radiation through a breathing mask and lung images are acquired while the patient inhales. The actual examination takes about 15 minutes. It would be possible to make sectional images of the lung (SPECT) to make the findings more clear. This additional examination requires an additional acquisition for 30 minutes and does not involve an additional injection of the radiopharmaceutical. Following the examination, the physician will evaluate the images and prepare a detailed written report to be sent to the referring physician within a few days.
Do I have an increased risk regarding radiation exposure?
Radioactive substances are used in this examination, hence, the patient is exposed to a certain amount of radiation. Here the benefit-risk ratio must always be considered, the effective radiation dose of this examination is relatively low at approx. 1.1 - 2.2mSv. As a comparison, the amount of natural radiation exposure in Germany, to which everyone is exposed, is on average at an effective dose of 2.1mSv/year.
