Pulmonary scintigraphy is a diagnostic test that assesses the presence of changes in the passage of air or blood circulation to the lungs, being performed in 2 steps, called inhalation, also known as ventilation, or perfusion. To perform the exam, it is necessary to use a medication with radioactive capacities, such as Tecnécio 99m or Gallium 67, and a device to capture the formed images.
The pulmonary scintigraphy exam is indicated, mainly, to help the diagnosis and treatment of pulmonary embolism, but also to observe the existence of other pulmonary diseases, such as infarction, pulmonary emphysema or deformities in blood vessels, for example.
Where it is done
The pulmonary scintigraphy exam is done in imaging clinics that contain this device, and can be done free of charge, if requested by a SUS doctor, as well as in private clinics through the health plan or by paying the amount that is, on average, R $ 800 reais, which varies depending on the location.
What is it for
Pulmonary scintigraphy is used in the following cases:
- Pulmonary thromboembolism, for diagnosis and control of the disease, as the main indication. Understand what is and what can cause pulmonary embolism; Observe areas of the lungs where there is not adequate ventilation, a situation called pulmonary shunt; Preparation of lung surgery, by observing the blood circulation of the organ; Identify causes of unclear lung diseases, such as emphysema, fibrosis or pulmonary hypertension; evaluation of congenital diseases, such as malformations in the lungs or blood circulation.
Scintigraphy is a type of test that is also performed to look for changes in other organs, such as kidneys, heart, thyroid and brain, for example, helping to observe various types of changes, such as cancer, necrosis or infections. Learn about the indications and how bone scans, myocardial scans and thyroid scans are done.
How it is made and prepared
Pulmonary scintigraphy is done in 2 steps:
- 1st stage - Ventilation or Inhalation: it is done with the inhalation of saline containing the radiopharmaceutical DTPA-99mTc that is deposited in the lungs, to then form the images that are captured by the device. The examination is done with the patient lying on a stretcher, avoiding moving, and lasts about 20 minutes. 2nd stage - Perfusion: performed with an intravenous injection of another radiopharmaceutical, called MAA marked with technetium-99m, or in some specific cases Gallium 67, and images of the blood circulation are also taken with the patient lying down, for about 20 minutes.
It is not necessary to fast or any other specific preparation for the pulmonary scintigraphy, however, it is important on the day of the exam to take other tests that the patient has done during the investigation of the disease, to help the doctor to interpret and interpret the result of a more accurately.