Lung perfusion scan
When is this exam indicated?
- pulmonary embolism, to search for perfusion defects of segmental and subsegmental type with preserved ventilation;
- chronic bronchopneumopathies, to evaluate the perfusion/ventilation ratio associated with ventilatory scintigraphy;
- pulmonary neoplasms, to evaluate the pre-intervention (pneumectomy or lobectomy).
How is it performed?
The radiopharmaceutical used consists of human albumin macroaggregates with a diameter larger than that of the pulmonary capillaries and marked with Tc-99m pertechnetate. It is injected intravenously and is distributed into the pulmonary circulation via the pulmonary arteries in proportion to regional blood flow.
No preparation is required by the patient.
The examination lasts about 20 minutes.
A chest X-ray is essential for this examination.
Severe pulmonary hypertension.