LUNG PERFUSION SCAN

Course overview

A VENTILATION-PERFUSION (VQ) SCAN IS A DIAGNOSTIC TEST USING RADIOISOTOPES TO EVALUATE LUNG PERFUSION AND VENTILATION. VENTILATION-PERFUSION SCAN CONSISTS OF TWO PORTIONS, A VENTILATION (V) SCINTIGRAPHY AND A PERFUSION (Q) SCINTIGRAPHY. VENTILATION SCINTIGRAPHY INVOLVES ADMINISTERING A RADIOACTIVE ISOTOPE TO ASSESS LUNG VENTILATION, AND PERFUSION SCINTIGRAPHY USES AN INJECTABLE TRACER AND ASSESSES ITS DISTRIBUTION TO THE LUNG VASCULATURE. WHILE CT PULMONARY ANGIOGRAPHY IS CURRENTLY CONSIDERED THE GOLD STANDARD AND IS ONE OF THE MOST COMMONLY USED MODALITIES FOR DIAGNOSING PULMONARY EMBOLISM, A V/Q SCAN IS USEFUL IN ASSESSING THE LIKELIHOOD OF PULMONARY EMBOLISM WHEN INTRAVENOUS CONTRAST IS CONTRAINDICATED. ITS MOST COMMON CLINICAL USE IS IN THE WORKUP OF SUSPECTED PULMONARY EMBOLISM. THIS ACTIVITY REVIEWS THE USE OF A VQ SCAN IN EVALUATING PULMONARY EMBOLISM AND OTHER CLINICAL SCENARIOS.