Who Needs a Lung Ventilation/Perfusion Scan?

People who have signs or symptoms of a pulmonary embolism (PE) may need lung ventilation/perfusion (VQ) scans.

A PE occurs when a blood clot travels to the lungs and blocks blood flow. Signs and symptoms of PE include chest pain, trouble breathing, rapid breathing, coughing, coughing up blood, and a rapid heart rate. Some clots travel to the lungs from veins deep in the legs. This can cause pain and swelling in the affected limb(s).

Doctors use VQ scans to help find out whether a PE is causing these signs and symptoms. A VQ scan alone, however, won’t confirm whether you have PE. Your doctor also will consider other factors when making a diagnosis.

Doctors also use VQ scans to detect poor blood flow in the lungs’ blood vessels and to examine the lungs before some types of surgery.