Understanding Lung Perfusion & Ventilation Scans: Alternative Names

Lung perfusion and ventilation scans are collectively referred to as:

• Ventilation‑Perfusion Scan or V/Q Scan
• Perfusion Lung Scan (perfusion component alone)
• Ventilation Lung Scan (ventilation component alone)
• Pulmonary V/Q Scan
• Lung V/Q Study

The V/Q scan compares air distribution (ventilation, using inhaled radioactive gas/aerosol) with blood flow (perfusion, using IV radiolabeled albumin macroaggregates). Mismatched defects (ventilation normal, perfusion absent) suggest pulmonary embolism. Matched defects suggest COPD, pneumonia, or other parenchymal disease.