What is considered the definitive test for confirming a pulmonary embolism (PE)?

A pulmonary angiogram is considered the definitive test for confirming a pulmonary embolism (PE) because it directly visualizes the blood vessels in the lungs. During this procedure, contrast dye is injected into the pulmonary arteries, allowing radiologists to capture images that clearly show any blockages or obstructions caused by emboli. This high level of specificity in identifying the presence of clots in the pulmonary vasculature makes the pulmonary angiogram the gold standard for diagnosing PE, particularly in cases where the diagnosis is uncertain based on other imaging studies.

While other imaging modalities like spiral CT scans can also be highly effective in diagnosing PE, they do not provide the same level of direct evidence as a pulmonary angiogram. Similarly, while V/Q scans and chest X-rays can suggest the presence of a PE, they are more indirect assessments and do not confirm the diagnosis with the same level of accuracy as an angiogram.