CT diagnosis of segmental pulmonary artery embolus.

A patient with pathologically proven pulmonary embolism that was diagnosed on computed tomography (CT) is presented. The clot in an artery with a diameter less than 1 cm was clearly demonstrated as was an associated pulmonary infarct, which appeared hyperdense on contrast enhanced scan. The potential of CT to noninvasively demonstrate pulmonary embolism, particularly in smaller arteries, is discussed.