[Early changes in acute pulmonary embolism as seen in the scintigram and on x-ray film (author's transl)].

Pulmonary embolism is among the most frequent acute pulmonary diseases. Non-invasive radiological diagnosis can make use of the x-ray film of the chest and of the various forms of scintigraphy of the lungs. The authors compared the non-invasive approaches in 328 patients clinically suspected of acute pulmonary embolism. Compared with computerized ventilation/perfusion scintigraphy, evaluation of perfusion scintigraphy shows an "over-diagnostis" of pulmonary embolism by 60% (148) "detected cases" in 92 patients). 16% of all patients with no abnormal findings in their x-ray film had acute pulmonary embolism, in another 17% we found perfusion defects pointing towards embolism, associated with a disturbance of ventilation. To exclude pulmonary embolism, performance of perfusion scintigraphy will suffice; studies of ventilation will be mandatory to establish proof that embolism is present. Indirect roentgenographic signs are not helpful in arriving at the correct diagnosis.