Perfusion Scintigraphy Compared With Pulmonary Arteriography in the Diagnosis of Pulmonary Embolism

Abstract

From August 1976 through February 1978, 108 suspected cases of pulmonary embolism were studied. In 31 patients, the scintigraphic diagnosis and the findings of pulmonary emboli detected at pulmonary arterial angiography were compared in order to assess the specificity of pulmonary scanning. Of the 108 patients in whom pulmonary embolism had been diagnosed by perfusion lung scan, 77 did not undergo pulmonary angiography: 46 because angiography was not available, 27 because of very severe illness, and four because of the opposition from relatives or from the attending physician. In the remaining 31 patients, a total of 36 pulmonary angiographies were performed, and the results compared with the corresponding perfusion scan findings. In four patients, the contrast media was injected into the main pulmonary artery; the remaining 32 examinations were performed after positioning the injection catheter at different lobar branches, chosen on the basis of the perfusion lung scan findings. In six patients, pulmonary arterial angiography was performed after pulmonary embolism had been treated by continuous heparin infusion, when all of them showed significant improvement in the perfusion lung scan pattern (in five cases pulmonary angiography had also been performed previously, at the time of early diagnosis).