Non-Invasive Diagnosis of Pulmonary Embolism

摘要

The noninvasive nature of diagnosing pulmonary embolism was investigated along two lines: labeling of platelets with 111-Indium oxine as a tracer to identify pulmonary embolism by gamma camera imaging and by determination of Platelet Factor-4 release from platelets in patients with confirmed venous thromboembolism. Primary effort was devoted to platelet labeling and imaging. Platelets harvested from dogs and humans were incubated with 111-Indium-8-hydroxyquinoline for approximately 50-90 minutes, after which the labeling efficiency was determined to be 69%, ranging from 25-98%. Ten dog platelet preparations labeled with 111 Indium oxine were injected into separate dogs in which experimental pulmonary emboli were previously produced. Four of the animal preparations showed a positive nuclear scan image identifying pulmonary emboli, 3 were inconclusive and 3 were negative. Multiple views consisting of anterior, posterior, right and left lateral scan views demonstrated the emboli in the 4 positive studies. Investigations into Platelet Factor-4 release from platelets in patients with confirmed venous thromboembolism showed some correlation with the acuity of the thrombotic event and tended to decrease with treatment and subsidence of the clinical process. Inadequate numbers, however, preclude any sound interpretation of these results.