MEASUREMENTS OF PULMONARY VASCULAR-PERMEABILITY WITH PET AND GA-68 TRANSFERRIN

  • 1 November 1987
    • journal article
    • research article
    • Vol. 28  (11) , 1704-1716
Abstract
We quantified pulmonary vascular permeability with positron emission tomography (PET) and gallium-68- (68Ga) labeled transferrin. Six dogs with oleic acid-induced lung injury confined to the left lower lobe, two normal human volunteers, and two patients with the adult respiratory distress syndrome (ARDS) were evaluated. Lung tissue-activity measurements were obtained from sequential 1-5 min PET scans collected over 60 min, after in vivo labeling of transferrin through intravenous administration of [68Ga]citrate. Blood-activity measurements were measured from simultaneously obtained peripheral blood samples. A forward rate constant describing the movement of transferrin from pulmonary vascular to extravascular compartments, the pulmonary transcapillary escape rate (PTCER), was the calculated from these data using a two-compartment model. In dogs, PTCER was 49 .+-. 18 in normal lung tissue and 485 .+-. 114 10-4 min-1 injured lung. A repeat study in these dogs 4 hr later showed no significant change. Values in the human subjects showed similarly marked differences between normal and abnormal lung tissue. We conclude that PET will be a useful method of evaluating vascular permeability changes after acute lung injury.