title: The utility of fractional wash-out slope values following intravenous 133Xe.
abstract: The regional clearance of 133Xe from the lungs after intravenous administration as well as following rebreathing was assessed in 7 normals and 18 patients with various lung disorders. Each lung was divided into three zones as upper, middle and lower. Regional ventilation (V) and regional perfusion (P) were determined using the area under the first peak at the beginning of the ventilation study and the area under the peak after intravenous administration, respectively. Slopes were calculated using the first exponential of the wash-out curve. Absolute slope values of the wash-out curves after perfusion (Pwo) and ventilation (Vwo) were expressed as a percentage of the total for each lung. Correlation coefficients between V and Vwo, V and Pwo, P and Pwo were .695, .584 and .882 in normals and .610, .461 and .685 in patients, respectively. It is concluded that Pwo is influenced by both perfusion and ventilation; it may reflect the fractional contribution to the gas exchange and can be used in the prediction of residual lung function after lung resection.
authors.affiliation: Department of Nuclear Medicine, Hacettepe University, Faculty of Medicine, Ankara, Turkey.
authors.forename: H
authors.initials: H
authors.lastname: Durak
authors.forename: C F
authors.initials: CF
authors.lastname: Bekdik
authors.forename: N
authors.initials: N
authors.lastname: Ulutuncel
mesh_terms: D000280:Administration, Inhalation; D000328:Adult; D000368:Aged; D005260:Female; D006801:Humans; D007275:Injections, Intravenous; D008173:Lung Diseases, Obstructive / Q000000981:diagnostic imaging / Q000503:physiopathology*; D008297:Male; D008875:Middle Aged; D011877:Radionuclide Imaging; D014692:Ventilation-Perfusion Ratio / Q000502:physiology*; D014980:Xenon Radioisotopes / Q000008:administration & dosage
chemical_list: D014980:Xenon Radioisotopes