title: Matched ventilation-perfusion becomes mismatched ventilation-perfusion lung imaging after resolution of carcinoma of the bronchus.
abstract: Airway occlusion results in regional alveolar hypoxia followed by reflex hypoxic pulmonary arterial constriction. Ventilation-perfusion imaging demonstrates matched defects. In the two patients reported, occlusion of the main bronchus by bronchogenic carcinoma was resolved--in one case by radiation therapy, and in the other by removal of the tumor mass in the bronchus by bronchial slitted biopsy. The initially matched ventilation-perfusion findings became mismatched. While ventilation was presumed to be normal, pulmonary perfusion was not completely reversed.
authors.affiliation: Nuclear Medicine Service, Veterans Affairs Medical Center, Lexington, Kentucky 40511.
authors.forename: W J
authors.initials: WJ
authors.lastname: Shih
authors.forename: M L
authors.initials: ML
authors.lastname: Dillon
mesh_terms: D000368:Aged; D002289:Carcinoma, Non-Small-Cell Lung / Q000000981:diagnostic imaging* / Q000503:physiopathology / Q000628:therapy; D002294:Carcinoma, Squamous Cell / Q000000981:diagnostic imaging* / Q000503:physiopathology / Q000628:therapy; D006801:Humans; D006976:Hypertension, Pulmonary / Q000000981:diagnostic imaging* / Q000209:etiology; D008168:Lung / Q000000981:diagnostic imaging*; D008175:Lung Neoplasms / Q000000981:diagnostic imaging* / Q000503:physiopathology / Q000628:therapy; D008297:Male; D011877:Radionuclide Imaging; D013668:Technetium Tc 99m Aggregated Albumin; D014692:Ventilation-Perfusion Ratio / Q000502:physiology; D014980:Xenon Radioisotopes
chemical_list: D013668:Technetium Tc 99m Aggregated Albumin; D014980:Xenon Radioisotopes