title: The incidence and etiology of the ventilation/perfusion reverse mismatch defect.
abstract: Kr-81m ventilation and Tc-99m perfusion images of 392 patients were examined retrospectively for the incidence and etiology of the reverse mismatch defect, which is characterized by a region of lung where the perfusion defect exceeds the ventilation defect. Forty-six patients (11.7%) showed such defects. The most frequent causes were pneumonia (15%), atelactasis (15%), pleural effusions (15%), chronic obstructive airway disease (24%), and bronchial obstruction (31%). The significance of the reverse mismatch defect is discussed.
authors: Department of Radiology, Hammersmith Hospital, London.
authors: P
authors: P
authors: Carvalho
authors: J P
authors: JP
authors: Lavender
mesh_terms: D000328:Adult; D000368:Aged; D005260:Female; D006801:Humans; D008171:Lung Diseases / Q000000981:diagnostic imaging* / Q000503:physiopathology; D008173:Lung Diseases, Obstructive / Q000000981:diagnostic imaging; D008297:Male; D008875:Middle Aged; D010996:Pleural Effusion / Q000000981:diagnostic imaging* / Q000503:physiopathology; D011877:Radionuclide Imaging; D012189:Retrospective Studies; D013667:Technetium; D014692:Ventilation-Perfusion Ratio
chemical_list: D013667:Technetium