title: Prestenotic bronchial radioaerosol deposition: a new ventilation scan sign of bronchial obstruction.
abstract: This study was performed to assess the diagnostic usefulness of aerosol ventilation scanning in bronchial obstruction and bronchial stenosis.
  
  
  METHODS
  Seven patients of bronchial obstruction and one patient with stenosis were studied. In each patient, obstruction was confirmed by bronchography, bronchoscopy and/or CT scan. Ventilation scanning was performed using the 99mTc-phytate aerosol generated by a BARC jet nebulizer. Scan manifestations were assessed in correlation with those of plain chest radiography, bronchography, CT scan and/or bronchoscopy.
  
  
  RESULTS
  In every patient, the ventilation scan showed characteristic intense aerosol deposition in a short, slightly dilated, clubbed, bronchial segment immediately proximal to obstruction or stenosis. Typically, it was accompanied by a distal airspace deposition defect.
  
  
  CONCLUSIONS
  Intense, segmental, bronchial aerosol deposition with distal lung defect was a specific finding of bronchial obstruction and stenosis. The sign was especially useful when obstruction was obscured by the associated, bizarre lung disease and in a small bronchus.
authors.affiliation: Department of Radiology, Kangnam St. Mary's Hospital, Catholic University Medical College, Seoul, Korea.
authors.forename: S K
authors.initials: SK
authors.lastname: Chung
authors.forename: H H
authors.initials: HH
authors.lastname: Kim
authors.forename: Y W
authors.initials: YW
authors.lastname: Bahk
mesh_terms: D000336:Aerosols; D000368:Aged; D001982:Bronchial Diseases / Q000000981:diagnostic imaging*; D003251:Constriction, Pathologic / Q000000981:diagnostic imaging; D005260:Female; D006801:Humans; D008173:Lung Diseases, Obstructive / Q000000981:diagnostic imaging*; D008297:Male; D008875:Middle Aged; D015609:Organotechnetium Compounds / Q000008:administration & dosage; D010833:Phytic Acid / Q000008:administration & dosage; D011877:Radionuclide Imaging
chemical_list: D000336:Aerosols; D015609:Organotechnetium Compounds; C026177:technetium phytate; D010833:Phytic Acid