Alveolar consolidation detection: Advanced multiple beam equalization radiography versus conventional chest radiography

Advanced multiple beam equalization radiography (AMBER) and conventional chest radiography were prospectively evaluated in the detection and quantitation of alveolar (air-space) consolidation. Thirty-seven healthy volunteers underwent bronchoalveolar lavage (BAL), the retained lavage fluid serving as a model for alveolar consolidation. After BAL, the subjects underwent AMBER and conventional chest radiography. The lower lung zones on the radiographs were divided into four zones and graded for alveolar consolidation by three observers. There was no significant difference in the area under the receiver operating characteristic curve between the two techniques in the detection of lavage fluid. The grade of opacification was rated significantly higher (P < .05) on conventional radiographs for three of the four lung zones examined, and the correlation between the quantity of retained lavage fluid and grade of opacity was better on conventional radiographs. Detection of lavage fluid was poor with either technique. The exposure compensation of AMBER was evident in this model of air-space disease but did not affect overall obsever performance.