• The superior segment of RLL , LLL and axillary sub-segments of anterior and posterior segments of RUL usually account for 85% of all aspiration lung abscesses. The lesions will correspond to these sites in CXR.
• In the early stages one sees consolidation.
• The inflammatory mass eventually necroses and the necrotic material is expectorated through bronchus.
• The cavity that results has thick wall with irregular lumen. You may note stalactites and stalagmites in the lumen.
• Air fluid level is the hall mark of Lung abscess.
• The appearance of the cavity is similar to necrotizing squamous cell cancer of lung and has to be differentiated from it.