Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Focal opacity in left posterior costophrenic sulcus may reflect an area of atelectasis , scarring or pleural thickening ; a mass is less likely . Comparison to remote studies would be helpful . In their absence , followup imaging with a PA and lateral chest radiograph in ___ months to assess for stability would be prudent . Otherwise , there is no focal consolidation , large pleural effusion , pneumothorax , or pulmonary edema . The cardiomediastinal silhouette is within normal limits . Diffuse osteopenia is noted . No displaced rib fracture is identified .
    OUTPUT:
    
Focal opacity in the left posterior costophrenic sulcus as described above . Comparison to remote studies would be advised . In their absence , followup radiograph in ___ months would be prudent . Clinical correlation is also recommended .