Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Compared with the prior film , there has been progressive opacification in the retrocardiac region , with new near - complete obscuration of the left hemidiaphragm . There likely reflects a moderate size left pleural effusion , with underlying collapse and / or consolidation . Mild atelectasis at the right lung base medially is noted . Mediastinum remains midline . No CHF . Minimal blunting of the right costophrenic angle is compatible with a small right pleural effusion , improved compared with the prior film .
    OUTPUT:
    
New retrocardiac opacification , likely reflecting a combination of pleural fluid , together with atelectasis and / or consolidation .