Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Lung volumes are low . A focal patchy opacity overlying the lung bases posteriorly best seen on lateral view may represent atelectasis given the low lung volumes , however pneumonia can not be excluded . No pleural effusion or pneumothorax . Doubt CHF . Right hemidiaphragm is elevated , similar to ___ . No free air seen beneath the diaphragms .
    OUTPUT:
    
A consolidation overlying the lung bases best seen on lateral view may represent atelectasis given the low lung volumes , however pneumonia can not be excluded .