Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Frontal and lateral views of the chest . When compared to prior , there has been significant opacification of the inferior left hemithorax likely due to large pleural effusion . There is mediastinal shift to the right . The left lung apex and right lung remain clear . There is trace right pleural effusion as well . Cardiac silhouette can not be assessed given silhouetting on the left . No acute osseous abnormality is identified .
    OUTPUT:
    
Opacification of the lower left hemithorax with mass effect to the right in part due to large pleural effusion with suspected underlying atelectasis , underling infection is also possible .