Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: There is patchy medial left upper lung opacity and mild elevation of the left hemidiaphragm , in combination may represent left upper lobe atelectasis . However , consolidation due to pneumonia may also be present . No pleural effusion or pneumothorax is seen . The cardiac silhouette is stable in size and unremarkable .
    OUTPUT:
    
Concern for left upper lobe atelectasis / partial collapse ; however , left upper to mid lung opacity could also relate to pneumonia . Recommend followup to resolution .