Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Single frontal view of the chest is highly limited due to underpenetration . Allowing for such , no pneumothorax is detected . The cardiomediastinal silhouette is mildly prominent , but likely accentuated by low lung volumes and AP technique . Assessment of the lungs is limited , but retrocardiac opacities persist .
    OUTPUT:
    
Limited exam demonstrating no obvious pneumothorax .