Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: The heart size is unchanged . Mediastinal contours are stable . Pulmonary vasculature is normal . Low lung volumes may account for left lower lobe opacities , which are also present prior on the prior film . No focal consolidations concerning for pneumonia are present . No pneumothorax or pleural effusion .
    OUTPUT:
    
No evidence of pneumonia .