Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Patchy right base opacity raises concern for pneumonia versus possibly atelectasis . The left lung is clear . No pleural effusion or pneumothorax is seen . The cardiac silhouette appears top - normal . Mediastinal contours are unremarkable . No pulmonary edema is seen .
    OUTPUT:
    
Right base opacity could be due to pneumonia versus atelectasis .