Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Frontal and lateral radiographs of the chest demonstrates slightly decreased lung volume since the prior study . There is subtle opacification at the left lung base which is new since the prior study and may represent atelectasis or developing pneumonia . The heart size , hilar and mediastinal contours are unchanged . No pleural abnormality is identified .
    OUTPUT:
    
Subtle left lower lobe opacity which is new since the prior radiograph and may represent consolidation versus atelectasis . Recommend oblique views for further characterization of the left lower lobe . These findings were relayed to Dr . ___ , by Dr . ___ , at 12 :41 . In lieu of additional views , the patient had already been started on antibiotics .