Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: PA and lateral images of the chest . Lung volumes are somewhat low . There is an opacity at the left lung base which may represent atelectasis or focal pneumonia in the right clinical setting . Atelectasis is seen at the right lung base . No focal opacity or mass is seen . There may be a small right pleural effusion . There is no left pleural effusion or pneumothorax . The cardiomediastinal silhouette is unremarkable .
    OUTPUT:
    
Left lung base opacity which may represent atelectasis or focal infectious pneumonia .