Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: There are bilateral brain stimulator generators . Lung volumes are low . Bibasilar opacities may represent compressive atelectasis , although aspiration should be considered in the appropriate clinical setting . No other focal consolidation , pleural effusion or pneumothorax . The 1 .2 cm left retrocardiac nodule is re-demonstrated . Cardiomediastinal silhouette is within normal limits .
    OUTPUT:
    
1 . Bibasilar opacities likely represent subsegmental atelectasis , although a small area of focal consolidation and pneumonia can not definitely be excluded . 2 . Persistent 1 .2 cm left retrocardiac nodule , similar to ___ .