Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Leads of a right chest wall generator terminate in stable position . Mild cardiomegaly and mediastinal contours are stable . Medial left lower lobe opacity projecting over the lower thoracic spine on the lateral view is consistent with infection or atelectasis . No substantial pleural effusion or pneumothorax .
    OUTPUT:
    
Medial left lower lobe opacity consistent with atelectasis or pneumonia in the appropriate clinical setting .