Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Single frontal view of the chest . Left subclavian central line terminates in the mid SVC . Median sternotomy wires and mediastinal surgical clips are noted . There is an opacity at the right lung base , at least part of which looks like is due to pleural fluid tracking along the fissure . Medially , the opacity may represent focal atelectasis , but can not rule out pneumonia or aspiration in the right clinical setting . The lungs are otherwise clear . There is no left pleural effusion . No pneumothorax is seen . The cardiomediastinal silhouette is unremarkable .
    OUTPUT:
    
1 . Right lung base opacity , which may represent atelectasis but can not exclude pneumonia versus aspiration in the right clinical setting . 2 . Small right pleural effusion .