Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Lung volumes are reduced compared to the previous exam . The heart size is mildly enlarged , but accentuated due to the presence of low lung volumes . Mediastinal and hilar contours are unremarkable . There is crowding of the bronchovascular structures , and possible mild pulmonary vascular congestion may be present . There is no focal consolidation , pleural effusion or pneumothorax identified . Patchy opacities in the lung bases are likely reflective of atelectasis . Diffuse demineralization of the osseous structures is again noted .
    OUTPUT:
    
Low lung volumes . Probable mild bibasilar atelectasis and possible minimal pulmonary vascular congestion .