Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: AP and lateral views of the chest are compared to previous exam from ___ . Since prior , there has been interval improved aeration at the left lung base . The lungs are clear of confluent consolidation or effusion . Cardiomediastinal silhouette is within normal limits . Elevation of the left hemidiaphragm is as seen on prior . Osseous structures again notable for lower cervical , upper thoracic anterior fixation hardware and probable posttraumatic and potentially post-surgical changes at the left shoulder including the acromioclavicular joint .
    OUTPUT:
    
No acute cardiopulmonary process .