Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: PA and lateral views of the chest are compared to previous exam from ___ . Since prior , tracheostomy tube is no longer seen . The lungs are clear . Costophrenic angles are sharp . Mild scarring vs . atelectasis in the left lower lobe noted . Elevation of the right hemidiaphragm is stable . The cardiomediastinal silhouette is stable as are the osseous and soft tissue structures .
    OUTPUT:
    
No acute cardiopulmonary process .