Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: PA and lateral views of the chest provided . Mild narrowing of the upper trachea is unchanged from chest radiograph ___ . There is borderline hyperinflation of the lungs . There is no focal consolidation , effusion , or pneumothorax . The cardiomediastinal silhouette is normal . Imaged osseous structures are intact . No free air below the right hemidiaphragm is seen .
    OUTPUT:
    
1 . Lungs are clear without evidence of pulmonary edema . 2 . Mild narrowing of the upper trachea is unchanged from chest radiograph ___ . This is most commonly seen secondary to goiter or prior tracheostomy .