Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: PA and lateral views of the chest provided . Lungs are clear . Pulmonary vasculature is normal . Heart size is normal . Again seen is an air - filled structure overlying the trachea , not well evaluated on this lateral view .
    OUTPUT:
    
Incompletely assessed air-filled structure overlying the trachea . Lateral neck radiograph may be obtained if further investigation is warranted .