Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: The lungs are clear without consolidation , pleural effusion or pneumothorax . The heart size is normal . The aortopulmonary window is indistinct which could be due to adenopathy . Widening of the right paratracheal stripe may be due to a lymphadenopathy or dilated esophagus .
    OUTPUT:
    
Widening of the right paratracheal stripe and abnormality of the left mediastinal contours are of uncertain etiology . Further evaluation with chest CT is recommended .