Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Frontal and lateral radiographs of the chest demonstrate clear lungs . The heart , mediastinal and hilar contours are normal . No pleural abnormality is detected . On the lateral view , there is prominence of the posterior tracheal stripe which when compared to prior MR and CT scans of the cervical spine , demonstrate no focal abnormality .
    OUTPUT:
    
No acute cardiopulmonary process .