Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Heart size within normal . No pleural effusions . A linear density is again noted in the anterior right chest . Narrowing of the transverse tracheal diameter . No focal consolidation or pneumothorax . No apparent chest wall abnormality .
    OUTPUT:
    
Although no acute fracture or other chest wall lesion is seen , conventional chest radiographs are not sufficient for detection or characterization of such abnormalities . If the demonstration of such a chest cage abnormality is clinically warranted , the location of any referrable focal findings should be clearly marked and imaged with either bone detail views or CT scanning . No acute cardiopulmonary process . Narrowing of the transverse tracheal diameter , probable saber sheath trachea , which is associated with chronic lung disease .