Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Single supine view of the chest . Linear left basilar opacity is likely due to atelectasis . Elsewhere , the lungs are clear . There is no evidence of a large pneumothorax based on the supine film . The cardiomediastinal silhouette is stable . No displaced fractures identified based on this non-dedicated exams . Median sternotomy wires are again noted as well as an aortic valve replacement . Deviation of the trachea to the right at the thoracic inlet is compatible with left - sided thyroid enlargement as seen on prior CT chest .
    OUTPUT:
    
No definite acute cardiopulmonary process based on a portable film .