Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: There bibasilar opacities and blunting of left costophrenic angle . There is no acute edema or pneumothorax . Median sternotomy wires and prosthetic aortic valve are again noted . Cardiomediastinal silhouette is within normal limits . No displaced fractures .
    OUTPUT:
    
Bibasilar opacities most suggestive atelectasis . Blunting of the left lateral costophrenic angle could also be due to atelectasis although superimposed effusion is possible .