Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: The cardiomediastinal and hilar contours are within normal limits . The lung fields are clear . A subtle transverse lucency through the superior sternum is suspicious for a nondisplaced sternal fracture . There is no pneumothorax , fracture or dislocation . Limited assessment of the abdomen is unremarkable .
    OUTPUT:
    
A subtle lucency through the superior sternum is suspicious for a nondisplaced sternal fracture .