Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Frontal and lateral views of the chest demonstrate clear lungs . The rounded density at the costochondral junction of the left first rib is again seen and has been proven on prior CTs to be due to degenerative changes at the costochondral junction . Cardiac and mediastinal contours are normal . No pleural abnormalities seen .
    OUTPUT:
    
No acute cardiopulmonary process .