Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: The lungs are clear . No focal consolidation , effusion , edema , or pneumothorax . Minimal atelectasis at the left lung base . Aortic knob calcifications are mild , unchanged . The heart size is normal , unchanged . The mediastinum is not widened . Mild dextroconvex scoliosis of the thoracic spine is overall unchanged . No evidence of aacute rib fracture on this nondedicated exam , but note is made of apparent healed lower rib fractures bilaterally at the left tenth and right ninth ribs . Multilevel degenerative changes of the thoracic spine are overall similar . Degenerative changes of the left AC joint are mild .
    OUTPUT:
    
1 . No acute cardiothoracic process . 2 . No evidence of rib fracture on this nondedicated exam . If clinical suspicion persists , consider dedicated rib radiographs .