Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Frontal and lateral views of the chest . Normal lungs , pleural and mediastinal surfaces . Top normal heart size . No free air beneath the hemidiaphragms . Healed old rib fractures are noted in the posterior right fifth rib and the sixth and seventh posterior left ribs .
    OUTPUT:
    
No acute intrathoracic process . Top normal heart size .