Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Heart size is normal . Mediastinal and hilar contours are within normal limits . Pulmonary vasculature is normal . There is subsegmental atelectasis noted in both lung bases without focal consolidation . No pleural effusion or pneumothorax is present . No acute osseous abnormality is detected .
    OUTPUT:
    
Bibasilar subsegmental atelectasis . No definite displaced rib fracture is seen .