Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Cardiac silhouette size is normal . The aorta is tortuous . The mediastinal and hilar contours otherwise are unremarkable . Pulmonary vasculature is normal . Apart from subsegmental atelectasis within the right middle lobe , the lungs are clear without focal consolidation , pleural effusion or pneumothorax . Rounded opacity projecting over the distal clavicle could reflect a bone island or area of heterotopic ossification .
    OUTPUT:
    
No acute cardiopulmonary abnormality .