Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Study is somewhat limited due to patient rotation . Heart size is difficult to assess but appears at least mildly enlarged . Opacity adjacent to the aortic knob could potentially reflect a pseudoaneurysm of the aortic arch or other mass lesion . Mild bibasilar atelectasis is demonstrated . No large pleural effusion or pneumothorax is seen . There is no pulmonary edema . There is diffuse demineralization of the osseous structures with loss of height of a vertebral body of the thoracolumbar junction . Mild S - shaped scoliosis of the thoracolumbar spine is present . The right humeral head has been resected .
    OUTPUT:
    
Opacity adjacent to the aortic knob is concerning for a pseudoaneurysm or other mediastinal lesion and further assessment with CT of the chest is recommended if not done previously . Mild bibasilar atelectasis .