Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Leftward shift of mediastinal structures with tenting of the left hemidiaphragm is compatible with left sided volume loss as a result of prior left upper lobectomy . Heart size appears mildly enlarged . The aorta is slightly tortuous . Pulmonary vasculature is normal . Blunting of the left costophrenic angle likely reflects a small left pleural effusion . Atelectatic changes are noted in the left lung base . Right lung is clear . No pneumothorax is identified . Multilevel degenerative changes are noted in the thoracic spine with anterior osteophytes . Remote left - sided rib fractures are present
    OUTPUT:
    
Postsurgical changes in the left lung . Small left pleural effusion and left basilar atelectasis .