Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: The heart size is normal . The mediastinal and hilar contours are unremarkable . Within the left mid lung field medially , there is a new , approximately 2 - cm focal opacity identified which is nonspecific but could reflect an area of infection . The right lung is clear . Pulmonary vascularity is normal . No pleural effusion or pneumothorax is identified . Multiple clips in the right upper quadrant indicate prior cholecystectomy .
    OUTPUT:
    
New focal opacity in the left mid lung field , not seen on the prior studies . This is nonspecific but could reflect an area of infection . Follow radiographs are recommended after treatment to ensure resolution of this finding .