Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Left retrocardiac opacity is seen which raises concern for pleural effusion with possible atelectasis underlying consolidation not excluded . However , there appears to be some lucencies within the region of opacity which could be due to necrosis / infection however , hernia with bowel content is not entirely excluded . The right lung is clear . No pneumothorax seen . The aortic knob is calcified .
    OUTPUT:
    
Left basilar opacity could be due to combination of pleural effusion and atelectasis , underlying consolidation not excluded . However , there are also appear to be subtle areas of lucency within and necrosis / other infection or herniated GI tract is not excluded . Dedicated PA and lateral views would be helpful for further evaluation if patient able .