Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Low lung volumes . Unchanged mild cardiomegaly . The mediastinal and hilar contours are unremarkable . Bibasilar opacities may reflect atelectasis , but infection or aspiration can not be excluded . There is mild blunting of the costophrenic on the right which may represent a small pleural effusion . No pneumothorax is visualized on this semi-upright radiograph . There are no acute osseous abnormalities . Surgical clips are visualized superior to the right clavicle . There is a healed left clavicle fracture .
    OUTPUT:
    
Bibasilar airspace opacities , possibly representing atelectasis with aspiration and pneumonia not excluded . Small right pleural effusion .