Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: The lungs are hyperinflated . Patchy opacities at the bases bilaterally likely reflect atelectasis , however an underlying pneumonia can not entirely be excluded . Otherwise , the lungs are clear . Small left pleural effusion . No pulmonary edema . There is moderate cardiomegaly with calcifications of the aortic knob . No pneumothorax .
    OUTPUT:
    
Small left pleural effusion with patchy opacities at the bases bilaterally , likely representing atelectasis , however an underlying pneumonia can not be entirely excluded .