Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: A moderate size left pleural effusion appears slightly increased in size compared to the prior radiograph , with a component appearing to be loculated laterally . Opacification within the left lung base may reflect compressive atelectasis though infection is not completely excluded . Assessment of the cardiac silhouette size is difficult given the presence of the left pleural effusion . The aortic knob is calcified . Hazy opacification with in the right lung base may be due to overlying soft tissue . There is no pneumothorax or pulmonary edema . No acute osseous abnormality is seen .
    OUTPUT:
    
Moderate size left pleural effusion , slightly larger than on the prior study . Left basilar opacification likely reflects compressive atelectasis , but infection can not be completely excluded .