Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Lung volumes are somewhat low , accentuating the heart size , which is top - normal . A likely small left pleural effusion is seen best on the lateral view . No pulmonary edema , pneumothorax , or focal consolidation worrisome for pneumonia . Left upper posterior lateral rib deformity is unchanged . A posterior spinal fusion construct is again noted , unchanged . Rounded opacity projecting over the heart shadow is necklace medallion , seen on the lateral view , external to the patient .
    OUTPUT:
    
Likely small left pleural effusion , seen best on the lateral view . No acute cardiopulmonary process .