Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: AP upright and lateral views of the chest were obtained . Heart is normal in size and cardiomediastinal contour is stable . Extensive calcifications are noted in the aortic arch . Left lower lobe opacities are better characterized on the subsequent chest CT and may relate to pneumonia or aspiration . The lungs are otherwise clear . There is no pleural effusion or pneumothorax .
    OUTPUT:
    
Left lower lobe opacities , better characterized on the subsequent CT , may relate to foci of aspiration or infection .