Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: There is a small left upper lobe opacity , which appears significantly improved compared to ___ . Otherwise , the remainder of the lungs are free of consolidations , effusions or pneumothorax . The cardiomediastinal silhouette is within normal limits . No acute osseous abnormalities .
    OUTPUT:
    
Small left upper lobe opacity that has improved since ___ and likely represents resolving pneumonia .