Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Increased opacity in the posterior segment of the right lower lung compared to the prior exam . The lungs are otherwise clear and hyper - expanded . No pleural effusion , pulmonary edema , or pneumothorax . The cardiomediastinal silhouette , hila , and pleura are normal . No acute osseous abnormality .
    OUTPUT:
    
Increased opacity in the posterior segment of the right lower lung , which in the appropriate clinical setting could represent an acute pneumonia .