Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: In comparison to the chest radiographs obtained 5 days prior , small , bilateral pleural effusions are unchanged and there has been interval improvement of some parenchymal opacities seen on recent chest radiograph . ___ opacities appear to project over the anterior and posterior ribs , raising the possibility repetitive stress fractures in the setting of COPD and chronic cough . There are multiple old rib fractures , which appear unchanged . Heart size is normal without pulmonary edema .
    OUTPUT:
    
Patchy bilateral opacities may be due to some combination of multifocal pneumonia and / or rib stress fractures . Unchanged , small , bilateral pleural effusions .