Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Lung volumes are low accentuating the cardiac silhouette and vasculature . Heart size is borderline enlarged . There is re- demonstration of mild vascular congestion and interstitial edema . Subtle right base and retrocardiac opacities may represent atelectasis . Pleural surfaces are clear without effusion or pneumothorax . Sclerotic bone changes consistent with history of sickle cell .
    OUTPUT:
    
Low lung volumes with mild fluid overload and edema . Retrocardiac opacity may represent atelectasis though infection can not be excluded . Post - diuresis re-examination may be helpful .