Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: There is bibasilar atelectasis . Lung volumes are normal . There is mild cardiomegaly , similar to the prior study . There is no large pleural effusion or pneumothorax . There is mild prominence of the central pulmonary vasculature , but no frank pulmonary edema .
    OUTPUT:
    
Mild bibasilar atelectasis , similar to the prior chest radiograph .