Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: As compared to prior chest radiograph from ___ , lung volumes remain low . There is increased retrocardiac density and increased density at the right lung base , most suggestive of atelectasis . Small bilateral pleural effusions are likely present . There is no pneumothorax . The cardiomediastinal and hilar contours are unchanged .
    OUTPUT:
    
1 . Retrocardiac and right lung base densities , most suggestive of atelectasis . However , close monitoring is recommended . 2 . Probable small bilateral pleural effusions .