Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: The heart is normal in size . The mediastinal and hilar contours appear within normal limits . There is no pleural effusion or pneumothorax . Streaky opacity is present at the left lung base which tethers the hemidiaphragm upward somewhat suggesting minor atelectasis . Elsewhere , the lungs appear clear . There is no pleural effusion or pneumothorax .
    OUTPUT:
    
Left basilar opacity with volume loss more suggestive of minor atelectasis than an infectious process . Correlation with clinical circumstances is suggested .