Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Frontal and lateral views of the chest are obtained . The subtle mild left base streaky opacity could represent atelectasis vs . pneumonia . The right lung is clear . There is no pleural effusion or pneumothorax . The cardiac and mediastinal silhouettes are unremarkable . The mediastinum is not widened .
    OUTPUT:
    
1 . Streaky left base opacity could represent atelectasis or early / mild pneumonia . 2 . Mediastinum is normal in appearance , is not widened .