Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Since earlier ___ chest radiograph , there is no interval change of known left pneumothorax . Left chest tube is in unchanged position . No evidence of tension . Right lung is clear . The cardiomediastinal silhouette is stable . No pleural effusion .
    OUTPUT:
    
1 . Unchanged appearance of known left pneumothorax since earlier same day chest radiograph .