Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: The small left apical pneumothorax has decreased in size now measuring 12 mm compared with 16 mm this morning . There is no evidence of tension . There is otherwise no change from prior radiograph with left basilar atelectasis unchanged . There is stable post cardiac surgery appearance to the cardiomediastinal silhouette .
    OUTPUT:
    
Interval decrease in small left apical pneumothorax with no evidence of tension .