Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Compared to chest radiograph performed earlier on same day , a left apical pneumothorax is stable to slightly decreased in size . There is no evidence of tension . Overall lung volumes are low , with atelectasis at the left lung base . Scattered areas of perihilar opacity in the right lung are unchanged . Cardiomediastinal silhouette is stable .
    OUTPUT:
    
A left apical pneumothorax is stable to slightly decreased in size . No evidence of tension .