Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: No significant change from the chest radiograph of 1 hr prior with the left pigtail projecting over the left mid lung and small left apical pneumothorax . Left basilar atelectasis has improved . No pleural effusion .
    OUTPUT:
    
No significant change from 1 hr prior . Small left apical pneumothorax .